Studies on curariform activity of hayatinin methochloride, an alkaloid of Cissampelos pareira.

Experiments were carried out on the isolated phrenic nerve diaphragm preparation of the rat and isolated sartorius nerve muscle preparations of the frog (Rana tigrina), for the comparison of the neuro-muscular blocking activity. The preparations were set up in 100 ml organ bath containing Tyrode solution at 37°C for rat diaphragm and at room temperature for the frog muscle preparation. The solution was bubbled with a mixture of 5 % carbon dioxide and 95% oxygen. The nerve was sucked into a capillary electrode in the bath (4) and stimulated supramaximally through an electronic stimulator with