Symptomatological classification in the development of stroke in stroke-prone spontaneously hypertensive rats.

The developmental course of cerebrovascular diseases was examined by comparative neurological and pathological studies in stroke-prone SHR (SHRSP) which died spontaneously or were sacrificed. Behavioral status during their life span could be simply divided into 4 patterns, i.e., "no abnormalities", "irritable", "lethergic" and "akinetic" named Grades 0, I, II and III, respectively (Yamori's Classification). Grades I, II and III of behavioral status corresponded well to symptomato-pathoanatomically divided 3 stages (relating to brain edema), i.e., Stages I, II and III, respectively.