Effects of rate and rhythm on contraction of rat papillary muscle.
نویسندگان
چکیده
HOFFMAN, BRIAN F. AND JOHN J. KELLY, JR. Efects of rate and rhythm on contraction of rat papillary musch~. Am. J. Ph ysiol. Ig7(6): 1 Igg-1204. 1959. -The unusual relationship between frequency of contraction and tension developed by the isolated rat papillary muscle has been studied in detail. The progressive decrease in tension with increasing rate is unrelated to the size or weight of the muscle and is not changed by alterations in the ionic composition of the perfusion medium. The forcefrequency relationship is also unchanged by addition of plasma, epinephrine or digitalis to the perfusion medium. Rat papillary muscle is similar to other preparations of cardiac muscle with respect to recovery of contractility and the development of rest contractions and postextrasystolic potentiation.
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ورودعنوان ژورنال:
- The American journal of physiology
دوره 197 شماره
صفحات -
تاریخ انتشار 1959