Neonatal capsaicin exposure affects isolation-induced aggressive behavior and hypothalamic substance P levels of adult male mice (Mus musculus).

S Bigi; L De Acetis; R De Simone; L Aloe; E Alleva

doi:10.1037//0735-7044.107.2.363

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Neonatal capsaicin exposure affects isolation-induced aggressive behavior and hypothalamic substance P levels of adult male mice (Mus musculus).

S Bigi·L De Acetis·R De Simone·L Aloe·E Alleva

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Abstract

Subcutaneous administration of capsaicin (50 mg/kg) at Postnatal Days 2 and 5 exerted long-term effects on isolation-induced aggressive behavior of adult mice (Mus musculus) of the CD-1 strain. Isolated capsaicin-treated mice (scored during a 10-min session) showed the highest frequency and the longest duration of total attacks, attacks, rattling, and offensive upright posture when compared with nonisolated capsaicin-treated subjects and both isolated and nonisolated vehicle control animals. Hypothalamic Substance P (SP) was assessed by radioimmunoassay. Capsaicin treatment significantly lowered hypothalamic SP content in both isolated and nonisolated mice. Moreover, individual scores of isolated capsaicin-treated subjects showed a significant correlation between SP depletion and expression of offensive upright posture. Isolation per se was revealed to play an important role in depleting SP from the hypothalamus.

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Aggression Agonistic Behavior Animals Animals, Newborn Capsaicin Hypothalamus Injections, Subcutaneous Male Mice Nociceptors Pain Threshold Social Isolation Substance P Thermosensing Journal Article Research Support, Non-U.S. Gov't

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S Bigi, L De Acetis, R De Simone, L Aloe, E Alleva. 1993. Neonatal capsaicin exposure affects isolation-induced aggressive behavior and hypothalamic substance P levels of adult male mice (Mus musculus).. https://doi.org/10.1037/%2F0735-7044.107.2.363

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