Andres Negro-Vilar

The ovarian renin-angiotensin system: Renin-like activity and angiotensin II/III immunoreactivity in gonadotropin-stimulated and unstimulated human follicular fluid☆☆☆

Abstract Renin-like activity and angiotensin II/III immunoreactivity in follicular fluids from 34 women stimulated with human menopausal gonadotropin and human chorionic gonadotropin (56.8 ± 6.5 ng angiotensin I per milliliter per hour and 187 ± 21 pg/ml [mean ± SEM], respectively) were much higher (p

Role of Galanin in the Regulation of Somatotrope and Gonadotrope Function in Young Ovulatory Women

The aim of the study was to elucidate the role of the neuropeptide galanin in the regulation of somatotropic and gonadotropic function in normal women. Thirteen normally ovulating (aged 28 to 40 years), non-obese (body mass index, 18.4 to 27.1 kg/m2) women with infertility due to a tubal or male factor were studied. Each woman underwent three tests: (1) bolus intravenous (IV) injection of growth hormone (GH)-releasing hormone (GHRH) (1-29)NH2 1 microgram/kg plus gonadotropin-releasing hormone (GnRH) 100 micrograms at time 0; (2) IV infusion of porcine galanin 500 micrograms in 100 mL saline from -10 minutes; and (3) bolus IV injection of GHRH(1-29)NH2 1 microgram/kg plus GnRH 100 micrograms at time 0 plus IV infusion of porcine galanin 500 micrograms in 100 mL saline from -10 to +30 minutes. All results are expressed as the mean +/- SEM. GH peak after GHRH was 14 +/- 5 micrograms/L; porcine galanin significantly increased serum GH (GH peak, 7.3 +/- 1.2) with respect to baseline levels. No significant differences were observed between either GH peak or GH absolute values after galanin as compared with GHRH alone. Porcine galanin significantly enhanced GH response to GHRH (peak, 31.4 +/- 4.4 micrograms/L) with respect to either GHRH or galanin alone. Luteinizing hormone (LH)/follicle-stimulating hormone (FSH) peaks after GnRH were 16.5 +/- 5.3 and 17.4 +/- 4 IU/L, respectively. Porcine galanin did not cause significant increases in serum LH and FSH levels with respect to baseline.(ABSTRACT TRUNCATED AT 250 WORDS)

Localization of Inhibin Alpha-Subunit Immunoreactivity in the Rat Adrenal Cortex

Inhibin, a water soluble, non‐steroidal glycoprotein hormone that inhibits follicle‐stimulating hormone secretion, is produced by the gonads and several non‐gonadal tissues (placenta, pituitary and brain). This study describes the presence of inhibin α‐chain‐immunoreactive cells in the adrenal cortex of intact adult male rats and the effects of hypophysectomy and adrenocorticotropin treatment on the expression of inhibin in that gland. In intact rats, the majority of the immunoreactive cells were found scattered in the zona glomerulosa and reticularis. The zona fasciculata contained only a few cells immunopositive for the inhibin α‐chain. No immunoreactive cells were found in the medulla. Hypophysectomy resulted in a dramatic reduction in α‐subunit immunoreactivity with only scattered cells observed in the zona glomerulosa and reticularis (0 to 2 cells/section). No immunoreactive cells were found in the zona fasciculata or the medulla. Following supraphysiologic adrenocorticotropin administration to hypophysectomized animals, the number of inhibin α‐chain‐immunoreactive cells significantly increased in each zone of the adrenal cortex. The most prominent changes were seen in the zona reticularis. Interestingly, in the adrenocorticotropin‐treated animals scattered immunopositive cells were also present in the medulla. Our results suggest that inhibin‐related peptide(s) exist within the adrenal gland and that the expression of these peptides is regulated by adrenocorticotropin. Inhibin‐related peptide(s) may, therefore, play a paracrine and/or endocrine role in the adrenal function.