Experimental Hypertension by Long-Term Emotional Stress and Changes of Adrenal Cortex Morphological and Morphometrical Study

Emotional stress in rats was induced by "stick-poking harassment" carried out over lengthy periods of 3 months and 1 year, and experimental hypertension was produced. Electron microscopic examination of the adrenal zona fasciculata cells in the experimental group revealed a significant enlargement of the mitochondrion and an increase in the number of lipid droplets in the 3-month group, and a significant enlargement of the mitochondrion in the 1-year group. The plasma corticosterone levels, which were measured at the same time, were significantly higher in the 3-month experimental group, but there was no significant difference noticed in the 1-year group. Corticosterone is a hy-pertensinogenic steroid, and its involvement in the hypertension was conjectured.