Acute treatment of hypertension increases infarct sizes in spontaneously hypertensive rats

We studied the effect of dihydralazine treatment of hypertension in spontan eously hypertensive stroke-prone rats in a model of permanent focal cerebra l ischemia (stroke). After occlusion of the middle cerebral artery systemic arterial pressure (SAP) was lowered with a computer controlled infusion de vice from 163 to 135 or 117 mmHg for 24 h. In the control group SAP was not manipulated. Reduction of SAP to normotension (117 mmHg) significantly wor sened outcome and increased infarct volume measured 7 days after induction of ischemia, whereas a mild reduction of SAP (to 137 mmHg) had no statistic ally significant effect on outcome or infarct volume. We conclude that phar macological treatment of hypertension may negatively affect neurological ou tcome and infarct volume in a rat stroke model. NeuroReport 11:355-359 (C) 2000 Lippincott Williams & Wilkins.