Microcalorimetric investigations of the metabolism of isolated human epidermis.

Microcalorimetry was used for the evaluation of metabolic and enzyme activity in human epidermis. The endogenous metabolism with a heat production Q = -2 muW/mg wet weight could be stimulated to Q = -12 muW/mg by adding glucose to the buffer. To test the enzyme activity, hydrogenation of pyruvate to lactate by lactate dehydrogenase (LDH) was chosen as an essential step of anaerobic glycolysis. The LDH activity of epidermis slices amounted to 22 mU/mg epidermis. The microcalorimetric method is discussed as a test procedure for specimens of healthy and diseased skin and for cell cultures.