The Effect of Lovastatin on the Electrophysiological Properties of CA1 Pyramidal Neurons in a Rat Model of Alzheimer Disease

Background: Statins are widely used to control the level of plasma cholesterol. There is growing evidence that statins reduce the prevalence of Alzheimer disease (AD) and dementia. Objectives: The present study evaluated the effect of lovastatin treatment on neuronal responses of pyramidal cells of the CA1 region of the hippocampus in a rat model of AD. Methods: Rats randomly separated into 4 groups (n = 10): the lesion group of nucleus basalis magnocellularis (NBM) that received destruction by an electrical method (0.5 mA, 3 seconds) and lovastatin groups [lesion + lovastatin (10, 20, and 30 mg/kg)]. An in vivo single-unit recording method was used in rats anesthetized with urethane. After 15 minutes of baseline recording from pyramidal neurons in the CA1 region of the hippocampus, intraperitoneal injections of lovastatin and dimethyl sulfoxide (DMSO) were administered, and neuronal response to administration of lovastatin continued to be recorded for 105 minutes. Results: Acute injection of 30-mg/kg lovastatin excited 11 out of 17 neurons and inhibited 2 neurons. On the other hand, intraperitoneal injection of lovastatin in the highest dose resulted in increased spontaneous activity in the CA1 region of the hippocampus. Conclusions: The acute use of lovastatin increases the neuronal frequency in the pyramidal neurons of the CA1 region of the hippocampus.