Localization of neuropeptide Y mRNA and peptide in the chicken hypothalamus and their alterations after food deprivation, dehydration, and castration.
Localization of neuropeptide Y (NPY) mRNA in the hypothalamus of chickens was studied by in situ hybridization with digoxigenin-labeled chicken NPY cRNA probe. The largest number of perikarya-expressing NPY mRNA was found within the mediobasal hypothalamus, including the infundibular nucleus, inferior hypothalamic nucleus, and median eminence. Many NPY perikarya were noted to surround the nucleus rotundus and to be present in the supraoptic nucleus. Moreover, some perikarya were detected in the nucleus of basal optic root, bed nucleus pallial commissure, and nucleus striae terminalis close to the lateral forebrain bundle. NPY-immunoreactive nerve fibers were densely distributed in these regions containing the NPY mRNA-expressing perikarya. Following food deprivation for four days, perikarya-expressing NPY mRNA and peptide were markedly increased in the mediobasal hypothalamus and particularly so in the infundibular nucleus. No changes, however, were detected in other regions containing NPY-positive perikarya. Water deprivation induced less increase in NPY-positive perikarya in the mediobasal hypothalamus compared to food deprivation. After gonadectomy, the number of NPY-positive perikarya in the mediobasal hypothalamus was unaltered. Northern blot analysis with (32)P-labeled chicken NPY cDNA probe demonstrated that a 2.7-fold increase of NPY mRNA was induced by starvation and a 1.5-fold increase was induced by dehydration, whereas the NPY mRNA band remained unchanged after gonadectomy. Thus, it seems that NPY neurons located in the mediobasal hypothalamus are involved in feeding behavior but not reproductive activity.
Kameda
Y
Y
Department of Anatomy, Kitasato University School of Medicine, Sagamihara, Kanagawa 228, Japan. kameda@med.kitasato-u.ac.jp
Miura
M
M
Nishimaki
T
T
D000818:Animals; D015152:Blotting, Northern; D002645:Chickens / Q000502:physiology*; D003681:Dehydration / Q000473:pathology*; D005508:Food Deprivation / Q000502:physiology*; D007031:Hypothalamus / Q000033:anatomy & histology* / Q000166:cytology / Q000378:metabolism*; D007091:Image Processing, Computer-Assisted; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D008297:Male; D009478:Neuropeptide Y / Q000096:biosynthesis*; D009919:Orchiectomy; D012333:RNA, Messenger / Q000378:metabolism*
D009478:Neuropeptide Y; D012333:RNA, Messenger