Prolonged Suppression of Irritable Aggression in Rats by Facial Anesthesia

Abstract

Local anesthesia of the mystacial epidermis with Lidocaine HCl reliably decreased shock-elicited fighting in 8 pairs of mature male Long-Evans rats. The decrease in aggressive responding was approximately twice as great as that reported for devibrissaed rats. Subsequent fighting, 3-hr. post-injection, did not differ from control or pre-injection baselines. Recording of intense vocalization accompanying fighting yielded objective data comparable to attack scores visually observed and allowed an independent measure of depressed fighting behavior. The results are discussed in reference to the import of tactual orientation for guiding directed attack and the relative merits of the technique as a vehicle for further investigation.

Vibrissal anesthesia and suppression of irritable fighting in rats: A temporary duration of effect in experienced fighters

“…The results indicate that shaving the vibrissae and local perioral anesthesia are equally effective in initially suppressing shock-elicited fighting of experienced figh t i ng p airs, confirming previous observations regarding efficacy of both techniques (Bugbee & Eichelrnan, 1972;Thor & Ghiselli , 1973b). Within three daily sessions, however, anesthesia treated experienced fighters fought at pretest baseline.…”

“…One explanation may involve a greater sensory disorientation in devibrissaed animals due to a continllous lack of sensory input from the vibrissae; in comparison, animals injected with the anesthetic were only deprived of facial sensation for a few hours each day (Thor & Ghiselli, 1973b). Another explanation may hinge on the lack of sensitivity to pain conjointly present with loss of vibrissal input in the anesthetized condition .…”

“…In view of the apparent temporary effect of vibrissal anesthesia in suppressing irritable fighting of experienced rats, the general method as originally proposed (Thor & Ghiselli, 1973a, b) has a serious limitation with inherent potential for confounding in experimental designs requiring repeated measures or sequential treatments. Detailed examination of behavior during initial exposure to footshock in the experimental context (including the presence of another rat) may suggest a more definitive analysis of the presumed interaction of prior experience with imposed deprivation of cutaneous sensation from the snout.…”

“…Anesthesia of the vibrissal pads also decreased aggressive responding to footshock (Thor & Ghiselli , 1973a, b) or to centrally induced fighting following intraperitoneal injection of apomorphine hydrochloride (Thor & Ghiselli, in press). …”

Visual, tactual, and olfactory deprivation effects on irritable fighting behavior of male hooded rats

“…Under light ether anesthesia, each subject received bilateral .2-ml subcutaneous injections of 1% lidocaine HCI (Xylocaine, Astra) with epinephrine I: 100,000 in the area of the mystacial vibrissae Y, h prior to test (Thor & Ghiselli, 1973).…”