Deletion of GABAB receptors from cells affects glucose homeostasis without altering reproduction in male mice.

Kisspeptin and γ-amino butyric acid (GABA), synthesized in the central nervous system, are critical for reproduction. Both are also expressed in peripheral organs/tissues critical to metabolic control (liver/pancreas/adipose). Many kisspeptin neurons coexpress GABAB receptors (GABABR) and GABA controls kisspeptin expression and secretion.

Chronic exposure to low concentrations of chlorpyrifos affects normal cyclicity and histology of the uterus in female rats.

Chlorpyrifos (CPF), the most used insecticide in Argentina, can act as an endocrine disruptor at low doses. We previously demonstrated that chronic exposure to CPF induces hormonal imbalance in vivo. The aim of this work was to study the effects of low concentrations of CPF (0.

Multiple failures in the lutenising hormone surge generating system in GABAB1KO female mice.

Female mice lacking GABAB receptors, GABAB1KO, show disrupted oestrous cycles, reduced pregnancies and increased hypothalamic Gnrh1 mRNA expression, whereas anteroventral periventricular/periventricular preoptic nucleus (AVPV/PeN) Kiss1 mRNA was not affected. In the present study, we characterise the important components of the gonadotrophic preovulatory surge, aiming to unravel the origin of this reproductive impairment. In GABAB1KO and wild-type (WT) females, we determined: (i) hypothalamic oestrogen receptor (ER)α and β and aromatase mRNA and protein expression; (ii) ovulation index and oestrus serum follicle-stimulating hormone (FSH) and pituitary Gnrh1r expression; (iii) in ovariectomised-oestradiol valerate-treated mice, we evaluated ex vivo hypothalamic gonadotrophin-releasing hormone (GnRH) pulsatility in the presence/absence of kisspeptin (Kiss-10, constant or pulsatile) and oestradiol (constant); and (iv) in ovariectomised-oestradiol silastic capsule-treated mice (proestrous-like environment), we evaluated morning and evening kisspeptin neurone activation (c-Fos+) and serum luteinising homrone (LH).

Neonatal exposure to bisphenol A alters the hypothalamic-pituitary-thyroid axis in female rats.

Bisphenol A (BPA) is a component of polycarbonate plastics, epoxy resins and polystyrene found in many common products. Several reports revealed potent in vivo and in vitro effects. In this study we analyzed the effects of the exposure to BPA in the hypothalamic-pituitary-thyroid axis in female rats, both in vivo and in vitro.

Evaluation of sodium arsenite exposure on reproductive competence in pregnant and postlactational dams and their offspring.

We investigated arsenite exposure on the reproductive axis of dams (during pregnancy and at cyclicity resumption) and their offspring. Pregnant rats were exposed to 5 (A5) or 50ppm (A50) of sodium arsenite in drinking water from gestational day 1 (GD1) until sacrifice at GD18 or two months postpartum. Offspring were exposed to the same treatment as their mothers from weaning to adulthood.

Arsenite in drinking water produces glucose intolerance in pregnant rats and their female offspring.

Drinking water is the main source of arsenic exposure. Chronic exposure has been associated with metabolic disorders. Here we studied the effects of arsenic on glucose metabolism, in pregnant and post-partum of dams and their offspring.

Pesticide chlorpyrifos acts as an endocrine disruptor in adult rats causing changes in mammary gland and hormonal balance.

Endocrine disruptors (EDs) are compounds that interfere with hormone regulation and influence mammary carcinogenesis. We have previously demonstrated that the pesticide chlorpyrifos (CPF) acts as an ED in vitro, since it induces human breast cancer cells proliferation through estrogen receptor alpha (ERα) pathway. In this work, we studied the effects of CPF at environmental doses (0.

Non-invasive endocrine monitoring of ovarian and adrenal activity in chinchilla (Chinchilla lanigera) females during pregnancy, parturition and early post-partum period.

The chinchilla is a rodent that bears one of the finest and most valuable pelts in the world. The wild counterpart is, however, almost extinct because of a drastic past and ongoing population decline. The present work was developed to increase our knowledge of the reproductive physiology of pregnancy and post-partum estrus in the chinchilla, characterizing the endocrine patterns of urinary progesterone, estradiol, LH and cortisol metabolites throughout gestation and post-partum estrus and estimating the ovulation timing at post-partum estrus.

Prenatal maternal restraint stress exposure alters the reproductive hormone profile and testis development of the rat male offspring.

Several studies have demonstrated that the presence of stressors during pregnancy induces adverse effects on the neuroendocrine system of the offspring later in life. In the present work, we investigated the effects of early programming on the male reproductive system, employing a prenatal stress (PS) paradigm. This study found that when pregnant dams were placed in a plastic restrainer three times a day during the last week of pregnancy, the offspring showed reduced anogenital distance and delayed testicular descent.

Neonatal xenoestrogen exposure alters growth hormone-dependent liver proteins and genes in adult female rats.

The hypothalamic-growth hormone (GH)-liver axis represents a new concept in endocrine regulation of drug toxicity. Preponderant sex differences are found in liver gene expression, mostly dependent on the sexually dimorphic pattern of GH secretion which is set during the neonatal period by gonadal steroids. We tested if GH-dependent sexually dimorphic liver enzymes and proteins was perturbed by neonatal Bisphenol A (BPA) treatment in female rats.

Alterations in c-Src/HER1 and estrogen receptor α signaling pathways in mammary gland and tumors of hexachlorobenzene-treated rats.

Hexachlorobenzene (HCB) is an organochlorine pesticide that acts as an endocrine disruptor in humans and rodents. The development of breast cancer strongly depends on endocrine conditions modulated by environmental factors. We have demonstrated that HCB is a tumor co-carcinogen in rats and an inducer of proliferation in MCF-7 cells, in an estrogen receptor α (ERα)-dependent manner, and of migration in MDA-MB-231 breast cancer cell line.

Neonatal exposure to bisphenol a and reproductive and endocrine alterations resembling the polycystic ovarian syndrome in adult rats.

Background: Bisphenol A (BPA), an endocrine disruptor, is a component of polycarbonate plastics, epoxy resins, and polystyrene. Several studies have reported potent in vivo effects, because BPA behaves as an estrogen agonist and/or antagonist and as an androgen and thyroid hormone antagonist.

Objectives: We investigated the effects of neonatal exposure to BPA on the reproductive axis in adult female Sprague-Dawley rats.