Apelin-immunoreactivity in the rat hypothalamus and pituitary.
With the use of an antiserum against human apelin-36, apelin-immunoreactivity (irAP) was detected in neurons and cell processes of the supraoptic nucleus (SO), paraventricular nucleus (PVH), accessory neurosecretory nuclei (Acc) and suprachiasmatic nucleus. Strongly labeled cells/processes were noted in the internal layer of the median eminence, infundibular stem, anterior and posterior pituitary. Double-labeling the sections with goat polyclonal neurophysin I-antiserum and rabbit polyclonal apelin-antiserum revealed a population of magnocellular neurons in the PVH, SO and Acc expressing both irAP and neurophysin I-immunoreactivity (irNP), the latter being a marker of oxytocin-containing neurons. By inference, the AP-positive but irNP-negative magnocellular neurons could be vasopressin-containing. The presence of irAP in certain hypothalamic nuclei and pituitary suggests that the peptide may be a signaling molecule released from the hypothalamic-hypophysial axis.
Department of Pharmacology, James H. Quillen College of Medicine, East Tennessee State University, PO Box 70577, Johnson City, TN 37614, USA.
G Cristina
GC
Brailoiu
Siok L
SL
Dun
Jun
J
Yang
Masahiro
M
Ohsawa
Jaw Kang
JK
Chang
Nae J
NJ
Dun
D000818:Animals; D000073861:Apelin; D002352:Carrier Proteins / Q000032:analysis*; D005260:Female; D007031:Hypothalamus / Q000737:chemistry*; D007150:Immunohistochemistry; D036341:Intercellular Signaling Peptides and Proteins; D008297:Male; D018613:Microscopy, Confocal; D009481:Neurophysins / Q000032:analysis; D010902:Pituitary Gland / Q000737:chemistry*; D051381:Rats; D017207:Rats, Sprague-Dawley
D000073861:Apelin; C498579:Apln protein, rat; D002352:Carrier Proteins; D036341:Intercellular Signaling Peptides and Proteins; D009481:Neurophysins