Differential effects of butyrate and dibutyryl cAMP on mRNA levels of muscarinic acetylcholine receptor subtypes expressed in neurohybrid cell lines.

NCB-20 cells expressed m1- and m4-muscarinic acetylcholine receptor (mAChR) mRNAs, while NG108-15 cells expressed only m4-mAChR mRNA. Butyrate induced a time-dependent increase in the level of m1-mAChR mRNA with no change in the m4-mAChR mRNA level in NCB-20 cells. Similarly, butyrate did not affect the m4-mAChR mRNA level in NG108-15 cells. In contrast, dibutyryl cAMP caused a significant time-dependent decrease in the level of m4-mAChR mRNA in NCB-20 and NG108-15 cells as well as m1-mAChR mRNA in NCB-20 cells. Our results suggest that these two differentiating agents are important physiological regulators of the transcription and/or stability of the mRNA of certain mAChR subtypes expressed in these two neurohybrid cell lines.