[Ophthalmological study of the M-strain stroke-prone spontaneously hypertensive rats (2). Retinal arteriolar changes in fluorescein angiogram].

Malignant or precocious stroke-prone spontaneously hypertensive rats show severe hypertensive fundus changes such as generalized narrowing, caliber irregularity, and tortuosity of retinal arterioles or retinal edema. In our previous studies, these changes were classified into four grades from 0 to 3 according to severity. In the present study, hypertensive fundus changes in these rats, such as generalized narrowing or caliber irregularity of retinal arterioles, were studied by comparing fluorescein angiographs with color fundus photographs. Fluorescein leakage was observed from retinal vessels in more than half the retinal arterioles with hypertensive caliber irregularity of grade 2. Pathological studies also showed irreversible changes in the retinal arterioles with hypertensive caliber irregularity.