Hydrocortisone protection of phalloidin-induced rat liver lysosome damage

Summary Phalloidin, injected i.p. at the dose of 2 mg/kg into rats, significantly reduces liver latent acid phosphatase and β-glucuronidase activity, measured 60 and 120 min after treatment. The latent/free activity ratio of both enzymatic activities is decreased, as compared to control levels. Arterial blood levels of acid phosphatase show a significant increase one hour after treatment. Phalloidin has no effect “in vitro” on lysosome-rich liver fractions at concentrations ranging from 10 −5 to 10 −4 M. Hydrocortisone treatment contemporary with Phalloidin treatment, significantly increases acid phosphataso latent activity. Lysosomal damage is postulated to play a non-secondary role in Phalloidin poisoning and the hydrocortisone protective effect to be mediated by lysosome stabilization.