Gross and microscopic characteristics of liver lesions induced by direct injection of pentobarbital sodium into rats.

Abstract

The hepatotoxic effects of anesthetics brought about by their faulty intraperitoneal application was investigated. Using a syringe with a 26G needle, we injected 0.05 ml/rat of a 50 mg/ml solution of pentobarbital sodium directly into the livers of Sprague-Dawley rats. The animals were killed at 15, 30, or 45 minutes after injection. Massive hemorrhagic necrosis of the liver was seen in all animals injected, while focal necrosis accompanied by inflammatory cell infiltration was observed in the rats killed at 30 and 45 minutes after injection. The histological characteristics of these liver lesions were composed of three types, namely, massive hemorrhagic necrosis, focal cell infiltration separate from the necrosis, and focal necrosis with inflammatory cell infiltration. The infiltrates were composed of both neutrophils and lymphocytes. The characteristic liver lesions closely resembled the hepatic lesions produced by captopril (Helliwel et al., 1985), cyclopiazonic acid (Morrissey et al., 1985), as well as spontaneous liver lesions. The study of serum transaminase levels showed that the elevation of both SGPT and SGOT activities was correlated with the time after injection. Also, a significant increase in the total bilirubin level was noted in all animals treated.