biostudies-literatureSingh RNICHD NIH HHSNHLBI NIH HHS3672-7https://www.ebi.ac.uk/biostudies/studies/S-EPMC16298biostudies-literatureUnknown97(7)Sex differences in nitric oxide synthase (NOS) activity in different regions of the rat brain and effects of testosterone and dihydrotestosterone (DHT) treatment in orchidectomized animals were investigated. Regional but no sex differences in NOS activity were detected in gonadectomized animals. Orchidectomy significantly increased NOS activity in the hypothalamus, "amygdala," and cerebellum but not in the cortex. In the hypothalamus, the increase in NOS activity after castration and its reversal by androgen treatment was mimicked by changes in neuronal NOS mRNA level. In contrast, androgen receptor (AR) mRNA level in the hypothalamus was slightly reduced by castration and increased by treatment with DHT. Again in the hypothalamus, the increase in NOS activity in castrated rats was accompaProceedings of the National Academy of Sciences of the United States of AmericaCastration increases and androgens decrease nitric oxide synthase activity in the brain: physiologic implications.PMC16298HD-35991HL-46843HD-01182R01 HD035991Shryne JChaudhuri GSingh RPervin SGorski RfalseCastration increases and androgens decrease nitric oxide synthase activity in the brain: physiologic implications.Sex differences in nitric oxide synthase (NOS) activity in different regions of the rat brain and effects of testosterone and dihydrotestosterone (DHT) treatment in orchidectomized animals were investigated. Regional but no sex differences in NOS activity were detected in gonadectomized animals. Orchidectomy significantly increased NOS activity in the hypothalamus, "amygdala," and cerebellum but not in the cortex. In the hypothalamus, the increase in NOS activity after castration and its reversal by androgen treatment was mimicked by changes in neuronal NOS mRNA level. In contrast, androgen receptor (AR) mRNA level in the hypothalamus was slightly reduced by castration and increased by treatment with DHT. Again in the hypothalamus, the increase in NOS activity in castrated rats was accompa2000-01-01T00:00:00Z2000 Mar2025-04-04T08:21:27.46Z2019-03-27T00:17:45ZS-EPMC162981072537110.1073/pnas.97.7.3672