Microinfarction as a result of hypertension in a primate model of cerebrovascular disease

Ten adult cynomolgus monkeys were studied as a non-human primate model of h ypertensive cerebrovascular disease. Seven were made hypertensive by surgic al coarctation of the aorta and three served as unoperated controls. After survival periods of 8-30 months, the brains were serially sectioned and sur veyed for neuropathological changes. The most conspicuous change was minute areas of microinfarction in the white and gray matter. The lesions were of irregular shape with an average maximum diameter of less than 0.5 mm. They were slightly larger in the gray than in the white matter and appeared to be of different ages. Their area of predilection was the white matter of th e forebrain, with smaller numbers in the cerebral cortex and scattered lesi ons elsewhere in the forebrain, brain stem and cerebellum. These microinfar cts did not correspond to usually described lesions in the human brain in h ypertension or in other animal models of hypertensive cerebrovascular disea se. We suggest that they rep resent an early change in the natural history of hypertensive neuropathology.