We demonstrate here that highly sensitive in vitro bioassays for FSH, TSH, and PTH can be set up in mouse Leydig Tumor Cells (mLTC), in addition to the normal LH/CG bioassay, after they were transfected with expression vectors encoding the corresponding Gs Protein-Coupled Receptors (GsPCR), such as FSHR, TSHR, or PTHR. Although the β2 adrenergic receptor is also a GsPCR, its expression in mLTC led to a significant but very low cAMP response compared to those observed with FSH, TSH, or PTH. Similarly, after transfection of the GiPCR MT1 melatonin receptor, we did not observe any inhibitory effect by melatonin of the LH or hCG stimulation.
View Article and Find Full Text PDFThis article reviews the scientific literature on puberty with a focus on ruminants and draws inference, where appropriate, from recent findings in transgenic mouse models and human pathology. Early genetic determinants of puberty have been discovered in humans suffering from hypogonadotropic hypogonadism or central precocious puberty. Transgenic mouse models selected on the basis of the causative defective genes helped in discovering the cellular and molecular mechanisms involved.
View Article and Find Full Text PDFReprod Domest Anim
September 2023
Pulsatile secretion of gonadotropin-releasing hormone (GnRH) is essential for the activation and maintenance of the function of the hypothalamic-pituitary-gonadal (HPG) axis, which controls the onset of puberty and fertility. Two provocative recent studies suggest that, in addition to control reproduction, the neurons in the brain that produce GnRH are also involved in the control postnatal brain maturation, odour discrimination and adult cognition. Long-acting GnRH antagonists and agonists are commonly used to control fertility and behaviour in veterinary medicine, primarily in males.
View Article and Find Full Text PDFIn mammals, reproductive function is under the control of hypothalamic neurons named Gonadotropin-Releasing Hormone (GnRH) neurons. These neurons migrate from the olfactory placode to the brain, during embryonic development. For the past 40 years, these neurons have been considered an example of tangential migration, i.
View Article and Find Full Text PDFHypothalamic control of reproduction relies on GnRH and kisspeptin (KP) secretions. KP neurons are sensitive to sex steroids and metabolic status and their distribution overlaps with neurons producing apelin, a metabolic hormone known to decrease LH secretion in rats. Here, we observed neuroanatomical contacts between apelin fibers and both KP and GnRH neurons in the hypothalamus of male rodents.
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