title: Microinjections of D-Ala2-Met5-enkephalinamide placed into nucleus accumbens suppress hypothalamically elicited hissing in the cat.
abstract: The effects of D-Ala2-Met5-enkephalinamide (DAME) upon the hissing component of hypothalamically elicited affective defense behavior in the cat were examined in this study. Microinjections of DAME placed into the nucleus accumbens significantly suppressed this response in a dose and time dependent manner. This dose dependent suppression of affective defense decreased toward baseline levels at 60 and 90 min following delivery of 1 and 10 micrograms/0.5 microliters of DAME, respectively. Similar injections placed into the caudate nucleus had no effects upon this response. Neither vehicle control nor naloxone placed into nucleus accumbens was found to significantly alter latencies for hissing. Naloxone injected into nucleus accumbens prior to administration of either a 1-microgram or a 10-micrograms dose of DAME blocked the suppressive effects of DAME that were observed when this drug was administered alone. These findings suggest that opioid receptors in the nucleus accumbens play an important role in the regulation of the hissing component of hypothalamically elicited affective defense behavior in the cat.
authors.affiliation: Department of Neuroscience, UMDNJ--New Jersey Medical School, Newark 07103.
authors.forename: M
authors.initials: M
authors.lastname: Brutus
authors.forename: S
authors.initials: S
authors.lastname: Zuabi
authors.forename: A
authors.initials: A
authors.lastname: Siegel
mesh_terms: D000374:Aggression / Q000187:drug effects*; D000818:Animals; D002415:Cats; D002421:Caudate Nucleus / Q000187:drug effects / Q000502:physiology; D004744:Enkephalin, Methionine / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000494:pharmacology; D005260:Female; D007031:Hypothalamus / Q000187:drug effects / Q000502:physiology*; D008297:Male; D008845:Microinjections; D009270:Naloxone / Q000494:pharmacology; D009714:Nucleus Accumbens / Q000187:drug effects / Q000502:physiology*; D012016:Reference Values; D012686:Septal Nuclei / Q000502:physiology*; D013997:Time Factors; D014828:Vocalization, Animal
chemical_list: D009270:Naloxone; D004744:Enkephalin, Methionine; C022118:enkephalinamide-Met, Ala(2)-