Aspirin Enhance The Expression Of UCP4 And ATPase6 In Ischemia/Reperfusion In Rats

Background and purpose: After Ischemia/Reperfusion, damnification of the neuronal cell has two forms necrosis and apoptotic. As the"energy center"of the cell, the mitochondrial play the important role in the two forms. Recently, we distinguish that UCP4 is a kinds of transporters located in the inner membrane of mitochondrion. Actived UCP4 can dissociate oxidative phosphorylation from respiration. UCP4 can protect the neuronal cell by regulating the mitochondrion membrane potential, maintaining the Ca2+ homeostasis, reducing oxidative stress,influencing the ATP production, regulating the energy of cell. ATPase6 is also a transporters presented in the inner membrane of mitochondrion. It is a important part of F0-F1-ATP synthase and the progress of ATP production. In addition, as a hydronium pump, ATPase6 can keep the hydronium balance of the two sides of memdrane, maintain the memdrane′s function, benefit the energy metabolize. The change of ATPase6 must influence the produce, and than relate the survival or death of the cell. So the expression of the ATPase6 can reflect the ATP level. Aspirin (ASA) is a classical non-steroidal anti- inflammatory drug. Recently researches discovered that ASA also had the direct neuroprotective effects, such as increase of the ATP output; suppression of the glutamic acid release, reform of the energy metabolize of cerebra; decrease of Inos expression, and increase of the nNOS expression; inhibition of NF-κB activation; elimination of the ROS; activation of cdk5/P53; inhibition hydronium pore, prevention of Zn2+ inflow; inhibition of Fasl and caspase-3 in apoptotic, enhancement the expression of Bcl-2/bax; increase the BDNF, NGF, bFGF; decrease inflammation. So the main intention of this study is to clearing the expression rule of UCP4 and ATPase6 after CI/RP in rats, and the neuroprotective mechanism of ASA, how ASA effect the expression of UCP4 and ATPase6.Methods: The rat model of MCA-CI/RP were established with suture occlusion technique according to modified Zea Longa method and the rats of 1-3 score(Bederson measuring scale) was selected into the 10 groups at 6 hours after CI/RP. Some cerebral slices were taken for TTC staining. The rats were divided into five groups according to the time of reperfusion in control groups: A(0h), B(6h), C(24h), D(48h) and E(72h), so did the experimental groups (A'～E'). ASA were given to the experimental groups with the dose of 80mg/kg via an i.p. route, while the same dose of diaminocaproic acid were given to the control groups after the CI/RP and the next three days till killed at assigned time. The neurologic detect scale were used by Bederson scores. The UCP4 and ATPase6 expression were detected by immunohistochemistry and immunofluorescence technique.Results: Comparing with the control groups, the Bederson measuring scale of experiment groups were conspicuously reduced, but only at 72 hours after CI/RP had statistical significance(P<0.05). The positive UCP4 and ATPase6 could be seen in the cytoplasm in cortex broadly. In the control groups, the expression of UCP4 reached to peak at 6 hours after CI/RP, and descended gradually later; but had two peaks at 6 hours and 48 hours in experiment groups. ATPase6 declined evidently in both control and experiment groups and significance at 24 hours (P<0.01). It is no evidence that ASA can effect on UCP4 and ATPase6 in no-ischemia cerebra.Conclusion: 1. Ischemia can induce UCP4 expression in neurons overlying in the infarct region after CI/RP and the expression has a peak at 6 hours. 2. ATPase6 expresses descendant and significance at 24 hours after CI/RP. 3. ASA can enhance the expression of UCP4 and ATPase6 in ischemia cerebra and have no influence in no- ischemia cerebra. The expression of UCP4 has 6 hours and 48 hours two peaks. 4. ASA may attenuate the neurologic impairment after CI/RP. The mechanism of neuroprotective effect of ASA maybe due to enhance the expression of UCP4 and ATPase6, decrease the produce of ROS, maintaining the Ca2+ homeostasis and advance the ATP level relatively.