Direct and indirect modulation of neuropeptide Y gene expression in response to hypoglycemia in rat arcuate nucleus.
Expression of neuropeptide Y (Npy) heteronuclear (hn) RNA, an indicator of gene transcription, was significantly increased in the arcuate nucleus of rats 30min after insulin injection. Npy hnRNA levels were also increased significantly in response to hypoglycemia in rats in which the hypothalamus was deafferentated, although the absolute levels were significantly lower than in sham-operated rats. Direct effects of lowering glucose levels on Npy gene expression were also confirmed in hypothalamic organotypic cultures. Thus, Npy gene transcription in the arcuate nucleus increases rapidly in response to hypoglycemia, and both direct and indirect inputs are involved in the rapid upregulation.
Department of Endocrinology and Diabetes, Nagoya University Graduate School of Medicine, Showa-ku, Nagoya 466-8550, Japan.
Minemori
M
Watanabe
Hiroshi
H
Arima
Kuriko
K
Fukushima
Motomitsu
M
Goto
Hiroshi
H
Shimizu
Masayuki
M
Hayashi
Ryoichi
R
Banno
Ikuko
I
Sato
Nobuaki
N
Ozaki
Hiroshi
H
Nagasaki
Yutaka
Y
Oiso
D000818:Animals; D001111:Arcuate Nucleus of Hypothalamus / Q000378:metabolism*; D001786:Blood Glucose / Q000378:metabolism*; D003470:Culture Media / Q000494:pharmacology; D015870:Gene Expression / Q000187:drug effects; D005786:Gene Expression Regulation; D005947:Glucose / Q000494:pharmacology; D007003:Hypoglycemia / Q000235:genetics* / Q000378:metabolism; D008297:Male; D009478:Neuropeptide Y / Q000235:genetics*; D009924:Organ Culture Techniques; D051381:Rats; D017207:Rats, Sprague-Dawley
D001786:Blood Glucose; D003470:Culture Media; D009478:Neuropeptide Y; D005947:Glucose