Effect of staphylococcal α-toxin on lysosomal β-glucuronidase activity

Abstract

The effect of crude staphylococcal α-toxin (ST) on the distribution and activity of β-glucuronidase in lysosomes obtained from rat liver sucrose homogenates has been studied. The toxin caused a considerable increase of activity of β-glucuronidase of the lysosomes preincubated at 37° for 15 min. The effect has a rapid onset and is concentration dependent. The increased activity was recovered mainly in pellets although about 3–5 per cent of the total activity was found in the soluble fraction. Subsequent studies showed that ST injected i.v. caused an increase of free β-glucuronidase activity assayed in postmicrosomal fraction of rat liver homogenates. This effect could be observed whether normal, adrenalectomized or hypophysectomized rats were used. The level of total lysosomal activity of β-glucuronidase in the lysosomal fraction remained decreased even 72 hr following ST administration. Pretreatment of the rats with hydrocortisone acetate did not reduce the effect of ST. In contrast, pretreatment of rats with corticostaticum metopirone had an inhibitory effect.