Objective: To study roles of cholinergic M2 and M3 receptors in the motility reduction of small intestine (SI) in spleen qi deficiency. Methods: 16 male SD rats were randomly divided in the control group and spleen qi deficiency group (model group)—8 rats each group; spleen qi deficiency model of the improper diet and overfatigue was established; the SI propelling rate (SIPR) was used to evaluate the SI motility; ELISA was used to measure concentrations of acetylcholine (ACh), cyclic adenosine monophosphate (cAMP) and protein kinase A (PKA) in the SI tissue; immohistochemistry was employed to detect expressions of cholinergic M2 and M3 receptors. Results: Compared with those in the control group, SIPR was reduced; expression of M2 receptors was increased; and expression of M3 receptors and concentrations of cAMP and PKA were decreased, significantly, in the model group. Conclusions: Expression imbalance of cholinergic M2 and M3 receptors might contribute to the motility reduction of the SI in spleen qi deficiency.
References
[1]
Ganong, W.F. (2005) Review of Medical Physiology. 22nd Edition, McGraw-Hill Medical, New York.
[2]
Unno, T., Matsuyama, H. and Komori, S. (2003) Interaction between the M2and M3-Receptor Subtypes in Muscarinic Electrical and Mechanical Responses of Intestinal Smooth Muscles. Neurophysiology, 35, 262-273. http://dx.doi.org/10.1023/B:NEPH.0000008787.19396.d4
[3]
Ehlert, F.J. (2003) Pharmacological Analysis of the Contractile Role of M2 and M3 Muscarinic Receptors in Smooth Muscle. Receptors and Channels, 9, 261-277. http://dx.doi.org/10.1080/10606820308265
[4]
Matsui, M., Motomura, D., Fujikawa, T., Jiang, J., Takahashi, S., Manabe, T. and Taketo, M.M. (2002) Mice Lacking M2 and M3 Muscarinic Acetylcholine Receptors Are Devoid of Cholinergic Smooth Muscle Contractions But Still Viable. Journal of Neuroscience, 22, 10627-10632.
[5]
Haga, T. (2013) Molecular Properties of Muscarinic Acetylcholine Receptors. Proceedings of the Japan Academy. Series B, Physical and Biological Sciences, 89, 226-256. http://dx.doi.org/10.2183/pjab.89.226
[6]
Tobin, G., Giglio, D. and Lundgren, O. (2009) Muscarinic Receptor Subtypes in the Alimentary Tract. Journal of Physiology and Pharmacology, 60, 3-21.
[7]
Zholos, A.V., Tsvilovskyy, V.V. and Bolton, T.B. (2003) Muscarinic Cholinergic Excitation of Smooth Muscle: Signal Transduction and Single Cationic Channel Properties. Neurophysiolfogy, 35, 283-301. http://dx.doi.org/10.1023/B:NEPH.0000008789.82582.42
[8]
Griffin, M.T., Matsui, M., Ostromm, R.S. and Ehlert, F.J. (2009) The Guinea Pig Ileum Lacks the Direct, Highpotency, M2-Muscarinic, Contractile Mechanism Characteristic of the Mouse Ileum. Naunyn-Schmiedeberg’s Archives of Pharmacology, 380, 327-335. http://dx.doi.org/10.1007/s00210-009-0434-8
