STUDIES ON LYSOSOMES

Abstract

Granular fractions sedimenting between 800 g and 15,000 g were prepared in 0.25 M sucrose from the livers of normal young rabbits and from the livers of rabbits injected with Aerobacter aerogenes endotoxin. As early as 5 minutes after endotoxin administration, there was an augmented release of 2 enzymes, beta glucuronidase and cathepsin, into the supernatant of fractions which had been incubated or incubated and irradiated with a mercury vapor lamp at 37[degree]C. These effects were maximum at 30 minutes after endotoxin and were associated with a depletion of the total activities of the 2 enzymes within the granules. Concurrently there was a rise in the activity of the 2 enzymes in fractions of the homogenate which were unsedimentable at 15,000 g. Fractions prepared from animals made tolerant to endotoxin no longer responded to incubation and irradiation by an augmented release of these 2 hydrolases, nor did fractions prepared from animals pretreated with glucocorticoids. Pretreatment with desoxycorticosterone acetate did not prevent release of enzymes after endotoxin.