Hypothalamic GABA receptor functional regulation and liver cell proliferation.
GABAergic alterations in hypothalamus during compensatory hyperplasia after partial hepatectomy (PH), lead nitrate (LN) induced direct hyperplasia and N-nitrosodiethylamine (NDEA) induced neoplasia in liver were investigated. Serum GABA levels were increased in all 3 experimental groups compared with the control. GABA content decreased in hypothalamus of PH and NDEA treated rats, while it increased in LN treated rats. GABA(A) receptor number and affinity in hypothalamic membrane preparations of rats showed a significant decrease in PH and NDEA treated rats, while in LN treated rats the affinity increased without any change in the receptor number. The GABA(B) receptor number increased in PH and NDEA treated rats, while it decreased in LN treated rats. The affinity of the receptor also increased in NDEA treated rats. Plasma NE levels showed significant increase in PH and NDEA rats compared with the control while it decreased in LN treated rats. The results of the present study suggests that liver cell proliferation is influencing the hypothalamic GABAergic neurotransmission and these changes regulate the hepatic proliferation through the sympathetic stimulation.
Biju
M P
MP
Centre for Neuroscience, Department of Biotechnology, Cochin University of Science and Technology, India.
Pyroja
S
S
Rajeshkumar
N V
NV
Paulose
C S
CS
D000477:Alkylating Agents / Q000494:pharmacology; D000818:Animals; D002455:Cell Division; D002851:Chromatography, High Pressure Liquid; D004052:Diethylnitrosamine / Q000494:pharmacology; D006965:Hyperplasia / Q000139:chemically induced / Q000378:metabolism; D007031:Hypothalamus / Q000378:metabolism*; D007700:Kinetics; D007854:Lead / Q000494:pharmacology; D008099:Liver / Q000166:cytology*; D008113:Liver Neoplasms / Q000139:chemically induced / Q000378:metabolism; D008297:Male; D008934:Mitogens / Q000494:pharmacology; D009566:Nitrates / Q000494:pharmacology; D009638:Norepinephrine / Q000097:blood; D011485:Protein Binding; D051381:Rats; D017208:Rats, Wistar; D018079:Receptors, GABA / Q000378:metabolism*; D005680:gamma-Aminobutyric Acid / Q000097:blood
D000477:Alkylating Agents; D008934:Mitogens; D009566:Nitrates; D018079:Receptors, GABA; D007854:Lead; D004052:Diethylnitrosamine; D005680:gamma-Aminobutyric Acid; C017461:lead nitrate; D009638:Norepinephrine