Expression and Function Analysis of Cholinergic Components nAChRα7 in Preadipocytes / 中国生物化学与分子生物学报

ABSTRACT

The non-neuronal cholinergic system, widely exists in prokaryotic, eukarytic, and even plant cells, however, it has not been investigated in preadipocytes and adipocytes. To search for evidence its existence in preadipocytes and adipocytes, the nicotinic acetylcholine receptor (nAChR) α7 subunit, acetyicholinesterase (ACHE) and choline acetyltransferase (CHAT) in 3T3-L1 cells were examined using immunohistochemical staining and Western blotting. The choline-regulated visfatin expression in 3T3-L1 preadipocytes was also tested by reverse transcriptase-PCR. Incubation with methyilycaconitine (10-6 to 10-4mol/L) for 12, 24 and 36 hours dose-dependently increased visfatin expression from 1.3- to 1.55-folds (P <0.01) with maximal induction at 24 hours with 10-4mol/L methyllycaconitine. Nicotine treatments (10-6 to 10-4 mol/L) for 12, 24 and 36 hours decreased visfatin expression; choline chloride (10-4 mol/L))suppressed visfatin expression in 3T3-L1 preadipocytes at 36 hours by 1.64 to 2.03 fold (P < 0.05) which was more effective as compared with nicotine. It was concluded that α7 nAChR was expressed in 3T3-L1 preadipocytes and involved in visfatin expression.