Empathy is crucial for communication and survival for individuals. Whether empathy in pain contagion shows sex differences and its underlying mechanisms remain unclear. Here, we report that pain contagion can occur in stranger female rats, but not in stranger males. Blocking oxytocin receptors in the anterior cingulate cortex (ACC) suppressed pain contagion in female strangers, while oxytocin administration induced pain contagion in male strangers. In vitro, corticosterone reduces neuronal activation by oxytocin. During male stranger interactions, higher corticosterone decreased oxytocin receptor-positive neuronal activity in the ACC, suppressing pain contagion. These findings highlight the role of oxytocin in pain contagion and suggest that sex differences in empathy may be determined by the balance of oxytocin and corticosterone in the ACC. This study suggests an approach for the treatment of certain mental disorders associated with abnormal empathy, such as autism and depression.
Animals ; Oxytocin/pharmacology* ; Gyrus Cinguli/drug effects* ; Male ; Female ; Corticosterone/pharmacology* ; Empathy/drug effects* ; Sex Characteristics ; Receptors, Oxytocin/antagonists & inhibitors* ; Pain/psychology* ; Rats ; Rats, Sprague-Dawley ; Neurons/metabolism*

Objective To investigate the traditional Chinese medicine(TCM) syndromes distribution rule of nonalcoholic fatty liver disease(NAFLD) and its correlation with related clinical indexes.Methods The general condition,TCM four diagnostic methods,biochemical and CT results in 1950 cases of NAFLD in Chongqing City were investigated for analyzing the TCM syndromes distribution rule and its correlation with biochemistry and CT.Results In 1950 cases,the accumulation and binding of damp-heat,congestion of dampness turbidity,stagnation of liver-QI with spleen deficiency,intermin-gled phlegm and blood stasis and yin deficiency of both liver and kidney accounted for 36.62 ％,27.69 ％,19.38 ％,10.10 ％ and 6.21 ％ respectively;there was statistically significant difference in age among different TCM syndromes(P＜0.05);the vin deficiency syndrome of both liver and kidney and intermin-gled phlegm and blood stasis in severe fatty liver were maximal;glutamic-pyruvic transaminase(ALT) and glutamic-oxalacetic transaminase(AST) level was higher in the accumulation and binding of damp-heat;the level of fasting plasma gluco se(FBG) was higher in the yin deficiency syndrome of both liver and kidney;the total cholesterol(TC),triglyceride(TG) and FBG levels were lower in the stagnation of liver-QI with spleen deficiency,the differences were statistically significant(P＜0.05).Conclusion In NAFLD patients,the accumulation and binding of damp-heat distribution is maximal,the proportion of severe fatty liver with vin deficiency syndrome of both liver and kidney is higher.Different dialectical types may play an important role in the clinical indexes and disease development.