title: Comparative study of the sources of neuronal projections to the site of gonadotrophin-releasing hormone perikarya and to the anteroventral periventricular nucleus in female rats.
abstract: The rat ovulatory cycle is dependent on the preoptic region encompassing the gonadotrophin-releasing hormone (GnRH) perikarya and the anteroventral periventricular nucleus (AVPV). Retrograde tract tracing was used to identify and compare the sources of inputs to these sites in female rats. Within the telencephalon and diencephalon, the incidence of retrograde labelling from both sites was moderate to abundant in the ventral lateral septum, posteromedial bed nucleus of the stria terminalis, amygdalohippocampal area and the periventricular, medial preoptic, anterodorsal preoptic, dorsomedial suprachiasmatic, arcuate, and posterior ventrolateral ventromedial hypothalamic nuclei. In these regions, the incidence of retrograde labelling was either greater from the AVPV than from the GnRH perikarya site or similar from both sites. In the medial amygdaloid, parastrial, striohypothalamic, and ventral premammillary nuclei, the retrograde labelling from the AVPV greatly exceeded the sparse incidence from the GnRH perikarya site. In contrast, retrograde labelling from the GnRH perikarya site predominated in the median preoptic, lateroanterior and dorsomedial hypothalamic nuclei, subparaventricular zone, and retrochiasmatic area; it was abundant in the AVPV. Caudal to the diencephalon, retrograde labelling from either site was sparse, except in the lateral parabrachial nucleus, which displayed a particularly high incidence from the GnRH perikarya site. Other mesencephalic regions labelled from either site included the periaqueductal gray and dorsal and median raphe nuclei. The most caudal labelling was found in the ventrolateral medulla and region of the solitary tract nucleus; this was almost exclusively from the GnRH perikarya site. These findings further elucidate the neuroanatomical connections underlying the control of the ovulatory cycle.
authors.affiliation: School of Biomedical Sciences, King's College London, SE1 1UL, United Kingdom.
authors.forename: Joel D
authors.initials: JD
authors.lastname: Hahn
authors.forename: Clive W
authors.initials: CW
authors.lastname: Coen
mesh_terms: D000818:Animals; D007025:Anterior Hypothalamic Nucleus / Q000166:cytology* / Q000378:metabolism; D001931:Brain Mapping; D002772:Cholera Toxin / Q000378:metabolism; D004027:Diencephalon / Q000166:cytology / Q000378:metabolism; D005260:Female; D007987:Gonadotropin-Releasing Hormone / Q000378:metabolism*; D007150:Immunohistochemistry / Q000379:methods; D016571:Neural Networks, Computer; D009434:Neural Pathways / Q000166:cytology* / Q000378:metabolism; D009474:Neurons / Q000166:cytology / Q000378:metabolism*; D010052:Ovariectomy / Q000379:methods; D051381:Rats; D017208:Rats, Wistar; D013687:Telencephalon / Q000166:cytology / Q000378:metabolism
chemical_list: D007987:Gonadotropin-Releasing Hormone; D002772:Cholera Toxin