Electron microscopic cytochemistry for demonstration of sodium fluoride sensitive adenyl cyclase in normal human epidermis.

Adenyl cyclase activity in normal human epidermis was detected by an electron microscopic cytochemical technique. The sodium fluoride sensitive receptors were demonstrated on the outer sheath of the cell membranes. Adenyl cyclase activity was demonstrated in the basal cells and in the 4-5 lower layers of the Malpighian cells, while the superficial layers, stratum granulosum and stratum corneum showed no activity. The findings confirm and extend previous biochemical studies and provide a clue to the conception of the adenyl cyclase enzyme as a transmembrane arranged system.