Analysis of the Time Course of Action of Drugs on Smooth Muscle
Although the time course of action of a drug constitutes one of its main pharmacological characteristics, the kinetic aspects are difficult to analyze. Clark (1931), in his classic work, gives a general discussion of the results of empirical approaches. By these some regularities have been found, expressed, for example, in hyperbolic relationships of the type C n t = k, where C is the concentration of drug, t the time to reach some defined end point; the value of n varies according to the system studied. But such a function has limited theoretical use. The following discussion explores how more recent studies of receptor properties can be exploited.
KeywordsSmooth Muscle Partial Agonist Receptor Occupancy Dose Ratio Intestinal Smooth Muscle
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- Ariens, E. J. 1964. Molecular Pharmacology. Academic Press, New York and London.Google Scholar
- Bolton, T. B. 1971. Electrophysiological evidence of an electrogenic sodium pump in the longitudinal muscle of guinea-pig ileum and its involvement in the response to acetylcholine. J. Physiol, 218:58–59P.Google Scholar
- Clark, A. J. 1931. General pharmacology. In: Heffters Handbuch d. Exp. Pharmakol., Vol. 4, pp. 1–228.Google Scholar
- Colquhoun, D. 1973. The relation between classical and cooperative models for drug action. In Drug Receptors, pp. 149–182. Ed. by Rang, H. P. Macmillan, London. (Biol. Council Symposium).Google Scholar
- Flacke, W. and Yeoh, T. S. 1968. Differentiation of acetylcholine and succinylchoHne receptors in leech. Br. J. Pharmacol., 33:154–161.Google Scholar
- Paton, W. D. M. and Rothschild, A. M. 1965. The change in response and in ionic content of smooth muscle produced by acetylcholine action and by calcium deficiency. Br. J. Pharmacol., 24:437–448.Google Scholar
- Rang, H. P. and Ritter, J. M. 1969. A new kind of drug antagonism: evidence that agonists cause a molecular change in acetylchohne receptors. Mol. Pharmacol., 5:384–411.Google Scholar
- Stephenson, R. P. 1956. A modification of receptor theory. Br. J. Pharmacol., 11:379–393.Google Scholar