Irreversible shock in rats after injection of microspheres into the renal artery

Summary After injection of microspheres into both renal arteries of rats, an irreversible shock syndrome develops, resulting in death within 4–12 h. Ligation of both renal pedicles after injection of microspheres prevents the shock. It is presumed that kininogenases released from the kidneys participate in the pathogenesis of the shock syndrome.These studies were supported in part by the Deutsche Forschungsgemeinschaft within the SFB 90, Cardiovasculäres System.     

Sensitivity of the developing chick myocardium to the positive inotropic effects of calcium and isoproterenol

Summary The present results show that the sensitivity of the chick myocardium to the positive motropic effect of Ca⁺⁺ decreases during development and that the Ca⁺⁺ concentration of the physiological solution used must be lowered below normal to study the effects of positive inotropic agents in preparations from younger embryos. Isoproterenol elicits positive inotropic responses in 7–9-day embryonic ventricle and in newborn chick atria; however, the 4-day embryonic myocardium is unresponsive to isoproterenol.This work was supported by Grant No. HL-15995 from the National Heart Institute (USPHS).The authors would like to thank Dr.F. E. Shideman for the isolated tissue baths used in these experiments.     

The metabolism of the male antifertility agent 1-amino-3-chloropropan-2-ol in the rat

Summary The male antifertility agent 1-amino-3-chloropropan-2-ol (ACP,I) has been shown to be metabolized to-chlorohydrin (III) and metabolites of-chlorohydrin. This accounts for the similar antifertility and renal toxicity effects of both compounds.     

A cannabinoid with cardiovascular activity but no overt behavioral effects

Summary Abnormal-⁸-tetrahydrocannabidiol (ABN-⁸-THC) failed to elicit central nervous system and cardiovascular effects in laboratory animals. Abnormal-cannabidiol (ABN-CBD) was also devoid of overt behavioral effects but produced marked hypotension with only slight bradycardia in anesthesized dogs.Acknowledgment. This work was supported by NIDA (grant No. DA-00574-01 and DA-00490) and Virginia Heart Society (grant No. RR-05697)     

A centrally induced vasodepressor response after intravenous administration of whole venom ofNaja mossambica pallida in cats

Summary Naja mossambica pallida venom administered i.v. (300 /kg) produces an initial brief fall in blood pressure, due to a direct myocardial depressant effect, and a sustained fall due to central depressant effect.This study was supported by University of Nairobi research grants (670–376). We also thank Mr E. Njogu for photographic assistance.     

A tissue-selective prostaglandin E2 analog with potent antifertility effects

Summary N-methanesulfonyl 16-phenoxy--tetranor PGE₂ is a prostaglandin analog which is markedly more tissue selective than PGE₂. This compound is 10–30 times more potent than PGE₂ in animal models which are considered relevant to antifertility effects in humans. In pharmacological tests which are believed to be predictive for side effects in humans, the compound has potency either equal to or less than that of PGE₂.