Emotional stress in the development of experimental hemorrhagic stroke in rats with different levels of stress resistance

Individual behavioral characteristics in rats in an open field test characterizing their resistance to emotional stress had significant influences on the severity of neurological symptomatology in intracerebral hemorrhage. Rats predicted to be resistant to stress were characterized by faster recovery of neurological status and motor and coordination impairments by day 7 after unilateral hemorrhagic stroke in the caudate nucleus than stress-susceptible rats. Changes in vessels and neurons in the contralateral sensorimotor cortex were more marked after caudate nucleus hemorrhagic stroke in stress-susceptible animals than in stress-resistant animals, while capillary neogenesis was not seen in the former group. By day 7 of poststress hemorrhagic stroke in the caudate nucleus, stress-resistant rats, unlike stress-susceptible animals, showed compensatory mechanisms in the sensorimotor cortex contralateral to the stroke, which is evidence for the possible recovery of structures and normal neuron functioning.