The role of linoleic acid in hypoxia-induced changes of the action potentials and the force of contraction of isolated papillary muscles of the guinea pig.

With sufficient oxygen supply to isolated papillary muscles of the guinea pig no specific effect of linoleic acid on the parameters of muscle function could be detected. During hypoxia, however, there was a marked reduction in effective refractory period and in contractile force which had the same order of magnitude in substrate-free and in linoleic acid-containing medium. With glucose in addition to linoleic acid, the shortening in refractory period could be delayed, although no influence on the impairment of force of contraction was observed. Conversely, the decrease in both action potential duration and force of contraction could be delayed considerably in hypoxic perfusion media containing increasing concentrations of glucose.