piperidines and Adenoma

In a multi-center trial, the feasibility of combining remifentanil (RF) and target-controlled infusion of propofol (P) for patients undergoing transsphenoidal resection of the pituitary gland was tested. After IRB approval, 74 patients (29 male/45 female) were included in the study. The concentration of RF and the target concentration of P were recorded as were heart rate (HR) and mean arterial blood pressure (MAP). For intubation the RF dosage was 0.26 +/- 0.06 microgram.kg-1.min-1 and the target concentration of P was 3.16 +/- 0.63 micrograms.ml-1. After induction, HR and MAP decreased significantly. The painful events of the operation were preparation of the nasal mucous membrane and penetration of the sella turcica. By adjusting the RF dose to 0.31 +/- 0.09 microgram.kg-1. min-1 and the target concentration of P to 3.48 +/- 1.49 micrograms.ml-1, an increase of HR and MAP above initial values was avoided at this time. Hypotension and bardycardia were treated in eight patients (10.8%) with a vasopressor, in four patients (5.4%) with atropine and in four more patients (5.4%) with a combination of these drugs. Two patients (2.7%) needed antihypertensive therapy. The average time interval between the end of P-TCI and spontaneous breathing was 6 +/- 3 min (median 6 min) and till patients opened their eyes 9 +/- 4 min (median 9 min). After 13 +/- 4 min (median 13 min) the patients became orientated. The average doses of analgetics were 19.5 +/- 19.9 mg piritramide and 1.8 +/- 1.0 g metamizol during the first 12 hours postoperatively. Eight patients (10.8%) did not need any analgetics. We suggest that the combination of RF and P as a "fast track concept" can supplement the repertoire of anaesthetic managements used for transsphenoidal resection of the pituitary gland.

Topics: Adenoma; Adult; Anesthesia Recovery Period; Anesthesia, General; Anesthetics, Intravenous; Blood Pressure; Feasibility Studies; Female; Heart Rate; Humans; Hypophysectomy; Male; Middle Aged; Pain Measurement; Piperidines; Pituitary Neoplasms; Propofol; Remifentanil; Sphenoid Sinus

The availability of a new specific anti 5HT-2 compound, ritanserin (RTS), led us to further investigate the role of serotonin in controlling PRL secretion. The drug was administered to normoprolactinaemic subjects and to patients with differing hyperprolactinaemic conditions. While RTS failed to modify PRL levels in normoprolactinaemic subjects and in patients with PRL-secreting pituitary adenomas, a marked decrease in the hormone was obtained in patients with functional and puerperal hyperprolactinaemia. The lack of effect of RTS in PRL-secreting pituitary adenomas suggests that the reported suppression of PRL by other antiserotoninergic drugs, such as metergoline, is probably due to their concomitant dopaminergic activity.

Topics: Adenoma; Female; Follicular Phase; Humans; Hyperprolactinemia; Piperidines; Pituitary Neoplasms; Postpartum Period; Pregnancy; Prolactin; Ritanserin; Serotonin Antagonists; Single-Blind Method; Sulpiride

Tofacitinib is an oral Janus kinase (JAK) inhibitor for the treatment of rheumatoid arthritis. Tofacitinib preferentially inhibits receptor signaling through JAK3 and JAK1, relative to JAK2. In the 2-year rat carcinogenicity study, there were tofacitinib, dose-related increases in the incidences of testicular Leydig cell hyperplasia and benign adenomas in male rats, and decreased incidences of mammary tumors and duct dilatation/galactocele in female rats. Such findings in rats are typical of agents, such as dopamine agonists, which decrease prolactin (PRL) activity. Since prolactin signals through the JAK2 pathway, we hypothesized that these findings were off-target effects due to inhibition of PRL signaling via JAK2. The studies reported here were designed to investigate the interruption of PRL signaling pathways in Leydig cells. In isolated primary rat Leydig cells, PRL increased phosphorylated Signal Transducer and Activator of Transcription-5 protein, and mRNA levels for luteinizing hormone receptor. Tofacitinib, at concentrations observed in the rat carcinogenicity study, dose-dependently inhibited these effects. These observations illustrate a novel mechanism, the inhibition of prolactin signaling by which modulation of JAK activity can modulate PRL signaling pathways to induce Leydig cell tumors in rats. Since human Leydig cells lack this PRL dependence for normal function, these rodent tumors do not indicate a health risk to human patients.

Topics: Adenoma; Animals; Hyperplasia; Leydig Cells; Male; Piperidines; Prolactin; Protein Kinase Inhibitors; Pyrimidines; Pyrroles; Rats; Signal Transduction; Testis

Combination of local and regional anesthetic agents are widely used in emergency and surgical setting and the interaction between the medications used in general anesthesia and these local and/or regional anesthetic becomes a growing concern in current patient management system. The interaction between general anesthetic agents and the local anesthetic agents given epidurally, spinally, intravenously or intramuscularly and the effects of BIS monitorisation on combined propofol-remifentanil anesthesia are examined in several studies. In literature, there is no research investigating the effect of lidocaine infusion on remifentanil and anesthetic dosage used in hypotensive anesthesia. The aim of this study is to examine this effect.. We studied 39, ASA I-II patients undergoing elective transsphenoidal endoscopic hypophyseal adenoma excision procedure. After preoperative examination and informed consent of the patient, monitorisation with non invasive blood pressure measurement, electrocardiography, pulse oxymeter and Bispectral Index (BIS) was performed. 0.9% NaCl infusion was started via a 20 G route. Lidocaine (1%) was given as 1.5 mg.kg(-1) hour-1 infusion after 1.5 mg.kg(-1) bolus dosage given in 10 minutes. Lidocaine infusion was started at the same time with anesthesia induction and was stopped after surgery. 0.9% NaCl was given as bolus dosage and as infusion in control group. Induction was maintained via propofol (1%) with 10 mg (1 ml) doses given in 5 seconds and it was applied in every 15 seconds until BIS < 45'. During maintenance of anesthesia desflurane-remifentanil-oxygen (50%)-air (50%) mixture was used. Desflurane was titrated by BIS measurement between 40 and 5012. Remifentanil infusion was started after propofol induction with 0.1 µg.kg(-1).min(-1) dosage and it was titrated between 0.1-0.5 µg.kg(-1).min(-1) levels. For intubation, rocuronium with 0.8 mg kg(-1) dosage was given during induction. After the surgical procedure, it was antagonised with neostigmine and atropine. For postoperative analgesia 1 g paracetamole was given IV after the surgery within 15 minutes and it was reapplied with 1 gr doses in every 6 hours. After extubation, the pain of the patients was examined at 15. minute at the recovery room with VRS (VRS; 0-no pain, 1-slight pain, 2-moderate pain, 3-severe pain). If VRS was greater than 2, 50 mg dolantine was given IM. For prevention of nausea and vomitting, 8 mg ondansetron was given IV. Perioperative total doses of remifentanil, desflurane (ml) (anesthesia machine records) and lidocaine (mg) were recorded after the surgery. Perioperative hemodynamic parameters (systolic, diastolic, mean blood pressures, heart rates) were recorded after monitorisation (basal), after intubation, after the start of the surgery and after extubation.. There were no statistically significant difference between two groups with respect to patient characteristics (age, gender, weight, length, Basal Mass Index = BMI) (p > 0.05). The duration of anesthesia and surgery were also not different statistically (p > 0.05). There were no statistically significant difference between two groups with respect to remifentanil dose (p > 0.05). There were no statistically significant difference between two groups with respect to eye opening and extubation times (p > 0.05). When usage rates and amounts of dolantine, paracetamole and novalgine were compared, we found no statistically significant difference between two groups (p > 0.05). Basal mean arterial blood pressure measurements of the patients and mean arterial blood pressure measurements of the patients after induction, after intubation, 1 minute, 5 minutes, 10 minutes, 15 minutes after discharge of surgery and after extubation showed no statistically significant difference (p > 0.05). Basal heart rate measurements and the heart rates after induction, after intubation, 1 minute, 5 minutes, 10 minutes, 15 minutes after discharge of surgery and after extubation showed no statistically significant difference (p > 0.05). Basal BIS measurements and BIS measurements after induction, after intubation, 1 minute, 5 minutes, 10 minutes, 15 minutes after discharge of surgery and after extubation showed no statistically significant difference (p > 0.05).. We found no statistically significant difference between two groups about different parameters. But new investigations with different local anesthetic agents may show sigificant difference and usage of these local anesthetic agents may be advised.

Topics: Adenoma; Adolescent; Adult; Aged; Anesthetics, Combined; Anesthetics, Intravenous; Anesthetics, Local; Blood Pressure; Blood Pressure Monitors; Consciousness Monitors; Drug Administration Schedule; Electrocardiography; Endoscopy; Female; Heart Rate; Humans; Hypotension; Infusions, Parenteral; Intraoperative Neurophysiological Monitoring; Lidocaine; Male; Middle Aged; Operative Time; Oximetry; Pain, Postoperative; Piperidines; Pituitary Neoplasms; Predictive Value of Tests; Remifentanil; Time Factors; Treatment Outcome; Young Adult

The Apc(MIN/+) mouse is a well-characterised model of intestinal tumourigenesis in which animals develop macroscopically detectable adenomas. However, most of the adenomas are formed in the small intestine and resolution of events in the colon, the most relevant site for human disease, is limited. Inducing colitis with dextran sodium sulphate (DSS) can selectively enhance the development of lesions in the colon. We demonstrated that a DSS pre-treatment is well tolerated and effective at inducing colon adenomas in an Apc(MIN/+) mouse model. We then investigated the effect of inhibiting vascular endothelial growth factor (VEGFR)- and epidermal growth factor receptor (EGFR)-dependent signalling pathways on the development of adenomas induced in DSS-pretreated (DSS/Apc(MIN/+)) or non-DSS-pretreated (Apc(MIN/+)) mice using vandetanib (ZD6474), a potent and selective inhibitor of VEGFR and EGFR tyrosine kinase activity. Eight-week old Apc(MIN/+) mice were given either drinking water or 1.8% DSS and then vandetanib (ZD6474) (50 mg/kg/day) or vehicle by oral gavage for 28 days and sacrificed 24 h after the last dose and assessed for adenoma formation in the intestines. DSS pre-treatment was well tolerated and significantly enhanced formation of adenomas in the colon of control Apc(MIN/+) mice. Vandetanib treatment significantly reduced adenoma formation in the small intestine by 68% (P=0.001) and the colon by 77% (from 13.8 to 3.1, P=0.01) of DSS-pretreated Apc(MIN/+) mice. In the Apc(MIN/+) group, vandetanib also reduced the mean number of adenomas in the small intestine by 76% (P<0.001) and in the colon by 60% (from 3.9 to 1.5, P=0.1). DSS-pre-treatment increased the resolution of the model, allowing us to confirm statistically significant effects of vandetanib on the development and growth of colon adenomas in the Apc(MIN/+) mouse. Moreover these preclinical data provide a rationale for studying the effects of vandetanib in early stages of intestinal cancer in the clinic.

Topics: Adenoma; Animals; Antineoplastic Agents; beta Catenin; Colitis; Colonic Neoplasms; Dextran Sulfate; Disease Models, Animal; ErbB Receptors; Genes, APC; Intestine, Small; Mice; Mice, Inbred C57BL; Piperidines; Protein Kinase Inhibitors; Quinazolines; Vascular Endothelial Growth Factor Receptor-2

Topics: Adenoma; Adult; Anesthesia, Intravenous; Anesthetics, Intravenous; Blood Pressure; Electroencephalography; Gigantism; Growth Hormone-Secreting Pituitary Adenoma; Humans; Infusions, Intravenous; Intubation, Intratracheal; Male; Monitoring, Intraoperative; Piperidines; Propofol; Remifentanil

The brachial plexus block, either deep or superficial, is one of the anesthetic techniques used in parathyroidectomy. The block is easy to perform and has few hemodynamic side effects. Surgery can be carried out in an awake patient. We describe 3 cases of patients with primary hyperparathyroidism (parathyroid adenoma) who underwent unilateral minimally invasive parathyroidectomy under regional anesthesia and sedation with 2 mg of midazolam plus remifentanil at dosages ranging from 0.6 to 0.1 microg kg(-1) min(-1). To provide a deep cervical block, we administered 15 mL of 0.75% ropivacaine. For a superficial block, 15 mL of 0.2% ropivacaine was used. The procedure could be completed in all 3 patients under regional anesthesia. The latency time for the block ranged from 21 to 30 minutes, and remifentanil dosages from 0.05 to 0.09 microg kg(-1) min(-1) were administered for procedures that lasted 30 to 45 minutes. No patient required postoperative opioids or antiemetics, although a local anesthetic had to be used at the moment of incision for 1 patient. All 3 patients were discharged the same day. We wish to underline the utility of the brachial plexus block for parathyroid surgery. The technique is easy to perform, safe, and effective; as a result, surgery can be carried out on an outpatient basis.

Topics: Adenoma; Aged; Amides; Anesthetics, Local; Autonomic Nerve Block; Brachial Plexus; Conscious Sedation; Female; Humans; Hyperparathyroidism, Primary; Hypnotics and Sedatives; Midazolam; Middle Aged; Minimally Invasive Surgical Procedures; Parathyroid Neoplasms; Parathyroidectomy; Piperidines; Remifentanil; Ropivacaine

Topics: Adenoma; Anti-Obesity Agents; Apoptosis; Carcinoma; Cell Transformation, Neoplastic; Colorectal Neoplasms; Dronabinol; Drug Inverse Agonism; Humans; Inflammatory Bowel Diseases; Intestinal Mucosa; Obesity; Piperidines; Pyrazoles; Receptor, Cannabinoid, CB1; Receptor, Cannabinoid, CB2; Rimonabant

Rat galanin (rGAL) gene expression is stimulated potently by 17 beta-estradiol in the anterior pituitary. Neuroendocrine tissue extracts of were purified by chromatography and analyzed for rGAL-like (-LI) immunoreactivity. Greater than 90% of rGAL-LI eluted at the same position as the synthetic rGAL standard in untreated anterior pituitary, median eminence and neurointermediate lobe tissues. Additional immunoreactive forms were detected in the hypothalamus, anterior pituitary and MtT/W15 adenoma tissues, particularly after 17 beta-estradiol treatment. We examined rGAL and its encoding mRNA in the anterior pituitary of immature female rats after the injection of pregnant mare serum gonadotropin (PMSG). One and two days after PMSG injection, serum 17 beta-estradiol increased 3-fold and 4-fold, respectively. This resulted in a surge of endogenous gonadotropin 2 days after PMSG. At this time, rGAL-encoding mRNA was increased 40-fold over controls. Three days after PMSG, there was a 6-fold increase in anterior pituitary and a 41% increase in plasma rGAL-LI concentrations. Plasma 17 beta-estradiol one day after injection of PMSG and the consequent anterior pituitary rGAL-LI concentrations 2 days later were positively correlated. This stimulation of rGAL and its encoding mRNA by PMSG was inhibited by treatment with the estrogen antagonist keoxifene (LY156758).

Topics: Adenoma; Animals; Chromatography, High Pressure Liquid; Estradiol; Estrogen Antagonists; Female; Galanin; Gene Expression Regulation; Gonadotropins, Equine; Hypothalamus; Neuropeptides; Peptide Biosynthesis; Peptides; Piperidines; Pituitary Gland, Anterior; Radioimmunoassay; Raloxifene Hydrochloride; Rats; Rats, Inbred F344; Rats, Inbred WF; Rats, Sprague-Dawley; RNA, Messenger

Topics: Adenoma; Animals; Benzeneacetamides; Female; Lung Neoplasms; Mice; Piperidines; Piperidones; Urethane

The effect of Antineoplaston A10 (AA10), an amino acid derivative isolated from human urine, has been studied on pulmonary adenoma formation resulting from intragastric administration of benzo(a)pyrene(BP) to A/HeJ mice. Two doses of BP, 3 mg each, administered two weeks apart, induced an average of 6.86 tumours within 157 days in the control animals (Tumorigenic Index 437). One per cent of AA10 (w/w) given in mouse food for one week prior to, and then continued after the administration of BP, produced a 70% reduction in the total number of tumours in the test groups.

Topics: Adenoma; Animals; Antineoplastic Agents; Benzeneacetamides; Benzo(a)pyrene; Body Weight; Female; Lung Neoplasms; Mice; Mice, Inbred A; Piperidines; Piperidones

Chronic oral toxicity and oncogenicity studies on flecainide acetate, an antiarrhythmic compound, were made in male and female rats and mice. The duration of compound administration was 18 months in mice and 24 months in rats, and dose levels for both species were 0, 60, 30, and 15 mg/kg/day. The treated rats had dose-related significant decreases in mean body weights at all dose levels while the treated mice had a small body weight reduction (non-significant) at the higher doses. The body weight effects could not be correlated with reduced food consumption. Chronic administration of flecainide did not produce chronic toxic changes in either species. Likewise, chronic compound administration did not adversely affect survival rates; in fact, the treated groups of rats had survival rates higher than those of the controls with the differences from controls being significant for the male rat groups. All of the tumors in all groups of animals (control and treated) were considered spontaneous in nature. The incidence of the various types of tumors in the treated groups of animals was not significantly increased when compared to the control groups, with one exception. Interstitial cell adenoma in the testes was the most common tumor of the male rats and the increased survival rate of the high dose male rats had a direct effect on the incidence of this tumor. Since the high dose male rats had much better survival than the controls (90% vs 56%), a higher incidence of interstitial cell adenomas would be expected (more rats live longer, more rats with a late developing spontaneous tumor). Comparison of the incidence of interstitial cell adenomas in male rats which survived the 2-year study revealed no significant difference between controls and treated animals. Also when the incidence of interstitial cell adenomas was statistically evaluated with a life table approach, there was no indication of increased tumorigenic risk in the treated groups as compared to the controls.

Topics: Adenoma; Administration, Oral; Animals; Anti-Arrhythmia Agents; Body Weight; Carcinogens; Dose-Response Relationship, Drug; Female; Flecainide; Male; Mice; Organ Size; Piperidines; Rats; Sex Factors; Species Specificity; Time Factors

This study was carried out to test the hypothesis that sustained hyperprolactinaemia in patients with prolactinomas stimulates hypothalamic dopaminergic activity via a short loop positive feedback effect of prolactin (PRL). The intensity of dopamine (DA) effects on the pituitary around the adenoma was evaluated by measuring thyroid stimulating hormone (TSH) responses to intravenous injection of domperidone (10 mg) a new DA receptor blocking drug that does not penetrate the blood-brain barrier. TSH responses have been compared with those of PRL to the same agent. Eight females with prolactinomas showed greater TSH release after domperidone than nine normal females (sum of TSH increments over 20 min 17.5 +/- 1.7 v. 8.9 +/- 1.5 mu/l, P less than 0.001) whilst PRL release was reduced (sum of PRL increments over 120 min 5.9 +/- 2.4 v. 21.8 +/- 3.8 mu/l x 10(-3), P less than 0.01). Amongst nineteen hyperprolactinaemic females with apparently normal pituitary fossae (plain skull X-ray), ten showed an exaggerated TSH response (delta TSH, 4.2 +/- 0.6 mu/l, range 2.5-9.0 mu/1) and reduced PRL response to domperidone, comparable with established tumor cases. In the remaining nine normal fossa hyperprolactinaemic females, the TSH and PRL responses to dopaminergic were similar to normal females. These results support the initial hypothesis and indicate the coexistence of a defect in the dopaminergic inhibition of PRL release and increased dopaminergic inhibition of TSH release in patients with prolactinomas. The presence of an exaggerated TSH response to DA antagonism in a euthyroid, radiologically normal (plain skull X-ray), hyperprolactinaemic patient is compatible with the presence of an autonomously-functioning, PRL secreting, pituitary microadenoma and the TSH changes seen in these patients after DA antagonist administration can be readily detected by sensitive TSH radioimmunoassay.

Topics: Adenoma; Adolescent; Adult; Benzimidazoles; Domperidone; Female; Growth Hormone; Humans; Hydrocortisone; Hypoglycemia; Hypothalamus; Middle Aged; Piperidines; Pituitary Function Tests; Pituitary Gland, Anterior; Pituitary Neoplasms; Prolactin; Thyrotropin; Thyrotropin-Releasing Hormone

Forty-one subjects with hyperprolactinemia underwent testing on separate occasions with nomifensine, an indirectly acting dopamine agonist, and domperidone, a dopamine receptor-blocking agent. Nomifensine (200 mg orally) did not significantly modify plasma levels of prolactin (PRL) in 17 subjects in whom the existence of a pituitary tumor had been established at surgery (12 subjects) or was highly probable (5 subjects). Of the remaining 24 patients with hyperprolactinemia of uncertain etiology, 6 had PRL responsiveness to nomifensine (decrease of baseline PRL levels greater than or equal to 30%) and 18 had PRL unresponsiveness to the drug. The administration of domperidone (4-mg bolus injected intravenously) showed in 36 of the 41 patients the existence of a homogeneity between PRL responsiveness to nomifensine and PRL responsiveness to domperidone. In only five patients was failure of nomifensine to lower plasma PRL levels associated with an increase in plasma PRL levels after domperidone administration (at least doubling of baseline PRL levels). The combined application of nomifensine and domperidone tests holds promise of being a useful method for distinguishing among hyperprolactinemic subjects those with a prolactinoma.

Topics: Adenoma; Adult; Benzimidazoles; Domperidone; Female; Humans; Isoquinolines; Male; Menstruation; Middle Aged; Nomifensine; Piperidines; Pituitary Neoplasms; Postpartum Period; Pregnancy; Prolactin; Sella Turcica

The prolactin (PRL)-releasing effect of domperidone (DOM), a novel antidopaminergic drug which does not cross the blood-brain barrier, was investigated in normoprolactinemic subjects, in subjects with physiologic puerperal hyperprolactinemia or pathological hyperprolactinemia. DOM (4 mg i.v.), administered to 8 normoprolactinemic women, induced a clear-cut and sustained rise in plasma PRL, with peak levels occurring 15-30 min postinjection; the effect of the drug was also evident in 3 normoprolactinemic women at the dose of 0.25 mg i.v. Also in 8 puerperal women (postpartum day 2) intravenous administration of 4 mg DOM was followed by an increase in plasma PRL (51-517% of baseline levels, 15-45 min postinjection). Administration of DOM (4 mg i.v.) to 16 subjects with pathological hyperprolactinemia, evidenced the presence of 14 DOM-nonresponder (maximum percent increase of baseline PRL 48%) and 2 DOM-responder subjects. In 8 of the DOM-nonresponder subjects the existence of a pituitary tumor was established at surgery by selective removal of an adenoma (7 subjects) or a teratoma (1 subject): of the 6 subjects who did not undergo surgery, 3 had biochemical and/or radiologic evidence suggestive of a PRL-secreting tumor and 1 was acromegalic. These results indicate that DOM is capable of releasing PRL both in normoprolactinemic subjects and subjects with puerperal hyperprolactinemia. In contrast, DOM is unable to modify PRL levels in most subjects with pathological hyperprolactinemia, with proven or suspected pituitary tumors.

Topics: Adenoma; Adult; Benzimidazoles; Blood-Brain Barrier; Dopamine Antagonists; Female; Humans; Male; Middle Aged; Piperidines; Pituitary Neoplasms; Postpartum Period; Pregnancy; Prolactin; Teratoma

Dopaminergic receptors were observed on the membranes of 26 human PRL-secreting adenomas. Two binding sites were found for [3H]domperidone, a selective dopamine antagonist, with a Kd1 of 0.29 +/- 0.06 nM and a Kd2 of 4.19 +/- 0.7 nM (n = 5). Bmax1 and Bmax2 (maximum numbers of binding sites, first and second sites, respectively) varied from one adenoma to another. When considering Bmax1, two different categories of PRL-secreting adenomas were distinguished, one with a concentration of receptor over 250 fmol/mg protein and others with lower concentrations of receptor (< 250 fmol/mg protein). In the latter, when considering the volume of the tumor, a higher plasma PRL level was found. Two binding sites for [3H]domperidone also were found in the normal human hypophysis with Kd values similar to those of the adenomas (0.18 +/- 0.04 and 3.95 +/- 0.35 nM). The same number of binding sites was observed in normal pituitaries and in PRL-secreting adenomas. However, when considering the density of PRL-secreting cells in the two different tissues (prolactinomas contain 2 or 3 times more PRL-secreting cells than human pituitary tissue), one may suspect a defect in the dopaminergic inhibiting control in PRL-secreting adenomas.

Topics: Adenoma; Adolescent; Adult; Aged; Benzimidazoles; Binding, Competitive; Cell Membrane; Domperidone; Female; Humans; Kinetics; Male; Middle Aged; Piperidines; Pituitary Gland; Pituitary Neoplasms; Prolactin; Receptors, Dopamine

3H Domperidone binding on cellular membranes from human prolactin adenomas demonstrates the presence of two dopaminergic binding sites. The mean value of the dissociation constant (Kd) for five adenomas is of 0.29 +/- 0.14 nM for the first site and of 4.19 +/- 1.56 nM for the second site. The maximal number of binding sites (Bmax) varies from one adenoma to another. The binding is completely displaced at 30 nM of tritiated Domperidone by apomorohine, a specific dopaminergic agonist.

Topics: Adenoma; Apomorphine; Benzimidazoles; Binding, Competitive; Humans; Kinetics; Piperidines; Pituitary Gland, Anterior; Pituitary Neoplasms; Prolactin; Receptors, Dopamine

Topics: Adenoma; Animals; Arginine; Carcinogens; Female; Hydroxyproline; Lung Neoplasms; Male; Mice; Neoplasms, Experimental; Nitrites; Nitroso Compounds; Piperidines; Proline; Pyrrolidines