[Effects of cadralazine on the respiration, circulation, kidney, autonomic nervous system, digestive system, blood and so on].
The general pharmacological effects of cadralazine and its major metabolite ISF 2405 were studied by comparing them with those of hydralazine. Cadralazine at 3.0 mg/kg, i.v., increased respiratory movement and heart rate and decreased blood pressure in cats. Cadralazine at 3.0 mg/kg, i.v., inhibited the hypertensive response induced by adrenaline, but showed little effect on the hypotensive response induced by acetylcholine in cats. Cadralazine and ISF 2405 at 10(-4) g/ml had negative chronotropic effects on isolated guinea-pig atria. The drug at 2.5 mg/kg, p.o., inhibited the passage of BaSO4 in the gastrointestinal tract in mice. The drug at 5.0 mg/kg, i.d. or more inhibited gastric secretion in rats. Cadralazine, except at higher doses, had little effect on spontaneous gastric motility and uterine spontaneous movement in rats. Cadralazine at 2.5 mg/kg, p.o., or more reduced or tended to reduce urine volume and urinary excretion of electrolytes. The drug showed little effect on coagulation and osmotic fragility in blood cell in rats nor on hemolysis and platelet aggregation in rabbits. ISF 2405, however, showed slight or moderate influence on hemolysis at concentrations as high as 0.01-1.0%. Cadralazine at 5.0 mg/kg, p.o. or more antagonized carrageenin-induced hind paw edema in rats. In conclusion, these effects of cadralazine were found to be qualitatively identical with those of hydralazine.