The effects of capsaicin on emotional responses to odors in the rat.
Capsaicin is described as disturbing the autonomic responses to stress-inducing environments. The effects of capsaicin (130 mg/kg in 2 series of subcutaneous injections) on emotionality responses were studied in 19 Sprague-Dawley male rats using the open-field test. Eleven rats treated with isotonic saline served as controls. Emotionality (E) measured before capsaicin treatment in the open-field ventilated with deodorized air was similar in the 2 groups of rats. Nine out of the 19 treated rats survived. Their E was significantly higher than that of there 10 rats that died from capsaicin. When a frightening odor (fox feces) was added to the open-field E increased in the controls but remained unchanged in the capsaicin-surviving rats. The ability to discriminate palatable food or female odor was similar in the two groups. The results suggest that; 1) Highly emotional rats survived subcutaneous capsaicin injections; 2) Reaction to an emotionality-inducing environment was decreased in the capsaicin-surviving rats; 3) Olfactory discrimination was not impaired by capsaicin treatment.
Cormareche-Leydier
M
M
Physiologie neurosensorielle, CNRS Université Claude-Bernard, Lyon, Villeurbanne, France.
Vernet-Maury
E
E
D000818:Animals; D001143:Arousal / Q000187:drug effects*; D002211:Capsaicin / Q000494:pharmacology*; D004193:Discrimination Learning / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D004644:Emotions / Q000187:drug effects*; D005239:Fear / Q000187:drug effects; D007279:Injections, Subcutaneous; D008297:Male; D009812:Odorants; D051381:Rats; D011919:Rats, Inbred Strains; D012903:Smell / Q000187:drug effects*; D012931:Social Environment
D002211:Capsaicin