Prepulse startle deficit in the brown Norway rat: A potential genetic model

Prepulse inhibition (PPI), an operational measure of sensorimotor gating, i s deficient in schizophrenia patients. PPI was compared among 4 strains of mts: Sprague-Dawley, Spontaneously Hypertensive, Wistar Kyoto (WKY), and Br own Norway (BN). PPI was dramatically lower in BN versus the other strains, especially WKY, for both acoustic and airpuff startle stimuli, whereas sta rtle amplitude was similar between BN anti WKY. Female BN also had lower PP I than did female WKY. Response to increasing prepulse intensities showed a right shift in the BN relative to the WKY. Visual prepulses also showed de ficiencies in BN versus WKY. The absence of background noise did not negate strain differences. Auditory brainstem response to clicks and tone pips re vealed no differences in auditory threshold between the 2 strains. These re sults are the first to demonstrate that BN have impaired sensorimotor gatin g compared with WKY, without impaired acoustic acuity.