dihydroxyphenylalanine has been researched along with Aging in 86 studies
Dihydroxyphenylalanine: A beta-hydroxylated derivative of phenylalanine. The D-form of dihydroxyphenylalanine has less physiologic activity than the L-form and is commonly used experimentally to determine whether the pharmacological effects of LEVODOPA are stereospecific.
dopa : A hydroxyphenylalanine carrying hydroxy substituents at positions 3 and 4 of the benzene ring.
Aging: The gradual irreversible changes in structure and function of an organism that occur as a result of the passage of time.
| Excerpt | Relevance | Reference |
|---|---|---|
| "Recent positron emission tomography (PET) studies using 3,4-[18F]fluorodihydroxyphenylalanine ([18F]fluorodopa) have reported little or no decrement in dopaminergic function in human striatum (caudate and putamen) during aging." | 7.69 | Striatal 3,4-dihydroxyphenylalanine decarboxylase in aging: disparity between postmortem and positron emission tomography studies? ( Haycock, JW; Hornykiewicz, O; Kish, SJ; Zhong, XH, 1995) |
| "To determine if there is abnormal phenylalanine and biopterin metabolism in patients with dopa-responsive dystonia (DRD), we measured plasma levels of phenylalanine, tyrosine, biopterin, and neopterin at baseline, and 1, 2, 4, and 6 hours after an oral phenylalanine load (100 mg/kg)." | 7.69 | Oral phenylalanine loading in dopa-responsive dystonia: a possible diagnostic test. ( Arnold, LA; Bebin, EM; Fryburg, JS; Gunasekera, RS; Hyland, K; Jacobson, RD; Rost-Ruffner, E; Trugman, JM; Wilson, WG, 1997) |
| "Melatonin has an important role in the aging process as a potential drug to relieve oxidative damage, a likely cause of age-associated brain dysfunction." | 3.76 | Chronic melatonin treatment and its precursor L-tryptophan improve the monoaminergic neurotransmission and related behavior in the aged rat brain. ( Aparicio, S; Barceló, P; Esteban, S; Fiol, MA; Garau, C; Moranta, D; Rial, R, 2010) |
| "We have studied dopamine D2 receptor binding by [11C]raclopride positron emission tomography in 14 patients with dopa-responsive dystonia (DRD)." | 3.70 | D2 receptor binding in dopa-responsive dystonia. ( Antonini, A; Künig, G; Leenders, KL; Meinck, HM; Vontobel, P; Weindl, A, 1998) |
| "Recent positron emission tomography (PET) studies using 3,4-[18F]fluorodihydroxyphenylalanine ([18F]fluorodopa) have reported little or no decrement in dopaminergic function in human striatum (caudate and putamen) during aging." | 3.69 | Striatal 3,4-dihydroxyphenylalanine decarboxylase in aging: disparity between postmortem and positron emission tomography studies? ( Haycock, JW; Hornykiewicz, O; Kish, SJ; Zhong, XH, 1995) |
| "To determine if there is abnormal phenylalanine and biopterin metabolism in patients with dopa-responsive dystonia (DRD), we measured plasma levels of phenylalanine, tyrosine, biopterin, and neopterin at baseline, and 1, 2, 4, and 6 hours after an oral phenylalanine load (100 mg/kg)." | 3.69 | Oral phenylalanine loading in dopa-responsive dystonia: a possible diagnostic test. ( Arnold, LA; Bebin, EM; Fryburg, JS; Gunasekera, RS; Hyland, K; Jacobson, RD; Rost-Ruffner, E; Trugman, JM; Wilson, WG, 1997) |
| "Juvenile spontaneously hypertensive rats (SHR) have higher plasma levels of catechols and markedly larger catechol responses to yohimbine than do normotensive Wistar-Kyoto rats, indicating increased sympathoadrenal outflow and increased alpha 2-adrenergic receptor-mediated restraint of peripheral catecholamine release during hypertension development in SHR." | 3.68 | In vivo hypothalamic release and synthesis of catecholamines in spontaneously hypertensive rats. ( Goldstein, DS; Jakab, G; Kopin, IJ; Lenders, JW; Pacák, K; Yadid, G, 1993) |
| "Patients with Parkinson's disease (PD) have already at the early stages of the disease impaired performance especially in tests measuring frontal lobe functions such as attention." | 2.71 | Cortical 6-[18F]fluoro-L-dopa uptake and frontal cognitive functions in early Parkinson's disease. ( Aalto, S; Bergman, J; Brück, A; Nurmi, E; Rinne, JO, 2005) |
| "The pathological process causing Parkinson's disease may operate closer to the time of presentation than has been suggested." | 1.28 | Striatal function in normal aging: implications for Parkinson's disease. ( Brooks, DJ; Colebatch, JG; Frackowiak, RS; Marsden, CD; Sawle, GV; Shah, A, 1990) |
| "In five children with primary dystonia, the striatal distribution of 18F resembled that seen in the normal older adults." | 1.27 | A rostrocaudal gradient for aromatic acid decarboxylase in the human striatum. ( Chirakal, R; Firnau, G; Garnett, ES; Lang, AE; Nahmias, C, 1987) |
| Timeframe | Studies, this research(%) | All Research% |
|---|---|---|
| pre-1990 | 37 (43.02) | 18.7374 |
| 1990's | 29 (33.72) | 18.2507 |
| 2000's | 12 (13.95) | 29.6817 |
| 2010's | 6 (6.98) | 24.3611 |
| 2020's | 2 (2.33) | 2.80 |
| Authors | Studies |
|---|---|
| Kleppe, R | 1 |
| Waheed, Q | 1 |
| Ruoff, P | 1 |
| Perosa, V | 1 |
| de Boer, L | 1 |
| Ziegler, G | 1 |
| Apostolova, I | 1 |
| Buchert, R | 1 |
| Metzger, C | 1 |
| Amthauer, H | 1 |
| Guitart-Masip, M | 1 |
| Düzel, E | 1 |
| Betts, MJ | 1 |
| Chiaravalloti, A | 1 |
| Barbagallo, G | 1 |
| Ricci, M | 1 |
| Sannino, P | 1 |
| Karalis, G | 1 |
| Ursini, F | 1 |
| Schillaci, O | 1 |
| Burger, IA | 1 |
| Lohmann, C | 1 |
| Messerli, M | 1 |
| Bengs, S | 1 |
| Becker, A | 1 |
| Maredziak, M | 1 |
| Treyer, V | 1 |
| Haider, A | 1 |
| Schwyzer, M | 1 |
| Benz, DC | 1 |
| Kudura, K | 1 |
| Fiechter, M | 1 |
| Giannopoulos, AA | 1 |
| Fuchs, TA | 1 |
| Gräni, C | 1 |
| Pazhenkottil, AP | 1 |
| Gaemperli, O | 1 |
| Buechel, RR | 1 |
| Kaufmann, PA | 1 |
| Gebhard, C | 1 |
| Dreher, JC | 1 |
| Meyer-Lindenberg, A | 1 |
| Kohn, P | 1 |
| Berman, KF | 1 |
| Braskie, MN | 1 |
| Wilcox, CE | 1 |
| Landau, SM | 1 |
| O'Neil, JP | 1 |
| Baker, SL | 1 |
| Madison, CM | 1 |
| Kluth, JT | 1 |
| Jagust, WJ | 1 |
| Esteban, S | 2 |
| Garau, C | 2 |
| Aparicio, S | 2 |
| Moranta, D | 2 |
| Barceló, P | 2 |
| Fiol, MA | 1 |
| Rial, R | 2 |
| Der-Ghazarian, T | 1 |
| Charntikov, S | 1 |
| Varela, FA | 1 |
| Crawford, CA | 2 |
| McDougall, SA | 2 |
| Ramis, M | 1 |
| Tresguerres, JA | 1 |
| Gallagher, CL | 1 |
| Johnson, SC | 1 |
| Bendlin, BB | 1 |
| Chung, MK | 1 |
| Holden, JE | 4 |
| Oakes, TR | 1 |
| Brooks, BR | 1 |
| Konopacki, RA | 1 |
| Dogan, S | 1 |
| Abbs, JH | 1 |
| Xu, G | 1 |
| Nickles, RJ | 3 |
| Pyzalski, RW | 1 |
| Dejesus, OT | 3 |
| Brown, WD | 2 |
| SCHULTE, W | 1 |
| Walter, B | 2 |
| Brust, P | 2 |
| Füchtner, F | 2 |
| Müller, M | 1 |
| Hinz, R | 1 |
| Kuwabara, H | 2 |
| Fritz, H | 1 |
| Zwiener, U | 1 |
| Bauer, R | 2 |
| Vorwieger, G | 1 |
| Stark, H | 1 |
| Herzau, M | 1 |
| Opfermann, T | 1 |
| Steinbach, J | 1 |
| Ganapathy, V | 1 |
| Brück, A | 1 |
| Aalto, S | 1 |
| Nurmi, E | 1 |
| Bergman, J | 1 |
| Rinne, JO | 1 |
| Kumakura, Y | 1 |
| Vernaleken, I | 1 |
| Gründer, G | 1 |
| Bartenstein, P | 1 |
| Gjedde, A | 2 |
| Cumming, P | 2 |
| Porter, JC | 1 |
| Reymond, MJ | 1 |
| Arita, J | 2 |
| Sissom, JF | 1 |
| Kamp, CW | 2 |
| Morgan, WW | 2 |
| Nomura, Y | 2 |
| Oki, K | 1 |
| Demarest, KT | 3 |
| Riegle, GD | 3 |
| Moore, KE | 3 |
| McKay, DW | 1 |
| Coupland, RE | 1 |
| Kent, C | 1 |
| Kent, SE | 1 |
| Hedner, T | 1 |
| Lundborg, P | 1 |
| Dalmaz, Y | 2 |
| Peyrin, L | 2 |
| Armando, I | 1 |
| Nowicki, S | 1 |
| Aguirre, J | 1 |
| Barontini, M | 1 |
| Kish, SJ | 2 |
| Zhong, XH | 1 |
| Hornykiewicz, O | 1 |
| Haycock, JW | 1 |
| Bardo, MT | 1 |
| Esler, MD | 2 |
| Thompson, JM | 2 |
| Kaye, DM | 2 |
| Turner, AG | 2 |
| Jennings, GL | 2 |
| Cox, HS | 2 |
| Lambert, GW | 2 |
| Seals, DR | 2 |
| Kingwell, BA | 1 |
| Morris, M | 1 |
| Cordes, M | 1 |
| Snow, BJ | 2 |
| Cooper, S | 1 |
| Schulzer, M | 1 |
| Pate, BD | 1 |
| Ruth, TJ | 1 |
| Calne, DB | 3 |
| Vingerhoets, FJ | 1 |
| Martin, WR | 2 |
| Rzepecki, LM | 1 |
| Waite, JH | 1 |
| Dean, RT | 1 |
| Gieseg, S | 1 |
| Davies, MJ | 1 |
| Eidelberg, D | 2 |
| Takikawa, S | 1 |
| Dhawan, V | 2 |
| Chaly, T | 2 |
| Robeson, W | 1 |
| Dahl, R | 1 |
| Margouleff, D | 1 |
| Moeller, JR | 1 |
| Patlak, CS | 2 |
| Fahn, S | 1 |
| Pacák, K | 1 |
| Yadid, G | 1 |
| Jakab, G | 1 |
| Lenders, JW | 1 |
| Kopin, IJ | 1 |
| Goldstein, DS | 2 |
| Jensen, EW | 1 |
| Eldrup, E | 2 |
| Kelbaek, H | 1 |
| Nielsen, SL | 1 |
| Christensen, NJ | 2 |
| Morrish, PK | 1 |
| Sawle, GV | 2 |
| Brooks, DJ | 2 |
| Ishikawa, T | 1 |
| Kazumata, K | 1 |
| Mandel, F | 1 |
| Neumeyer, J | 1 |
| Margouleff, C | 1 |
| Babchyck, B | 1 |
| Zanzi, I | 1 |
| Schneider, JS | 1 |
| Hyland, K | 1 |
| Fryburg, JS | 1 |
| Wilson, WG | 1 |
| Bebin, EM | 1 |
| Arnold, LA | 1 |
| Gunasekera, RS | 1 |
| Jacobson, RD | 1 |
| Rost-Ruffner, E | 1 |
| Trugman, JM | 1 |
| Tissingh, G | 1 |
| Bergmans, P | 1 |
| Winogrodzka, A | 1 |
| Stoof, JC | 1 |
| Wolters, EC | 1 |
| Booij, J | 1 |
| Van Royen, EA | 1 |
| Furukawa, Y | 1 |
| Wahl, LM | 1 |
| Nahmias, C | 2 |
| Nappi, AJ | 1 |
| Vass, E | 1 |
| Künig, G | 1 |
| Leenders, KL | 1 |
| Antonini, A | 1 |
| Vontobel, P | 1 |
| Weindl, A | 1 |
| Meinck, HM | 1 |
| Segawa, M | 1 |
| Nishiyama, N | 1 |
| Danielsen, EH | 1 |
| Smith, DF | 1 |
| Gee, AD | 1 |
| Venkatachalam, TK | 1 |
| Hansen, SB | 1 |
| Hermansen, F | 1 |
| Raskind, MA | 1 |
| Peskind, ER | 1 |
| Holmes, C | 1 |
| Nagano, AS | 1 |
| Ito, K | 1 |
| Kato, T | 1 |
| Arahata, Y | 1 |
| Kachi, T | 1 |
| Hatano, K | 1 |
| Kawasumi, Y | 1 |
| Nakamura, A | 1 |
| Yamada, T | 1 |
| Abe, Y | 1 |
| Ishigaki, T | 1 |
| Serebrovskaya, TV | 1 |
| Karaban, IN | 1 |
| Kolesnikova, EE | 1 |
| Mishunina, TM | 1 |
| Swanson, RJ | 1 |
| Beloshitsky, PV | 1 |
| Ilyin, VN | 1 |
| Krasuk, AN | 1 |
| Safronova, OS | 1 |
| Kuzminskaya, LA | 1 |
| Kordower, JH | 1 |
| Emborg, ME | 1 |
| Bloch, J | 1 |
| Ma, SY | 1 |
| Chu, Y | 1 |
| Leventhal, L | 1 |
| McBride, J | 1 |
| Chen, EY | 1 |
| Palfi, S | 1 |
| Roitberg, BZ | 1 |
| Pyzalski, R | 1 |
| Taylor, MD | 1 |
| Carvey, P | 1 |
| Ling, Z | 1 |
| Trono, D | 1 |
| Hantraye, P | 1 |
| Déglon, N | 1 |
| Aebischer, P | 1 |
| Endres, CJ | 1 |
| Shelton, SE | 2 |
| Thobois, S | 1 |
| Guillouet, S | 1 |
| Broussolle, E | 1 |
| Roberts, AD | 1 |
| Muskiet, FA | 1 |
| Fremouw-Ottevangers, DC | 1 |
| van der Meulen, J | 1 |
| Wolthers, BG | 1 |
| de Vries, JA | 1 |
| McNamara, MC | 1 |
| Miller, AT | 1 |
| Benignus, VA | 1 |
| Davis, JN | 1 |
| Clineschmidt, BV | 1 |
| Zacchei, AG | 1 |
| Totaro, JA | 1 |
| Pflueger, AB | 1 |
| McGuffin, JC | 1 |
| Wishousky, TI | 1 |
| Finch, CE | 2 |
| Morgan, DN | 1 |
| McLean, JH | 1 |
| Kostrzewa, RM | 2 |
| Sann, L | 1 |
| Dutruge, J | 1 |
| Da Prada, M | 1 |
| Carlsson, A | 1 |
| Kellogg, C | 1 |
| Hamel, AR | 1 |
| Riklan, M | 2 |
| Huang, HH | 1 |
| Meites, J | 2 |
| Vizuete, ML | 1 |
| Santiago, M | 1 |
| Herrera, AJ | 1 |
| Venero, JL | 1 |
| Machado, A | 1 |
| Cano, J | 1 |
| Tatton, WG | 1 |
| Greenwood, CE | 1 |
| Salo, PT | 1 |
| Seniuk, NA | 1 |
| Hetland, ML | 1 |
| Bratholm, P | 1 |
| Eisen, A | 1 |
| Meneilly, G | 1 |
| Colebatch, JG | 1 |
| Shah, A | 1 |
| Marsden, CD | 1 |
| Frackowiak, RS | 1 |
| Palmer, MR | 1 |
| Kimura, F | 1 |
| Klisans-Fuenmayor, D | 1 |
| Harston, CT | 1 |
| Garnett, ES | 1 |
| Lang, AE | 1 |
| Chirakal, R | 1 |
| Firnau, G | 1 |
| Engel, JA | 1 |
| Rydberg, U | 1 |
| Håkanson, R | 1 |
| Larsson, LI | 1 |
| Sundler, F | 1 |
| Maskin, MB | 1 |
| Chabot, D | 1 |
| Müller-Plettenberg, D | 1 |
| Quadri, SK | 1 |
| Kledzik, GS | 1 |
| Loranger, AW | 1 |
| Goodell, H | 1 |
| McDowell, FH | 1 |
| Lee, JE | 1 |
| Sweet, RD | 1 |
| Paulson, GW | 1 |
| Bellastella, A | 1 |
| Cafaro, MR | 1 |
| Colucci, CF | 1 |
| D'Alessandro, B | 1 |
| Gasbarro, R | 1 |
| Singer, E | 1 |
| Ignarro, LJ | 1 |
| Shideman, FE | 1 |
| Trial | Phase | Enrollment | Study Type | Start Date | Status | ||
|---|---|---|---|---|---|---|---|
| Prazosin for Disruptive Agitation in Alzheimer's Disease (AD) (PEACE-AD)[NCT03710642] | Phase 2 | 35 participants (Actual) | Interventional | 2018-10-23 | Completed | ||
| [information is prepared from clinicaltrials.gov, extracted Sep-2024] | |||||||
"The ADCS-ADL-Severe questionnaire is a secondary outcome measure aimed at detecting functional decline in people with severe AD. This scale is best suited for evaluating people with MMSE scores below 15/30, or equivalent. Questions are administered to a qualified caregiver informant about a set of 19 basic and instrumental ADL. Instrumental ADL are selected to be relevant to this level of severity of dementia, e.g., obtaining a beverage, turning lights on and off, turning a faucet on and off. Performance of each of these activities during the past 4 weeks, as well as the level of performance, are rated. A total score is derived by summing scores across items, and ranges from 0 (maximal impairment) to 54 (maximally independent function).~This outcome is the change from baseline to week 12." (NCT03710642)
Timeframe: 12 weeks
| Intervention | score on a scale (Least Squares Mean) |
|---|---|
| Treatment (Prazosin) | -1.47055 |
| Placebo Oral Capsule | -4.53993 |
"The ADCS-CGIC-A is the primary outcome measure. It will be anchored to disruptive agitation, the target behaviors in this study. It measures whether the effects of active treatment are substantial enough to be detected by a skilled and experienced clinician on the basis of a direct examination of the participant and an interview of the participant's primary caregiver and other LTC facility staff. The baseline assessment is qualitative therefore there is no score at baseline; post-baseline scores represent a change score compared to baseline.~The ADCS-CGIC-A is a 7-point scale that is structured as the clinician's assessment of change from baseline compared to the ADCS-CGIC-A Baseline Worksheet. There is no baseline score; post-baseline scores range from 1 (improvement) to 7 (worsening). A score of 1-2 indicates clinically meaningful improvement; a score of 3-5 indicates no clinically meaningful change; a score of 6-7 indicates clinically meaningful worsening." (NCT03710642)
Timeframe: From Baseline through Week 12.
| Intervention | score on a scale (Least Squares Mean) |
|---|---|
| Treatment (Prazosin) | 3.434 |
| Placebo Oral Capsule | 3.442 |
"Comparison of effects on caregiver distress/occupational disruptiveness scores on the NPI/NPI-NH. Minimum score is 0 and maximum score is 60. A higher score is a worse outcome.~This outcome is the change from baseline to week 12." (NCT03710642)
Timeframe: 12 weeks
| Intervention | score on a scale (Least Squares Mean) |
|---|---|
| Treatment (Prazosin) | -2.4438 |
| Placebo Oral Capsule | 0.9446 |
"The NPI was designed to characterize the neuropsychiatric symptoms and psychopathology of patients with AD and other dementias residing in the community about which information was obtained from family caregivers. The content of the questions and their scoring in the NPI-NH are identical to those of the NPI except for some slight rephrasing to be consistent with the LTC environment where information is gathered from professional caregivers. Assessment of the impact of behavioral disturbances on family and professional caregivers, is assessed by a caregiver distress scale in the NPI and an occupational disruptiveness scale in the NPI-NH; scoring of this component remains identical. Minimum score is 0 and highest score is 144. A higher score means a worse outcome.~This outcome is the change from baseline to week 12." (NCT03710642)
Timeframe: 12 weeks
| Intervention | units on a scale (Least Squares Mean) |
|---|---|
| Treatment (Prazosin) | -6.033 |
| Placebo Oral Capsule | 5.506 |
Cumulative total dose of Lorazepam rescue medication administered during the trial. Information on the total mg rescue lorazepam administered will be collected as additional secondary outcome measures. If prazosin is more effective than placebo, it is predicted that participants randomized to prazosin will be prescribed lower cumulative mg of rescue lorazepam for management of persistent or worsening disruptive agitation. (NCT03710642)
Timeframe: 12 weeks
| Intervention | mg (Mean) |
|---|---|
| Treatment (Prazosin) | 0.25 |
| Placebo Oral Capsule | 0.14 |
Comparison of proportions of responders versus non responders on the ADCS-CGIC-A. Responders are defined as those with moderate or marked improvement in agitation symptoms compared to baseline assessment. (NCT03710642)
Timeframe: 12 weeks
| Intervention | Participants (Count of Participants) |
|---|---|
| Treatment (Prazosin) | 7 |
| Placebo Oral Capsule | 1 |
Cox proportional hazard modelling comparing the median time to drop out between treatment groups. (NCT03710642)
Timeframe: 12 weeks
| Intervention | days (Median) |
|---|---|
| Treatment (Prazosin) | 65.63 |
| Placebo Oral Capsule | 54.62 |
5 reviews available for dihydroxyphenylalanine and Aging
| Article | Year |
|---|---|
Secretion of hypothalamic dopamine into the hypophysial portal vasculature: an overview.
Topics: Aging; Animals; Catecholamines; Dihydroxyphenylalanine; Dopamine; Hypothalamic Hormones; Hypothalamo | 1983 |
Reactive species and their accumulation on radical-damaged proteins.
Topics: Aging; Animals; Biomarkers; Dihydroxyphenylalanine; Free Radicals; Humans; Hydrogen Peroxide; Reacti | 1993 |
DOPA-responsive dystonic parkinsonism--pathophysiologic considerations.
Topics: Aging; Basal Ganglia; Base Sequence; Dihydroxyphenylalanine; Dystonia; GTP Cyclohydrolase; Humans; M | 1999 |
Contributions of PET and SPECT to the understanding of the pathophysiology of Parkinson's disease.
Topics: Aging; Animals; Antiparkinson Agents; Basal Ganglia; Brain Tissue Transplantation; Cell Transplantat | 2001 |
Age-related changes in brain catecholamines: a synopsis of findings in C57BL/6J mice and other rodent models.
Topics: Adenylyl Cyclases; Aging; Animals; Biological Clocks; Brain; Catecholamines; Dihydroxyphenylalanine; | 1978 |
5 trials available for dihydroxyphenylalanine and Aging
| Article | Year |
|---|---|
Cortical 6-[18F]fluoro-L-dopa uptake and frontal cognitive functions in early Parkinson's disease.
Topics: Aging; Cerebral Cortex; Cognition Disorders; Dihydroxyphenylalanine; Female; Humans; Male; Middle Ag | 2005 |
Aging effects on human sympathetic neuronal function.
Topics: Adult; Aged; Aging; Dihydroxyphenylalanine; Heart; Heart Rate; Humans; Kidney; Male; Methoxyhydroxyp | 1995 |
The rate of progression of Parkinson's disease. A longitudinal [18F]DOPA PET study.
Topics: Aged; Aging; Caudate Nucleus; Dihydroxyphenylalanine; Disease Progression; Humans; Longitudinal Stud | 1996 |
Influence of development and aging on brain biopterin: implications for dopa-responsive dystonia onset.
Topics: Adolescent; Adult; Aged; Aged, 80 and over; Aging; Biopterins; Child; Child, Preschool; Dihydroxyphe | 1998 |
Geriatric men at altitude: hypoxic ventilatory sensitivity and blood dopamine changes.
Topics: Adaptation, Physiological; Adult; Age Factors; Aging; Altitude; Analysis of Variance; Dihydroxypheny | 2000 |
76 other studies available for dihydroxyphenylalanine and Aging
| Article | Year |
|---|---|
DOPA Homeostasis by Dopamine: A Control-Theoretic View.
Topics: Aging; Dihydroxyphenylalanine; Dopamine; Homeostasis; Humans; Levodopa; Models, Neurological; Oxidat | 2021 |
The Role of the Striatum in Learning to Orthogonalize Action and Valence: A Combined PET and 7 T MRI Aging Study.
Topics: Adult; Aged; Aging; Caudate Nucleus; Conditioning, Operant; Dihydroxyphenylalanine; Dopamine; Female | 2020 |
Ageing effect on 18F-DOPA and 123I-MIBG uptake: a cross-sectional study.
Topics: 3-Iodobenzylguanidine; Adult; Aged; Aged, 80 and over; Aging; Biological Transport; Cross-Sectional | 2018 |
Age- and sex-dependent changes in sympathetic activity of the left ventricular apex assessed by 18F-DOPA PET imaging.
Topics: Adolescent; Adult; Aged; Aged, 80 and over; Aging; Child; Child, Preschool; Dihydroxyphenylalanine; | 2018 |
Age-related changes in midbrain dopaminergic regulation of the human reward system.
Topics: Adult; Age Factors; Aged; Aging; Dihydroxyphenylalanine; Dopamine; Female; Humans; Magnetic Resonanc | 2008 |
Relationship of striatal dopamine synthesis capacity to age and cognition.
Topics: Adult; Aged; Aged, 80 and over; Aging; Aromatic-L-Amino-Acid Decarboxylases; Cognition; Corpus Stria | 2008 |
Chronic melatonin treatment and its precursor L-tryptophan improve the monoaminergic neurotransmission and related behavior in the aged rat brain.
Topics: Aging; Animals; Antioxidants; Behavior, Animal; Brain; Corpus Striatum; Dihydroxyphenylalanine; Dopa | 2010 |
Effects of repeated and acute aripiprazole or haloperidol treatment on dopamine synthesis in the dorsal striatum of young rats: comparison to adult rats.
Topics: Aging; Animals; Animals, Newborn; Antipsychotic Agents; Aripiprazole; Autoreceptors; Brain Chemistry | 2010 |
Improving effects of long-term growth hormone treatment on monoaminergic neurotransmission and related behavioral tests in aged rats.
Topics: 5-Hydroxytryptophan; Aging; Animals; Aromatic Amino Acid Decarboxylase Inhibitors; Aromatic-L-Amino- | 2010 |
A longitudinal study of motor performance and striatal [18F]fluorodopa uptake in Parkinson's disease.
Topics: Aged; Aging; Antiparkinson Agents; Carbidopa; Caudate Nucleus; Corpus Striatum; Dihydroxyphenylalani | 2011 |
[PSYCHIATRIC UNIVERSITY CLINIC AND PSYCHIATRIC STATE HOSPITAL].
Topics: Aging; Brain Diseases; Dihydroxyphenylalanine; Germany; Germany, West; Hospitals, Psychiatric; Hospi | 1964 |
Age-dependent effects of severe traumatic brain injury on cerebral dopaminergic activity in newborn and juvenile pigs.
Topics: Age Factors; Aging; Animals; Animals, Newborn; Aromatic-L-Amino-Acid Decarboxylases; Brain Injuries; | 2004 |
The influx of neutral amino acids into the porcine brain during development: a positron emission tomography study.
Topics: Aging; Amino Acids, Neutral; Animals; Animals, Newborn; Blood-Brain Barrier; Brain; Brain Chemistry; | 2004 |
PET studies of net blood-brain clearance of FDOPA to human brain: age-dependent decline of [18F]fluorodopamine storage capacity.
Topics: Adult; Aging; Brain; Diffusion; Dihydroxyphenylalanine; Fluorine Radioisotopes; Humans; Middle Aged; | 2005 |
Ontogeny of mechanisms which regulate light/dark differences in retinal dopamine synthesis.
Topics: Adaptation, Physiological; Aging; Animals; Bicuculline; Darkness; Dihydroxyphenylalanine; Dopamine; | 1984 |
TRH-induced behavioral arousal in developing rats pretreated with 6-hydroxydopa.
Topics: Aging; Animals; Animals, Newborn; Catecholamines; Dihydroxyphenylalanine; Drug Interactions; Female; | 1980 |
Characteristics of dopaminergic neurons in the aged male rat.
Topics: Aging; Animals; Dihydroxyphenylalanine; Dopamine; Hydroxydopamines; Luteinizing Hormone; Male; Neuro | 1980 |
Sexual differences in tuberoinfundibular dopamine nerve activity induced by neonatal androgen exposure.
Topics: Aging; Animals; Animals, Newborn; Benzyl Alcohols; Castration; Dihydroxyphenylalanine; Dopamine; Fem | 1981 |
Normal function of extra-adrenal chromaffin tissues in the young rabbit and guinea-pig.
Topics: Adrenal Cortex; Adrenal Glands; Adrenal Medulla; Aging; Animals; Animals, Newborn; Catecholamines; C | 1982 |
Postnatal development of the light response of the dopaminergic neurons in the rat retina.
Topics: Aging; Animals; Aromatic Amino Acid Decarboxylase Inhibitors; Dark Adaptation; Dihydroxyphenylalanin | 1982 |
Effect of gammahydroxybutyric acid on catecholamine synthesis and utilization in the developing rat brain.
Topics: Aging; Animals; Brain; Dihydroxyphenylalanine; Dopamine; Female; Hydroxybutyrates; Motor Activity; N | 1982 |
Sex-differences in catecholamine metabolites in human urine during development and at adulthood.
Topics: Adolescent; Adult; Aging; Catecholamines; Child; Child, Preschool; Dihydroxyphenylalanine; Female; H | 1982 |
A decreased tubular uptake of dopa results in defective renal dopamine production in aged rats.
Topics: 3,4-Dihydroxyphenylacetic Acid; Aging; Animals; Aromatic-L-Amino-Acid Decarboxylases; Biological Tra | 1995 |
Striatal 3,4-dihydroxyphenylalanine decarboxylase in aging: disparity between postmortem and positron emission tomography studies?
Topics: Adolescent; Adult; Aged; Aged, 80 and over; Aging; Corpus Striatum; Dihydroxyphenylalanine; Dopa Dec | 1995 |
Effects of EEDQ on the synthesis and metabolism of dopamine in preweanling and adult rats.
Topics: 3,4-Dihydroxyphenylacetic Acid; Aging; Animals; Animals, Suckling; Dihydroxyphenylalanine; Dopamine; | 1994 |
Effects of aging on the responsiveness of the human cardiac sympathetic nerves to stressors.
Topics: Adult; Aged; Aging; Blood Pressure; Dihydroxyphenylalanine; Exercise; Heart; Heart Rate; Humans; Mal | 1995 |
Age-dependent decline of nigrostriatal dopaminergic function: a positron emission tomographic study of grandparents and their grandchildren.
Topics: Adult; Aged; Aging; Corpus Striatum; Dihydroxyphenylalanine; Dopamine; Family; Female; Humans; Male; | 1994 |
An aging effect in striatal fluorodopa uptake? Large versus small ROIs.
Topics: Aging; Corpus Striatum; Dihydroxyphenylalanine; Humans | 1994 |
The byssus of the zebra mussel, Dreissena polymorpha. I: Morphology and in situ protein processing during maturation.
Topics: Aging; Amino Acids; Animals; Bivalvia; Carbohydrates; Cell Adhesion Molecules; Dihydroxyphenylalanin | 1993 |
Striatal 18F-dopa uptake: absence of an aging effect.
Topics: Adult; Aged; Aging; Corpus Striatum; Dihydroxyphenylalanine; Female; Fluorine Radioisotopes; Humans; | 1993 |
In vivo hypothalamic release and synthesis of catecholamines in spontaneously hypertensive rats.
Topics: Aging; Animals; Brain; Catecholamines; Catechols; Dialysis; Dihydroxyphenylalanine; Hydrazines; Hype | 1993 |
Venous plasma noradrenaline increases with age: correlation to total blood volume and long-term smoking habits.
Topics: 3,4-Dihydroxyphenylacetic Acid; Adult; Aged; Aged, 80 and over; Aging; Benserazide; Blood Volume; Bo | 1993 |
Comparative nigrostriatal dopaminergic imaging with iodine-123-beta CIT-FP/SPECT and fluorine-18-FDOPA/PET.
Topics: Adult; Aged; Aging; Carrier Proteins; Cocaine; Corpus Striatum; Dihydroxyphenylalanine; Dopamine; Do | 1996 |
Preservation of autoreceptor-mediated increases in dopamine synthesis in aged mice with experimentally-induced parkinsonism.
Topics: 1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine; 3,4-Dihydroxyphenylacetic Acid; Aging; Animals; Aromat | 1997 |
Oral phenylalanine loading in dopa-responsive dystonia: a possible diagnostic test.
Topics: Administration, Oral; Adolescent; Adult; Aged; Aged, 80 and over; Aging; Biopterins; Child, Preschoo | 1997 |
Nigrostriatal dopaminergic imaging with iodine-123-beta CIT-FP/SPECT and fluorine-18-FDOPA/PET.
Topics: Aging; Carrier Proteins; Cocaine; Corpus Striatum; Dihydroxyphenylalanine; Dopamine; Dopamine Plasma | 1997 |
Statistical power analysis for PET studies in humans.
Topics: Age Factors; Aging; Brain; Dihydroxyphenylalanine; Fluorine Radioisotopes; Humans; Research Design; | 1998 |
Hydroxyl radical formation via iron-mediated Fenton chemistry is inhibited by methylated catechols.
Topics: Aging; Brain; Catechol O-Methyltransferase; Catecholamines; Catechols; Chromatography, High Pressure | 1998 |
D2 receptor binding in dopa-responsive dystonia.
Topics: Adolescent; Adult; Age of Onset; Aging; Carbon Radioisotopes; Caudate Nucleus; Dihydroxyphenylalanin | 1998 |
Cerebral 6-[(18)F]fluoro-L-DOPA (FDOPA) metabolism in pig studied by positron emission tomography.
Topics: Aging; Animals; Animals, Newborn; Aromatic Amino Acid Decarboxylase Inhibitors; Blood-Brain Barrier; | 1999 |
Patterns of cerebrospinal fluid catechols support increased central noradrenergic responsiveness in aging and Alzheimer's disease.
Topics: Adrenergic alpha-Agonists; Adrenergic alpha-Antagonists; Aged; Aging; Alzheimer Disease; Antimetabol | 1999 |
Extrastriatal mean regional uptake of fluorine-18-FDOPA in the normal aged brain--an approach using MRI-aided spatial normalization.
Topics: Aged; Aging; Brain; Dihydroxyphenylalanine; Female; Fluorine Radioisotopes; Humans; Magnetic Resonan | 2000 |
Neurodegeneration prevented by lentiviral vector delivery of GDNF in primate models of Parkinson's disease.
Topics: 1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine; Aging; Animals; Antigens, CD; Dihydroxyphenylalanine; | 2000 |
Noninvasive assessment of aromatic L-amino acid decarboxylase activity in aging rhesus monkey brain in vivo.
Topics: Aging; Animals; Aromatic-L-Amino-Acid Decarboxylases; Brain; Dihydroxyphenylalanine; Macaca mulatta; | 2001 |
Effect of tetrabenazine on the striatal uptake of exogenous L-DOPA in vivo: a PET study in young and aged rhesus monkeys.
Topics: Adrenergic Uptake Inhibitors; Aging; Animals; Aromatic-L-Amino-Acid Decarboxylases; Dihydroxyphenyla | 2002 |
Determination of some L-3,4-dihydroxyphenylalanine and dopamine metabolites in urine by means of mass fragmentography.
Topics: 3-Methoxy-4-hydroxyphenylethanol; 3,4-Dihydroxyphenylacetic Acid; Adult; Aging; Child; Child, Presch | 1978 |
Age related changes in the effect of electroconvulsive shock (ECS) on the in vivo hydroxylation of tyrosine and tryptophan in rat brain.
Topics: 5-Hydroxytryptophan; Aging; Animals; Aromatic Amino Acid Decarboxylase Inhibitors; Benzyl Alcohols; | 1977 |
Fenfluramine and brain serotonin.
Topics: 5-Hydroxytryptophan; Aging; Animals; Animals, Newborn; Brain; Dealkylation; Dihydroxyphenylalanine; | 1978 |
Effects of 6-hydroxydopamine and 6-hydroxydopa on development of behavior.
Topics: Aging; Animals; Animals, Newborn; Behavior, Animal; Brain Chemistry; Dihydroxyphenylalanine; Explora | 1979 |
Age-related changes in catecholamine metabolites of human urine from birth to adulthood.
Topics: 3,4-Dihydroxyphenylacetic Acid; Adolescent; Adult; Aging; Catecholamines; Child; Child, Preschool; D | 1979 |
Dopamine content and synthesis in retina and n. accumbens septi: pharmacological and light-induced modifications.
Topics: 2H-Benzo(a)quinolizin-2-ol, 2-Ethyl-1,3,4,6,7,11b-hexahydro-3-isobutyl-9,10-dimethoxy-; Adaptation, | 1977 |
Age-dependent changes in central dopaminergic and other monoaminergic systems.
Topics: Aging; Animals; Avoidance Learning; Biogenic Amines; Castration; Child; Dihydroxyphenylalanine; Dopa | 1978 |
Audiogenic seizures: relation to age and mechanisms of monoamine neurotransmission.
Topics: 5-Hydroxytryptophan; Acoustic Stimulation; Aging; Animals; Benserazide; Brain; Catecholamines; Dihyd | 1976 |
Cognitive and perceptual effects of long-range L-dopa therapy in Parkinsonism.
Topics: Age Factors; Aged; Aging; Attention; Bender-Gestalt Test; Cognition; Dihydroxyphenylalanine; Female; | 1975 |
Reproductive capacity of aging female rats.
Topics: Aging; Animals; Dihydroxyphenylalanine; Estrus; Female; Organ Size; Ovary; Pituitary Gland; Pregnanc | 1975 |
Effects of neonatal bilateral eye enucleation on postnatal development of the monoamines in posterior thalamus of the rat.
Topics: 5-Hydroxytryptophan; Aging; Animals; Animals, Newborn; Aromatic Amino Acid Decarboxylase Inhibitors; | 1991 |
Transmitter synthesis increases in substantia nigra neurons of the aged mouse.
Topics: 3,4-Dihydroxyphenylacetic Acid; Aging; Animals; Axonal Transport; Corpus Striatum; Dihydroxyphenylal | 1991 |
The relationship between age and venous plasma concentrations of noradrenaline, catecholamine metabolites, DOPA and neuropeptide Y-like immunoreactivity in normal human subjects.
Topics: 3,4-Dihydroxyphenylacetic Acid; Adult; Aged; Aged, 80 and over; Aging; Blood Pressure; Catecholamine | 1991 |
Normal aging of the nervous system.
Topics: Aging; Deoxyglucose; Dihydroxyphenylalanine; Fluorodeoxyglucose F18; Humans; Intelligence Tests; Ner | 1991 |
Striatal function in normal aging: implications for Parkinson's disease.
Topics: Adult; Aged; Aging; Caudate Nucleus; Corpus Striatum; Dihydroxyphenylalanine; Female; Fluorine Radio | 1990 |
Nigrostriatal function in humans studied with positron emission tomography.
Topics: Adult; Aged; Aged, 80 and over; Aging; Corpus Striatum; Dihydroxyphenylalanine; Female; Humans; Male | 1989 |
Effect of aging on in vitro dopamine biosynthesis in the median eminence of rat hypothalamic slices.
Topics: Aging; Animals; Calcium; Cyclic AMP; Dihydroxyphenylalanine; Dopamine; Female; In Vitro Techniques; | 1986 |
Alterations in noradrenergic innervation of the brain following dorsal bundle lesions in neonatal rats.
Topics: Aging; Animals; Animals, Newborn; Brain Chemistry; Cerebellum; Dihydroxyphenylalanine; Locus Coerule | 1986 |
Restraint stress decreases the neurosecretory activity of tuberoinfundibular dopaminergic neurons in young but not in aged female rats.
Topics: Aging; Animals; Dihydroxyphenylalanine; Dopamine; Estrus; Female; Hypothalamo-Hypophyseal System; Me | 1987 |
A rostrocaudal gradient for aromatic acid decarboxylase in the human striatum.
Topics: Adolescent; Adult; Aging; Aromatic-L-Amino-Acid Decarboxylases; Child; Corpus Striatum; Dihydroxyphe | 1987 |
Age-dependent effects of ethanol on central monoamine synthesis in the male rat.
Topics: 5-Hydroxytryptophan; Aging; Animals; Biogenic Amines; Brain; Dihydroxyphenylalanine; Ethanol; Male; | 1985 |
Peptide and amine producing endocrine-like cells in the chicken thymus. A chemical, histochemical and electron microscopic study.
Topics: Aging; Animals; Chickens; Dihydroxyphenylalanine; Dopamine; Female; Histocytochemistry; Male; Micros | 1974 |
Effects of "short-term" versus "long-term" L-Dopa therapy in parkinsonism on critical flicker frequency.
Topics: Aging; Arousal; Brain Chemistry; Dihydroxyphenylalanine; Dopamine; Flicker Fusion; Humans; Parkinson | 1974 |
Catecholamine metabolism in the brains of ageing male mice.
Topics: Aging; Animals; Brain; Brain Stem; Cerebellum; Corpus Striatum; Dihydroxyphenylalanine; DNA; Dopa De | 1973 |
[Notes from the Annual Congress 1972 of the German Society of Gerontology].
Topics: Aged; Aging; Arteriosclerosis; Congresses as Topic; Connective Tissue; Depression; Dihydroxyphenylal | 1973 |
Reinitiation of estrous cycles in old constant-estrous rats by central-acting drugs.
Topics: Aging; Animals; Dihydroxyphenylalanine; Epinephrine; Estrus; Female; Follicle Stimulating Hormone; H | 1973 |
Parkinsonism, L-dopa, and intelligence.
Topics: Age Factors; Aged; Aging; Dihydroxyphenylalanine; Humans; Intelligence; Intelligence Tests; Parkinso | 1973 |
Failures of L-dopa.
Topics: Aged; Aging; Depression; Dihydroxyphenylalanine; Humans; Male; Medication Errors; Middle Aged; Movem | 1973 |
[Behavior of plasmatic HGH after stimulation with L-Dopa in normal elderly subjects and in subjects with cerebrovascular disorders: preliminary study].
Topics: Adult; Age Factors; Aged; Aging; Cerebrovascular Disorders; Dihydroxyphenylalanine; Growth Hormone; | 1973 |
Premature social aging: the social-psychological consequences of a chronic illness.
Topics: Aging; Anger; Attitude; Attitude to Health; Boredom; Chronic Disease; Dihydroxyphenylalanine; Emotio | 1974 |
Appearance and concentrations of catecholamines and their biosynthesis in the embryonic and developing chick.
Topics: Aging; Animals; Catecholamines; Chick Embryo; Chickens; Chromatography, Ion Exchange; Dihydroxypheny | 1968 |