[CGRP may take part in the effect of electroacupuncture in resisting acute myocardial ischemic injury].

ABSTRACT

OBJECTIVE: To probe into the relationship between "Xinshu" (BL 15)-"Jueyinshu" (BL 14) of the Bladder Channel and the heart and the underlying mechanism of electroacupuncture (EA) in resisting acute myocardial ischemia (AMI) in rats. METHODS: A total of 24 male Wistar rats were randomly divided into control, model and EA groups with 8 cases in each group. AMI model was duplicated by intraperitoneal injection of 2% isoproterenol (ISO, 100 mg/kg). EA (pulse duration 300 micros, frequency 2-20 Hz, output voltage 3. 5-5 V) was applied to BL14 and BL15 on the left side for 30 min, twice in a day (with an interval of 12 h). After decapitation, blood samples, myocardial tissue and spinal cord (T1-T6) were collected respectively for detecting serum creatine kinase (CK, with chromatometry) and calcitonin gene-related peptide (CGRP) contents in the plasma, myocardium and the spinal cord (with radioimmunoassay). RESULTS: In comparison with control group, serum CK of both model group and EA group increased significantly (P < 0. 01), and plasma CGRP content of model group lowered lightly; while compared with model group, CK content of EA group decreased obviously (P < 0.05) and plasma CGRP of EA group increased evidently (P < 0.05). No significant differences were found among 3 groups in myocardial CGRP contents and between control group and model group in spinal CGRP contents (P > 0.05). CONCLUSION: EA of "Xinshu" (BL 15)-"Jueyinshu" (BL 14) may suppress isoproterenol-injection induced myocardial injury and plasma CGRP possibly takes part in the protective effect of EA in resisting myocardial ischemia injury.