Different Kinds of Acid Phosphatases in Various Cytological Structures of the Anterior Pituitary of the Guinea Pig

Abstract

INVESTIGATIONS begun by one of us¹ have been continued by further examination on the basis of Gomori's method² and its modifications³ of the acid phosphatases of the pituitary. As substrate, α- and β-glycerophosphate was used, and for reasons emphasized by Michælis⁴, the mixtures were stabilized with the acetate-veronal buffer and adjusted with a glass electrode. The sections (thickness 4 μ), first treated with citrate buffer at pH 5·5, were subjected to reaction mixtures with the following pH values: 6·8, 6·6, 6v3, 6·0, 5·5, 5·0, 4·5, 4·2, 4·1, 4·0, 3·9 and 3·5. In critical ranges the intervals were made shorter. The incubation times were 30 min., 1 hr., 2 hr., 24 hr., 48 hr. and 72 hr. Eighteen pituitaries of female and male guinea pigs were investigated. The process of diffusion as a possible source of errors was observed to be smaller than in the case of alkaline phosphatase. Some inconstancy of reaction already noticed and discussed by several previous authors⁶ did not interfere with the principal differences of localization and relative amounts of enzymes at various pH.