Mechanism of "Xingnao Kaiqiao" acupuncture for the opening of ATP sensitive potassium channel against cerebral ischemia reperfusion injury in rats

Abstract

To observe the mechanism of "Xingnao Kaiqiao" acupuncture for the opening of ATP sensitive potassium channel (KATP) against cerebral ischemia reperfusion injury in rats. Eighty-four rats were randomly divided into a sham-operation group, a model group, an electroacupuncture (EA) group, an EA+KATP blocker group, 21 rats in each group. 10 μL intracerebral injection with glipizide (1 μmol/5 μL) was used in the EA+KATP blocker group. The cerebral ischemia reperfusion model was established by Zea Longa's suture method in the model group, the EA group and the EA+KATP blocker group. Rats in the sham-operation group were received the same surgery but without nylon filament insertion. Acupuncture (20 min a time) was performed at "Neiguan" (PC 6), "Shuigou" (GV 26) and "Sanyinjiao" (SP 6) in the EA group and the EA+KATP blocker group at 10:00 and 16:00 for 3 days, firstly 90 min after model establishment. EA (2 Hz/15 Hz, 1 mA) was connected at the affected "Neiguan" (PC 6) and "Sanyinjiao" (SP 6). The same fixation was used in the sham-operation group and the model group, without EA. Neurological function was assessed by Zausinger's neurologic assessment scale. 2, 3, 5-triphenyltetrazolium chloride (TTC) staining was used to detect infarct volume. Neurocyte apoptosis in the hippocampus was detected by flow cytometry and the protein expressions of B lymphocytoma-2 gene (Bcl-2) and B cell lymphoma factor-associated X protein (Bax) were measured by Western-blot. In comparison with the model group, the neurological score of the EA group increased (P<0.01); the infarction volume and the hippocampal neuron's total apoptosis rate of the EA group decreased (both P<0.05); the protein expression of Bcl-2 and Bcl-2/Bax of the EA group increased (P<0.05, P<0.01); and the protein expression of Bax of the EA group decreased (P<0.01). Compared with the EA group, the neurological score of the EA+KATP blocker group decreased (P<0.05); the total apoptosis rate of hippocampus neurons of the EA+KATP blocker group increased (P<0.05); the expression of Bcl-2 protein of the EA+KATP blocker group reduced (P<0.05); the expression of Bax protein of the EA+KATP blocker group increased (P<0.05). "Xingnao Kaiqiao" acupuncture has brain protective effect on rats with focal cerebral ischemia reperfusion injury. The mechanism may be related to regulating the opening of KATP channels and decreasing the apoptosis of neurons.