CORRELATION OF LYSOSOMAL ACTIVITY AND INGESTION BY THE MANTLE EPITHELIUM ,

Abstract

Ingestion of particulate matter by the outer mantle fold of a clam, Macrocallista maculata. was studied at the light and electron microscope level. Carmine particles injected into the pallial space were localized subsequently in the epithella of the entire surface. In an attempt to identify the organelle in which the dye was localized, histochemical tests for the identification of lysosomes at the light level were carried out. Additional experiments were conducted in which colloidal gold was introduced into the pallial space. Subsequent examination of the epithelia at the E.M. level demonstrated the localization of gold particles in organeUes we ascertain to be lysosomes. The ingestion of particulate matter is initially brought about by pinocytosis. The micropinocytotic vesicles give rise to larger vesicles and eventually ingested material comes to be localized in relatively large electron dense lysosomes.