ABSTRACT
I. Introduction..................................................................................... 9 II. Migration of LHRH Cells into the CNS...................................... 10
A. Olfactory/Vomeronasal Axonal Tracks.................................. 11 B. Movements of LHRH Cells in Nasal Regions....................... 11 C. Nasal/Forebrain Junction ....................................................... 12
III. Properties of LHRH Neurons outside the CNS ......................... 14 A. Biosynthesis and Secretion of LHRH Peptide ...................... 14
IV. Conclusions and Future Issues .................................................... 15 References ............................................................................................... 16
The neuroendocrine luteinizing hormone-releasing hormone (LHRH) neuronal system is essential for reproductive function in vertebrates (reviewed in reference 1). Numbering from 800 to 2000 in mammals (reviewed in reference 2), LHRH neurons within the central nervous system (CNS) are distributed bilaterally, in a continuum from the olfactory bulbs to the caudal hypothalamus (reviewed in references 2 to 4). The main axonal target of these neuroendocrine LHRH neurons is the median eminence, specifically the fenestrated capillaries of the hypothalamo-pituitary portal capillary system (reviewed in references 2 to 4). Release of LHRH at this site is pulsatile and affects the synthesis and secretion of gonadotropins, and consequently activation of gonadal function (reviewed in references 1 and 3).
