Vasoactive intestinal polypeptide (VIP) potentiates the behavioral effect of substance P intrathecal administration.
Intrathecal (IT) injection of 20 micrograms substance P (SP) induced a behavioral syndrome consisting of scratching and biting the flanks (83% and 57%, respectively, of 48 rats), and distress-like vocalization (42% of 26 rats tested) in response to a previously innocuous tactile stimulus with a von Frey fiber (allodynia). These behavioral events following SP were of short latency (1-2 min) and duration (around 10 min). Injection IT of 5 micrograms, but not 1 microgram, of vasoactive intestinal polypeptide (VIP), concurrently with SP, significantly increased the frequency of both scratching and biting bouts over that produced by SP alone. VIP IT alone (1 or 5 micrograms) did not stimulate scratching-biting, but induced allodynia in a significant proportion of rats.
Beyer
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Institute of Animal Behavior, Rutgers University, Newark, NJ 07102.
Caba
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Banas
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Komisaruk
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D000374:Aggression / Q000187:drug effects; D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects*; D004357:Drug Synergism; D005260:Female; D007278:Injections, Spinal; D010052:Ovariectomy; D051381:Rats; D011919:Rats, Inbred Strains; D013373:Substance P / Q000008:administration & dosage / Q000494:pharmacology*; D014660:Vasoactive Intestinal Peptide / Q000494:pharmacology*; D014828:Vocalization, Animal / Q000187:drug effects
D013373:Substance P; D014660:Vasoactive Intestinal Peptide