COMPARISON OF SMOOTH MUSCLE EFFECTS OF CROTONOSIDE (ISOGUANOSINE) AND ADENOSINE

Crotonoside (isoguanosine) has been shown to be much more active than adenosine in reducing the blood pressure in rabbits and cats, in decreasing the tone of isolated intestinal strips of the rabbit, guinea pig and hamster and in stimulating the isolated uterus of guinea pigs and hamsters. The difference in activity of these two compounds is considerably more marked with the guinea pig tissues than with those of the rabbit, cat or hamster. Possible relationships to theories of action of adenosine are discussed.