The modulation of central amygdale on cardiac nocicepption in rats / 西安交通大学学报(医学版)

ABSTRACT

Objective To study the modulation of central amygdale (CeA)on cardiac nociception with electrical stimulation in rats.Methods The heart pain model of adult male Sprague-Dawley rats was established with intrapericardial injection of capsaicin; then the evoked electromyography (EMG ) responses in the spinotrapezius (SPT)were observed as an index.Immunohistochemical method was used to observe the expression of c-fos in CeA;The rats were divided into normal control group,intrapericardial saline injection control group,and intrapericardial capsaicin injection group. The changes of EMG responses after electrical stimulation on CeA (intensity of 30μA and 70μA)were observed separately by electrophysiology in different groups.Results① Compared with normal control group, intrapericardial capsaicin injection group had significantly increased expression of c-fos in CeA.However,c-fos expression did not differ significantly between intrapericardial saline injection group and normal control group;② After 30μA electrical stimulation on CeA,EMG response in SPT significantly decreased in intrapericardial capsaicin injection group compared with that in control group;the total discharge rate was (78.58±4.62)% of that of control group (P<0.05).After 70μA electrical stimulation on CeA, the total discharge rate was (54.89±3.98)% of that of control group (P<0.05).Conclusion CeA may be involved in cardiac nociceptive transmission in rats and has inhibitory effects on the modulation of rat cardiac nociception.