Treatment of immature mice with both follicle-stimulating hormone and human chorionic gonadotrophin in vivo resulted in large increases in the specific activities of ovarian alkaline phosphatase and alkaline nucleotidase. The specific activities of other ovarian enzymes studied were not altered by gonadotrophin treatment. A simultaneous change in the Michaelis constant of ovarian alkaline phosp...

phatase may reflect enzyme contributions from bone, liver, and intestine. We have investigated serum alkaline phosphatases in two siblings with hypophosphatasia. After administration of long-chain triglycerides, the major alkaline phosphatase component of their sera was shown to be of intestinal origin on the basis of inhibition by l-phenylalanine. Starch block electrophoresis suggested that th...

Deformability of resealed erythrocyte membranes was measured by using an ektacytometer. Divalent anti-spectrin antibody, but not monovalent anti-spectrin Fab fragments, decreased membrane deformability. Membranes resealed with MgATP were more deformable than those without MgATP. Exogenous alkaline phosphatase, which dephosphorylates spectrin, decreased membrane deformability. These results sugg...