Immunocytochemical localization of GnRH in the hypothalamus of the bat Miniopterus schreibersii schreibersii.
The distribution of gonadotropin-releasing hormone (GnRH) has been examined in the hypothalamus of adult female bats, Miniopterus schreibersii schreibersii, along annual reproductive cycle by means of light-microscopic immunocytochemistry. GnRH-immunoreactive cells are localized throughout the medial basal hypothalamus, being specially numerous in the arcuate nucleus. They are generally bipolar or monopolar neurons with smooth contour, although spiny cells were also found exclusively in the arcuate nucleus from periovulatory bats. Depletion in both number and immunocytochemical labelling of GnRH perikarya is detected in pregnant and lactating bats. GnRH-immunoreactive fibers are distributed in the internal layer of the median eminence and the infundibular stalk. Pregnant and lactating animals show lower GnRH fibers content and a less intense labelling than in periovulatory and hibernating conditions. The results suggest that changes in the secretory activity of GnRH neurons may be associated with hibernation and delayed implantation that suffer these mammalian species.
Fernández
A M
AM
Department of Cell Biology, Biological Sciences Faculty, Complutense University, Madrid, Spain.
Muñiz
E
E
Gragera
R R
RR
Martínez-Rodríguez
R
R
D000818:Animals; D001111:Arcuate Nucleus of Hypothalamus / Q000378:metabolism; D002685:Chiroptera / Q000502:physiology*; D005260:Female; D007987:Gonadotropin-Releasing Hormone / Q000378:metabolism*; D006605:Hibernation / Q000502:physiology; D007031:Hypothalamus / Q000033:anatomy & histology / Q000378:metabolism*; D007150:Immunohistochemistry; D008473:Median Eminence / Q000033:anatomy & histology / Q000502:physiology; D009412:Nerve Fibers / Q000378:metabolism; D010060:Ovulation / Q000378:metabolism
D007987:Gonadotropin-Releasing Hormone