MIDGUT EPITHELIUM OF AMERICAN COCKROACH - ACID PHOSPHOMONOESTERASE ACTIVITY DURING FORMATION OF AUTOPHAGIC VACUOLES

Ultrastructural examination of the midgut epithelium of Periplaneta americana (L.) has shown that starvation causes a cyclic change in the number of autophagic vacuoles. A peak in number of vacuoles occurs 4 days after starvation is initiated. Correlated with these changes is a rise and fall of acid phosphatase activity with a peak identical to that of the vacuoles on day 4. Histochemical localization of the enzymatic activity within the vacuoles suggest that they are autophagic in nature. The midgut acid phosphatase has been partially purified and characterized. © 1968.