Increased 5-HT2C receptor binding in the brain stem and cerebral cortex during liver regeneration and hepatic neoplasia in rats.
In the present study, serotonin 2C (5-HT(2C)) receptor binding parameters in the brainstem and cerebral cortex were investigated during liver generation after partial hepatectomy (PH) and N-nitrosodiethylamine (NDEA) induced hepatic neoplasia in male Wistar rats. The serotonin content increased significantly (p<0.01) in the cerebral cortex after PH and in NDEA induced hepatic neoplasia. Brain stem serotonin content increased significantly (p<0.05) after PH and (p<0.001) in NDEA induced hepatic neoplasia. The number and affinity of the 5-HT(2C) receptors in the crude synaptic membrane preparations of the brain stem showed a significant (p<0.001) increase after PH and in NDEA induced hepatic neoplasia. The number and affinity of 5-HT(2C) receptors increased significantly (p<0.001) in NDEA induced hepatic neoplasia in the crude synaptic membrane preparations of the cerebral cortex. There was a significant (p<0.01) increase in plasma norepinephrine in PH and (p<0.001) in NDEA induced hepatic neoplasia, indicating sympathetic stimulation. Thus, our results suggest that during active hepatocyte proliferation 5-HT(2C) receptor in the brain stem and cerebral cortex are up-regulated which in turn induce hepatocyte proliferation mediated through sympathetic stimulation.
Pyroja
Sulaiman
S
Molecular Neurobiology and Cell biology Unit, Centre for Neuroscience, Department of Biotechnology, Cochin University of Science and Technology, Cochin-682 022, Kerala, India.
Joseph
Binoy
B
Paulose
Chiramadathikudiyil S
CS
D000818:Animals; D001667:Binding, Competitive; D001921:Brain / Q000378:metabolism*; D001933:Brain Stem / Q000378:metabolism; D002273:Carcinogens; D049109:Cell Proliferation; D002540:Cerebral Cortex / Q000378:metabolism; D004052:Diethylnitrosamine; D022781:Hepatocytes / Q000378:metabolism; D008099:Liver / Q000294:innervation / Q000378:metabolism*; D008114:Liver Neoplasms, Experimental / Q000139:chemically induced / Q000378:metabolism*; D008115:Liver Regeneration; D008297:Male; D009638:Norepinephrine / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D044405:Receptor, Serotonin, 5-HT2C / Q000378:metabolism*; D012701:Serotonin / Q000378:metabolism; D017779:Sympathetic Fibers, Postganglionic / Q000378:metabolism; D013570:Synaptic Membranes / Q000378:metabolism; D015854:Up-Regulation
D002273:Carcinogens; D044405:Receptor, Serotonin, 5-HT2C; D012701:Serotonin; D004052:Diethylnitrosamine; D009638:Norepinephrine