LOCALIZATION AND DISTRIBUTION OF ALKALINE-PHOSPHATASE ACTIVITY IN THEHEPATOPANCREAS OF THE SNAIL

Histocytochemical methods were used to investigate alkaline phosphatas e activity in the digestive gland (hepatopancreas) of the common garde n snail Helix aspersa. Histochemical findings and light microscopic ob servations showed that enzymatic activity was confined mainly to the b asal connective tissue that enveloped the adenomeres. Transmission ele ctron microscopy showed that enzymatic activity was localized in the p lasma membrane, and showed an intercellular distribution along the lat eral surfaces and the basal portions of the cells in different adenome res. Alkaline phosphatase activity was also found in the plasma membra ne of fibrocytes of the basal connective tissue enveloping the adenome res. Enzymatic activity was seen around the fat droplets of glandular cells. The possible involvement of alkaline phosphatase in processes o r remodelling of the basal connective tissue that envelopes the gland is discussed.