Immune activation during mid-gestation disrupts sensorimotor gating in rat offspring.
Maternal immune activation (MIA) is a newly developed animal model of schizophrenia. It has recently been reported that when MIA is induced with the cytokine inducer polyinosinic-polycytidilic acid (poly I:C) rats do not show deficits in prepulse inhibition (PPI), a test that is often considered a validity benchmark. The aim of the current experiment was to determine whether doses of poly I:C that have previously been shown to induce the behavioural features of schizophrenia can disrupt PPI in rats. Pregnant rat dams were given a single injection of poly I:C (4.0 mg/kg) or a saline injection equivalent on gestational day 15. Acoustic startle reactivity, habituation of the startle response and PPI were assessed in juvenile (34-35 day) and adult (>56 day) offspring. Prenatal immune activation did not alter startle reactivity on startle-only or prepulse-only trials. Furthermore, there was no effect of MIA on habituation of the startle response. MIA does however disrupt PPI, as PPI was reduced significantly in adult MIA offspring, and a trend was observed in the juvenile animals. Our finding that prenatal poly I:C can disrupt PPI in MIA rats further validates this procedure as an animal model.
Wolff
Amy R
AR
Psychology Department, University of Otago, Dunedin, New Zealand.
Bilkey
David K
DK
D000161:Acoustic Stimulation / Q000379:methods; D000704:Analysis of Variance; D000818:Animals; D001522:Behavior, Animal; D005260:Female; D020233:Gait Disorders, Neurologic / Q000209:etiology*; D008297:Male; D009433:Neural Inhibition / Q000187:drug effects / Q000502:physiology; D011070:Poly I-C; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects / Q000276:immunology* / Q000503:physiopathology*; D011601:Psychophysics / Q000379:methods; D051381:Rats; D017207:Rats, Sprague-Dawley; D013216:Reflex, Startle / Q000502:physiology
D011070:Poly I-C