Gonadotropin-releasing hormone (GnRH) is a neuropeptide hormone responsible for the release of luteinizing hormone (Lh) and follicle-stimulating hormone (Fsh) from the anterior pituitary gland . GnRH have been identified and characterized from the brain of C. catla. A cDNA fragment of 202bp was amplified and GnRH variant has been identified in the form chicken-II-type gonadotropin-releasing hor...

The role of RNA synthesis was investigated in the action of chorionic gonadotropin on ovaries of immature rats. Chorionic gonadotropin accelerates the ovarian incorporation of [3H]uridine in uivo into rapidly labeled nuclear RNA within 10 min after hormone injection. Analysis of the RNA base composition, expressed as base ratio (A + U):(G + C), shows that hormonal stimulation of the rate of [3H...

Seasonal mammals use the photoperiodic variation in the nocturnal production of the pineal hormone melatonin to synchronize their reproductive activity with seasons. In rodents, the (SD) short day profile of melatonin secretion has long been proven to inhibit reproductive activity. Lately, we demonstrated that melatonin regulates the expression of the hypothalamic peptides kisspeptins (Kp) and ...

The steroidogenic lesion produced in Leydig cells by gonadotropin stimulation has been attributed to an inhibitory effect of estrogen on 17a-hydroxylase and 17,20-desmolase activity, with impaired conversion of progesterone to androgens. In animals treated with doses of human chorionic gonadotropin (hCG) or gonadotropin-releasing hormone (GnRH) that caused the decrease in desmolase activity, ad...

Natural variation in neuroendocrine traits is poorly understood, despite the importance of variation in brain function and evolution. Most rodents in the temperate zones inhibit reproduction and other nonessential functions in short winter photoperiods, but some have little or no reproductive response. We tested whether genetic variability in reproductive seasonality is related to individual di...

objective: the appropriate interaction between a blastocyst and the endometrium is essential for successful implantation. numerous factors, including hormone receptors (progesterone receptor), cytokines [leukemia inhibitory factors (lif)], and adherence molecules such as e-cadherin are involved in the cross-talk that occurs between the embryo and endometrium. studies show that a lack of these g...

Abstract Polycystic Ovarian Syndrome (PCOS) is a disease that characterized by an increased Gonadotropin-Releasing-Hormone (GnRH) pulsatile frequency, causing altered LH/FSH ratio. More precisely Luteinizing Hormone (LH) secretion compared to decreased Follicle-Stimulating (FSH) leads the development of hyperandrogenism and low-level concentration estrogens therefore negative estrogenic feedbac...