Social approach to pain in laboratory mice.
It has been recently demonstrated that pain behavior in the mouse can be modulated by the presence of a conspecific, but what remains unclear is whether such pain behavior can serve the function of soliciting social approach. Using a novel social approach paradigm, we tested mice in various dyadic or triadic conditions, including "jailed" mice-some in pain via intraperitoneal injection of 0.9% acetic acid-and test mice free to approach or avoid the jailed mice. We observed a sex-specific effect whereby female, but not male, test mice approached a familiar same-sex conspecific in pain more frequently than an unaffected familiar or unfamiliar, but affected, conspecific. Despite a substantial literature emphasizing oxytocin's role in affiliative and pair-bonding behavior, this effect was also observed in female mice lacking the oxytocin receptor, suggesting that pain-related social approach may not be mediated by oxytocin. Furthermore, we found that the frequency of contact by the test mouse was negatively correlated with the pain behavior of the jailed mouse, suggesting that proximity of a familiar unaffected conspecific may have analgesic properties.
McGill University, Montreal, Quebec, Canada.
Dale J
DJ
Langford
Alexander H
AH
Tuttle
Kara
K
Brown
Sonya
S
Deschenes
David B
DB
Fischer
Amelia
A
Mutso
Kathleen C
KC
Root
Susana G
SG
Sotocinal
Matthew A
MA
Stern
Jeffrey S
JS
Mogil
Wendy F
WF
Sternberg
D019342:Acetic Acid / Q000009:adverse effects; D000704:Analysis of Variance; D000818:Animals; D003250:Constriction; D004195:Disease Models, Animal; D005260:Female; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D010146:Pain / Q000139:chemically induced / Q000503:physiopathology* / Q000523:psychology*; D018045:Receptors, Oxytocin / Q000172:deficiency; D012737:Sex Factors; D012919:Social Behavior; D012938:Social Perception
D018045:Receptors, Oxytocin; D019342:Acetic Acid