Expression of non-neuronal cholinergic system in maxilla of rat in vivo

BACKGROUND: Acetylcholine (ACh) is known to be a key neurotransmitter in the central and peripheral nervous systems, which is also produced in a variety of non-neuronal tissues and cell. The existence of ACh in maxilla in vivo and potential regulation role for osteogenesis need further study. RESULTS: Components of the cholinergic system (ACh, esterase, choline acetyltransferase, high-affinity choline uptake, n- and mAChRs) were determined in maxilla of rat in vivo, by means of Real-Time PCR and immunohistochemistry. Results showed RNA for CarAT, carnitine/acylcarnitine translocase member 20 (Slc25a20), VAChT, OCTN2, OCT1, OCT3, organic cation transporter member 4 (Slc22a4), AChE, BChE, nAChR subunits α1, α2, α3, α5, α7, α10, ß1, ß2, ß4, γ and mAChR subunits M1, M2, M3, M4, M5 were detected in rat's maxilla. RNA of VAChT, AChE, nAChR subunits α2, ß1, ß4 and mAChR subunits M4 had abundant expression (2(-ΔCt) > 0.03). Immunohistochemical staining was conducted for ACh, VAChT, nAChRα7 and AChE. ACh was expressed in mesenchymal cells, chondroblast, bone and cartilage matrix and bone marrow cells, The VAChT expression was very extensively while ACh receptor α7 was strongly expressed in newly formed bone matrix of endochondral and bone marrow ossification, AchE was found only in mesenchymal stem cells, cartilage and bone marrow cells. CONCLUSIONS: ACh might exert its effect on the endochondral and bone marrow ossification, and bone matrix mineralization in maxilla.

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

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.

Sequence analysis of muscarinic receptors M1, M3 and M5 expression by cultured rat astrocyte cells / 中国药理学通报

Aim To clone the muscarinic receptors M1, M3 and M5 sequences of astrocyte cells,and compare the gene and protein sequences with those of neurons. Methods Specific primers were designed to clone the M1, M3 and M5 sequences of astrocyte cells by RT-PCR according to those of neurons,then sequenced the sequences. Result By comparing the M1, M3 and M5 sequences expression by astrocyte cells with those by neurons and we found four, eight,and one different bases and one, four and one different amino acids in M1, M3 and M5 between astrocyte cells and neurons respectively. Conclusions The gene and protein sequence differences are evident in M1, M3 and M5 between astrocyte cells and neurons.