neurokinin-a and Body-Weight

Aim Determine changes in the expressions of the ion channel-TRPV1-and neuropeptides-NKA, NKB, calcitonin gene-related peptide (CGRP), and SP-in 14-, 21-, and 42-day-old rats after inhaling 1.5% and 2.6% sevoflurane.. A small in-house inhalation anesthesia chamber was designed to allow 14-, 21-, and 42-day-old rats inhale 1.5% and 2.6% sevoflurane, and rats in the control group inhaled carrier gas(1 L/min air +1 L/min O. After inhalation of 1.5% sevoflurane, the expression of TRPV1 in the lung tissues of 14- and 21-day-old rats was significantly increased compared with that in the control group, which was antagonized by capsazepine pretreatment. Moreover, inhalation of 1.5% sevoflurane markedly increased the expressions of NKA, NKB, CGRP, and SP in the trachea of 21-day-old rats and of NKB, CGRP, and SP in the trachea of 14-day-old rats. The expressions of these molecules were antagonized by capsazepine pretreatment. Conversely, inhalation of 2.6% sevoflurane decreased the expressions of NKA and NKB in the trachea of 42-day-old rats.. Sevoflurane did not upregulate the expression of TRPV1 in the airways of late-developing rats. This anesthetic may have a two-way effect on airways, resulting in considerable effects in pediatric clinical anesthesia management.

Topics: Administration, Inhalation; Age Factors; Anesthetics, Inhalation; Animals; Blood Gas Analysis; Body Weight; Calcitonin Gene-Related Peptide; Capsaicin; Dose-Response Relationship, Drug; Neurokinin A; Neurokinin B; Rats; Rats, Sprague-Dawley; Respiration; Sevoflurane; Substance P; Trachea; TRPV Cation Channels

Evidence implies a role for corticotropin-releasing hormone (CRH) and tachykinins, e.g. substance P (SP) and neurokinin A (NKA) in the pathophysiology of depression. We have previously shown that SP- and NKA-like immunoreactivity (-LI) concentrations were altered in the frontal cortex and striatum of the congenitally 'depressed' Flinders Sensitive Line (FSL) compared to the Flinders Resistant Line (FRL) control rats. It is also known that environmental stress may affect brain levels of tachykinins. In view of these results we decided to superimpose maternal deprivation, an early life environmental stressor, onto the genetically predisposed 'depressed' FSL rats and the FRL control rats and use this paradigm as a model of gene-environment interaction. The adult animals were sacrificed, adrenal glands and brains dissected out and SP-, NKA- and CRH-LI levels were determined in ten discrete brain regions. Maternal deprivation led to a marked increase in SP-LI and NKA-LI levels in the periaqueductal grey (PAG) and entorhinal cortex of the 'depressed' FSL strain while it had no significant effect in the FRL controls. Furthermore, specific strain differences in peptide-LI content were confirmed. No difference was found in relative adrenal gland weight, which is consistent with the finding that CRH-LI levels in the hypothalamus were similar across strains, and insensitive to stress in either strain. Taken together, these data are in line with behavioural experiments showing ameliorating effects of NK1 and NK2 receptor antagonists against anxiety and depression-like symptoms in rodents, and therefore further implicate the tachykinin systems in the pathophysiology of depression and adult life psychopathology.

Topics: Adrenal Glands; Animals; Anxiety, Separation; Body Weight; Corticotropin-Releasing Hormone; Depression; Entorhinal Cortex; Immunochemistry; Male; Neurokinin A; Occipital Lobe; Organ Size; Periaqueductal Gray; Prefrontal Cortex; Rats; Rats, Sprague-Dawley; Social Isolation; Substance P

Environmental factors, such as adverse life experiences and family/peer influences have a substantial influence on the development of disorders related to alcohol use. In animals, maternal or peer separation/isolation has been used as an environmental intervention that has been shown to alter neurodevelopment and influence drinking behaviors in rodents and primates. In this study, the effects of adult peer isolation on subsequent ethanol intake were investigated in Wistar rats. Because central tachykinin levels have been reported to differ between rats selected for enhanced ethanol preference, neuropeptide [neurokinin A (NKA), substance P (SP)] concentrations were also estimated. Lower levels of ethanol intake, in a two-bottle free-choice model, were observed on the first day of forced ethanol drinking in the single-housed animals. However, overall ethanol consumption was unaffected by peer isolation. Peer isolation significantly lowered SP and NKA levels in the hypothalamus, but this effect was not related to ethanol consumption or body weight. These data indicate that endogenous SP and neurokinin levels are reduced by isolation housing, but this was not associated with alterations in drinking levels using a two-bottle choice procedure.

Topics: Alcohol Drinking; Animals; Body Weight; Brain Chemistry; Male; Neurokinin A; Radioimmunoassay; Rats; Rats, Wistar; Social Isolation; Substance P; Tachykinins

The developmental changes of hypothalamic and anterior pituitary tachykinin concentrations were studied in female Siberian hamsters kept either under short (SD) or long (LD) daily photoperiods. The animals were killed between 15 and 70 days of age. Hypothalamic NKA sharply increased starting at 15 days up to 50 days in LD animals, and between 20 and 60 days in SD animals. Hypothalamic SP levels increased in a similar manner in SD animals, but in LD animals the increment was less pronounced, with increased levels from day 20 to 40, followed by a plateau. In the anterior pituitary gland, NKA concentrations in LD animals increased at 40 days of age, with only slight increases afterward, but overall the increment curve was considerably flatter than for hypothalamic NKA. In SD animals, the increase of anterior pituitary NKA was much steeper than in LD animals. However, the total content of NKA in the AP was similar in both SD and LD animals, because the AP weight was considerably higher in LD- than in SD-exposed hamsters. These results showed that photoperiod did not markedly affect the developmental changes in hypothalamic NKA. The developmental changes in anterior pituitary NKA concentrations were considerably smaller than in the hypothalamus in LD animals, but in SD animals they were much steeper. NKA concentrations in the anterior pituitary were markedly affected by the photoperiod. Concentrations of NKA in the anterior pituitary of the Siberian hamster at the age of 15 days of age were already higher than in the anterior pituitary of adult rats or Syrian hamsters.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Aging; Animals; Body Weight; Circadian Rhythm; Cricetinae; Darkness; Female; Hypothalamus; Light; Neurokinin A; Organ Size; Ovary; Phodopus; Pituitary Gland, Anterior; Rats; Sexual Maturation; Species Specificity; Substance P; Uterus