Isoproterenol, endotoxin shock, and the generalized shwartzman reaction.

Adult hybrid albino rabbits were divided into seven groups. Three groups were given two respective intravenous doses of 10 mug, 25 mug, or 100 mug of endotoxin at an interval of 24 hours. Three other groups were given endotoxin as above, and, in addition, were given 0.5 mg of isoproterenol hydrochloride (Isuprel) by subcutaneous injections at eight-hour intervals beginning at the time of the first injection of endotoxin. A single group was given isoproterenol only. The animals were observed for clinical signs of shock beginning at the time of the first injection of endotoxin. The mortality during the course of the experiment was noted. At the time of death, the animals were studied grossly, and sections were taken for light microscopy. Results showed no meaningful enhancement of endotoxin toxicity as manifested by shock, generalized Shwartzman reaction, or mortality.

PIP: This report concerns the effects of a pure beta-adrenergic compound, isoproteronal hydrochloride, on endotoxin toxicity. 2 experimental models were used: endotoxin shock and the generalized Schwartzman reaction. 70 albino rabbits were divided into 7 groups of 10 animals and were treated as follows: Group 1, endotoxin (100 mcg) and saline; Group 2, endotoxin (100 mcg) and isoproterenol (.5 mg); Group 3, endotoxin (25 mcg) and saline; Group 4, endotoxin (25 mcg) and isoproterenol (.5mg); Group 5, endotoxin (10 mcg) and saline; Group 6, endotoxin (10 mcg) and isoproterenol (.5 mg); and Group 7, saline and isoproterenol (.5 mg). Isoproterenol was administered subcutaneously at 8-hour intervals beginning at the time of the 1st injection of endotoxin. The animals were observed for clinical signs of shock and mortality was noted. Isoproterenol treatment did not alter the mortality of endotoxin shock. At the time of death, the animals were studied grossly, and sections were taken for light microscopy. An increase in the incidence of gross renal cortical necrosis was noted only at the 100-mcg endotoxin level, where 40% of animals exhibited renal cortical necrosis compared with 10% of controls. There were no gross renal lesions in animals given isoproterenol alone. Injections of .5 mg of isoproterenol at 8-hour intervals did not alter the total number of microscopical lesions at the 3 dosage levels of endotoxin. No microscopical renal lesions were observed in those given only isoproterenol.

Morphologic alterations in sheep after implantation of the Akutsu total artificial heart.

The present report describes morphologic alterations produced in sheep after implantation of a four-chambered total artificial heart. Two groups of sheep were studied. The first group was given no special antishock therapy and had an average survival time of 25.8 hours. Major morphologic changes produced in the first group were focal infarction and massive hemorrhage of the large and small bowel, ascites, severely altered lungs and multiple infarcts in the kidneys. The second group of sheep was given antishock therapy and showed an average survival time of 35.4 hours. Severe morphologic alterations in this group were generally absent in all organs except the lungs, which showed varying degrees of congestion, hemorrhage, edema, pneumonitis and atelectasis. Death in both of the above groups was due to development of irreversible hypotension and respiratory failure.