Cellular protein and mRNA expression of beta 1 nicotinic acetylcholine receptor (nAChR) subunit in brain, skeletal muscle and placenta

摘要

The in nicotinic acetylcholine receptor (nAChR) subunit is a muscle type subunit of this family and as such, is found predominantly in muscle. Recent reports document its expression in other tissues and cell lines including adrenal glands, carcinomas, lung and brain. However, the majority of studies were of tissue lysates, thus the cellular distribution was not determined. This study aimed to determine the cellular distribution of the beta 1 nAChR subunit in the brain, at both the mRNA and protein levels, using nonradioactive in situ hybridization (ISH) and immunohistochemistry (IHC), respectively, and to compare it to two muscle tissue types, skeletal and placenta. Tissue was formalin fixed and paraffin embedded (all tissue types) and frozen (placenta) from humans. Additional control tissue from the piglet and mouse brain were also studied, as was mRNA for the alpha 3 nAChR and N-methyl-D-aspartate receptor 1 (NRI) subunit. We found no beta 1 nAChR subunit mRNA expression in the human and piglet brain despite strong protein expression. Some signal was seen in the mouse brain but considered inconclusive given the probes designed were not of 100% homology to the mouse. In the skeletal muscle and placenta tissues, beta 1 nAChR subunit mRNA expression was prominent and mirrored protein expression. No alpha 3 nAChR or NR1 mRNA was seen in the skeletal muscle, as expected, although both subunit mRNA5 were present in the placenta. This study concludes that further experiments are required to conclusively state that the beta 1 nAChR subunit is expressed in the human, piglet and mouse brain. (C) 2017 ISDN. Published by Elsevier Ltd. All rights reserved.