[Effect of repeated cooling on the state of the adrenals and corneal epithelial proliferation in white rats].

The effect of repeated cooling on the adrenal glands, on the mitosis and the number of DNA-synthesising cells in the corneal epithelium of albino rats was studied. The animals were cooled by the contact method to 28 degrees C and were exposed to this temperature for an hour daily within 5 days. Strong activation of the suprarenal glands was observed: 2-fold increase in the suprarenal weight, 3-fold decrease in cholesterol content, 4-fold growth of 11-hydroxy-corticosteroid level in the blood and enhanced adrenaline excretion. The average number of mitoses in the corneal decreases 2-fold. Depression was not associated with the change in mitosis rate but with the inhibition of the cell entrance into mitosis in interphase. The level of pathological mitoses did not change. Chronic stress was not accompanied by the change in the number of DNA-synthesising cells or intensity of DNA-symthesis.