The present study was carried out to determine the effects of chronic exposure to social stress during puberty on the dopamine system in male golden hamsters. Experimental animals were socially subjugated between postnatal days 28 (P28) and 42. All animals were sacrificed on P46 and their brains processed for immunocytochemistry to tyrosine hydroxylase (TH). A large increase in the number of TH...

Rodents exposed to a 15-min pretest swim in the forced swimming test (FST) exhibit prolonged immobility in a subsequent 5-min test swim, and antidepressant treatment before the test swim reduces immobility. At present, neuronal circuits recruited by antidepressant before the test swim remain unclear, and also less is known about whether antidepressants with different mechanisms of action could ...

Testosterone and its metabolites are the principal gonadal hormones responsible for sexual differentiation of the brain. However, the relative roles of the androgen receptor (AR) vs. the estrogen receptor in specific aspects of this process remain unclear due to the intracellular metabolism of testosterone to active androgenic and estrogenic compounds. In this study, we used an 35S-labeled ribo...

Regulation of ACTH secretion changes between early (40 d) and late (60 d) puberty in male rats. We tested whether this occurs because of activating effects of testosterone on the brain. We measured testosterone and ACTH responses to repeated restraint in adrenalectomized, corticosterone-replaced rats entering and leaving puberty with or without treatment with flutamide, a nonsteroidal androgen-...

This study has examined whether circulating estrogens are involved in regulating gamma-aminobutyric acid (GABA)A receptor mRNA expression in regions of the female rat brain known to contain estrogen receptors (ERs). In situ hybridization experiments using 35S-labeled oligonucleotides specific for alpha 2, beta 3, and gamma 1 subunit mRNAs of the GABAA receptor demonstrated that all three mRNAs ...

Calcitonin gene-related peptide (CGRP) evokes anxiety-like responses when infused into the lateral ventricle of rats. Because the bed nucleus of the stria terminalis (BNST) lies immediately adjacent to the lateral ventricle, is rich in CGRP receptors, and has itself been implicated in anxiety, we evaluated the hypothesis that these effects are attributable to stimulation of CGRP receptors withi...

Urocortin (Ucn) III, or stresscopin, is a new member of the corticotropin-releasing factor (CRF) peptide family identified in mouse and human. Pharmacological studies showed that Ucn III is a high-affinity ligand for the type 2 CRF receptor (CRF-R2). To further understand physiological functions the peptide may serve in the brain, the distribution of Ucn III neurons and fibers was examined by i...

introduction: gonadotropin inhibitory hormone (gnih) is believed to be an inhibitor of gonadotropin releasing hormone (gnrh) secretion. the role of gnih in lactational inhibition of gonadotropin secretion is not well known therefore, the aim of the present study was to evaluate the effect of lactation on expression of gnih in these nuclei of lactating and non-lactating rats. methods: ten postpa...

The medial preoptic area (MPOA), bed nucleus of the stria terminalis (BNST), and medial amygdaloid nucleus (Me) are essential for male sexual behavior in the Syrian hamster. These nuclei received chemosensory stimuli and gonadal steroid signals, both of which are required for mating behavior. The objective of this study was to compare the distribution of androgen- and estrogen-concentrating neu...