The potential sexual differentiation in the Gonadotropin-Releasing Hormone Neuron Count in the Rostral Preoptic Area of a Mouse.
The potential sexual differentiation in the Gonadotropin-Releasing Hormone Neuron Count in the Rostral Preoptic Area of a Mouse.
Abstract
It is known that the HPG axis is sexually differentiated in GnRH neuron populations. In mice this is seen to be sexually differentiated in the secretary patterns of the synaptic projections instead of the cell count itself. This experiment proves that it is not the cell count of GnRH neurons that is sexually differentiated by conducting a single label immunohistochemistry to fluoresce GnRH neurons in the rostral preoptic area while comparing the cell numbers in male female mice. Similar previous cell count experiments are backed up while the suggested part of the GnRH neurons that is sexually differentiated is discussed.
Introduction
Gonadotropin-releasing hormone (GnRH) is a peptide hormone that regulates the sexual maturation of mammals from the anterior pituitary gland. GnRH originates in the nasal placode (Funabashi et al., 2002) and migrates to the central nervous system during embryogenesis (Eisthen et al., 2000). There are several prominent locations of GnRH neurons in and out of the central nervous system including the rostral preoptic area (rPOA) which is the area of interest for this study. GnRH neurons specifically in the rPOA regulate the secretion of the gonadotropic hormones luteinising hormone (LH) and follicle stimulating hormone (FSH) (Eisthen et al., 2000; Suter et al., 2000).
From previous studies it is known that the Hypothalamo-pituitary-gonadal (HPG) axis is sexually differentiated. In females the hormone released is predominantly estrogen which provides negative and positive feedback to the GnRH neurons during the ovarian cycle. In males the main hormone is testosterone, which is aromatized to estrogen. This provides constant negative feedback to GnRH neurons (Herbison, 2008; Clarkson & Herbison, 2009). This leads to the question of what part in the HPG axis is sexually differentiated and whether it
Abstract
It is known that the HPG axis is sexually differentiated in GnRH neuron populations. In mice this is seen to be sexually differentiated in the secretary patterns of the synaptic projections instead of the cell count itself. This experiment proves that it is not the cell count of GnRH neurons that is sexually differentiated by conducting a single label immunohistochemistry to fluoresce GnRH neurons in the rostral preoptic area while comparing the cell numbers in male female mice. Similar previous cell count experiments are backed up while the suggested part of the GnRH neurons that is sexually differentiated is discussed.
Introduction
Gonadotropin-releasing hormone (GnRH) is a peptide hormone that regulates the sexual maturation of mammals from the anterior pituitary gland. GnRH originates in the nasal placode (Funabashi et al., 2002) and migrates to the central nervous system during embryogenesis (Eisthen et al., 2000). There are several prominent locations of GnRH neurons in and out of the central nervous system including the rostral preoptic area (rPOA) which is the area of interest for this study. GnRH neurons specifically in the rPOA regulate the secretion of the gonadotropic hormones luteinising hormone (LH) and follicle stimulating hormone (FSH) (Eisthen et al., 2000; Suter et al., 2000).
From previous studies it is known that the Hypothalamo-pituitary-gonadal (HPG) axis is sexually differentiated. In females the hormone released is predominantly estrogen which provides negative and positive feedback to the GnRH neurons during the ovarian cycle. In males the main hormone is testosterone, which is aromatized to estrogen. This provides constant negative feedback to GnRH neurons (Herbison, 2008; Clarkson & Herbison, 2009). This leads to the question of what part in the HPG axis is sexually differentiated and whether it