Effects of phencyclidine on prepulse inhibition of acoustic startle response in the macaque.
BACKGROUND
Prepulse inhibition (PPI) of the acoustic startle response (ASR) provides an index of neurophysiological dysfunction in schizophrenia and a method for analyzing underlying neurochemical mechanisms. In rodents, phencyclidine (PCP) and other N-methyl-D-aspartate receptor (NMDAR) antagonists induce schizophrenia-like PPI deficits. Similar effects have recently been observed in a New World monkey species, Cebus apella.


OBJECTIVE
The present study evaluates the degree to which similar effects are observed in an Old World monkey, M. fascicularis.


METHODS
An initial study evaluated effects of interstimulus interval on PPI amplitude and latency. A subsequent study evaluated effects of PCP (0.25 mg/kg i.m.) on PPI of the ASR.


RESULTS
Prepulses reduced both the amplitude and latency of the ASR. PCP treatment prevented both effects without affecting amplitude or latency of the ASR itself.


CONCLUSIONS
These results demonstrate that both amplitude reduction and latency facilitation are observed during PPI in the monkey and are disrupted by PCP.
Javitt
D C
DC
Program in Cognitive Neuroscience and Schizophrenia, Nathan Kline Institute, Orangeburg, NY 10962, USA. javitt@nki.rfmh.org
Lindsley
R W
RW
D000161:Acoustic Stimulation; D000818:Animals; D004576:Electromyography; D005071:Evoked Potentials / Q000187:drug effects; D006213:Hallucinogens / Q000494:pharmacology*; D008252:Macaca fascicularis; D010622:Phencyclidine / Q000494:pharmacology*; D016194:Receptors, N-Methyl-D-Aspartate / Q000037:antagonists & inhibitors; D013216:Reflex, Startle / Q000187:drug effects*
D006213:Hallucinogens; D016194:Receptors, N-Methyl-D-Aspartate; D010622:Phencyclidine