Role of endogenous prostaglandins in excitation contraction of skeletal muscle in rats

ABSTRACT

Prostaglandins are present in every mammalian tissue. Inhibition of their synthesis by piroxicam was used as a tool to study the role of endogenous PGs in nerve excitability, neuromuscular transmission and direct muscle contraction using isolated gastrocnemius-sciatic preparations from albino rats. It was observed that inhibition of PGs synthesis by piroxicam inhibited directly as well as and to a greater extent indirectly evoked muscle contractions. It decreased peak tetanic tension and produced tetanic fade. Its inhibitory effect on indirect muscle contraction was not reversed by prostigmine. Piroxicam inhibited also acetyl choline-induced-and caffeine induced contractures. But, there was no significant effect on rheobase, utilization time and chronaxia of sciatic nerve by inhibition of PGs synthesis: