Effect of Amlodipine, a Calcium Channel Antagonist, on Cholesterol Levels in the Cerebral Cortex and Hippocampus OF Obese and Hypertensive SHR.Cg-Lepr super(cp)/NDmcr RATS

It has been suggested that hypertension, hyperlipidemia and diabetes participate in the onset and development of dementia. We estimated the effect of the antihypertensive drug amlodipine, a calcium channel antagonist, on blood pressure, plasma lipids and cholesterol levels in the detergent insoluble membrane fractions (DIFs) of the cerebral cortex and hippocampus in obese and hypertensive SHR.Cg-Lepr cp/NDmcr (SHR-cp) rats.Twelve male SHR-cp rats (10 weeks old) were randomly divided into two groups: a vehicle group and an amlodipine group administered amlodipine (8 mg/kg per day) orally for 9 weeks.Bodyweight did not differ between the two groups, but the level of systolic blood pressure in the amlodipine-administered SHR-cp rats was significantly lower than in the vehicle rats.The cholesterol levels of plasma and the DIFs in the cerebral cortex and hippocampus were both significantly higher in the amlodipine-administered SHR-cp rats than in the vehicle rats. Regression analysis revealed a significant positive correlation between plasma cholesterol and the cholesterol level in the DIFs of the hippocampus. These results suggest that the long-term administration of amlodipine may induce antihypertensive and hypercholesterolemic effects in obese and hypertensive SHR-cp rats.