The effects of unilateral carotid occlusion for one hour on cerebral blood flow were investigated in normotensive and hypotensive anaesthetized rabbits.

Cerebral blood flow was found to be 29.2+2.44 ml/100g/min. in the normotensive control group. 17.55+3.52 ml/100g/min. in the normotensive occlusion group. 24.52+2.56 ml/100g/min. in the hypotensive control group and 8.89+2.32 ml/100g/min. in the hypotensive occlusion group. It was significantly lower in the normotensive occlusion group than the normotensive control group (p <0.01). also significantly lower in the hypotensive group than all the other groups (p<0.0l). It was concluded that unilateral carotid occlusion especially when associated with hypotension brings about significant changes in cerebral blood flow.