AIM: To study the protecitve mechanism of Ligustrazine (LT), Shenmai Parenteral Injection (SPI), combination of Ligustrazine and Shenmai Parenteral Injection (LSP) to myocardial injury after brain ischemia-reperfusion in aged rats from the change in ATPase and free radical in order to provide theoretical basic for prevention and cure of cerebral infarction. METHODS: Aged rats (more than 20 months) were divided into model group, control group, Nimotop group, LT group, SPI group and LSP group. We measured the following items in aged rats with 60 min of reperfusion after 30 min of brain ischemia: the content of MDA, the activities of superoxide dismutase (SOD), lactic dehydrrogenase (LDH), creatine phosphokinase (CPK), ATPase. RESUTLS: The CPK and LDH activities in the model rats increased obviously. The serum CPK activity in the LSP group, the LT group, nimotop group was lower than those in the model group obviously. The serum LDH activities in LT group and SPI group were obviously lower compared with those in the model group. The activity of Na＋-K＋-ATPase and Ca2＋-ATPase in model group was decreased. Contrast to the model group, the activity of Na＋-K＋-ATPase in LSP group, Nimotop group, LT group and the activities of Ca2＋-ATPase in the LSP group were higher. The serum MDA/SOD ratio was larger than that in the control group. The decrease in myocardial SOD activity and the increase in the MDA level, MDA/SOD ratio in the model group showed significant difference compared with that in the control. The MDA level in the LSP group was lower than that in the model group. The increase in myocardial SOD activity and decrease in MDA, MDA/SOD ratio were obvious in the LSP group compared with the model group. CONCLUSION: The myocardial injury after brain ischemia-reperfusion in aged rats was related to the decrease in the activity of Na＋-K+-ATPase and injury of free radical. LT, SPI, LSP and Nimotop could prevent this inury. Nimotop and LT could enhanced the activity of Na+-K+-ATPase obviously. SPI could enhance the activity of Ca2＋-ATPase and restrain the injury of free redical and lipid peroxidation. This may be the mechanism of restraining myocardial injury after brain ischemia-reperfusion.

Bradykinin (BK) is a calcium/calmodulin dependent protein kinase Ⅱ (CaMKⅡ) specific activator, and Cyclosporin A (CSA) is reported to suppress protein phosphotase (PP)-2B activity. In vitro studies have shown that CaMKⅡ and PP-2B play an important role in Alzheimer-like phosphorylation of microtube-associated protein tau. To reconstitute an animal model based on the imbalance of protein kinase (s) and protein phosphatase (s) seen in Alzheimer brain, we injected BK and/or CSA into rat hippocampus. The results from behavioral study showed that an obvious disturbance in learning and memory was seen with BK or BK plus CSA injected rats. Moreover, the behavior abnormality appeared earlier in aged rats than young adults of the same kind after the injection. On the other hand, no obvious dysfunction in living and behavior was observed with CSA alone injected rats. The results obtained by immunohistochemical assay indicated that the staining for M4\, 12E8\, PHF-1 and CaMKⅡ was stronger, and for Tau-1 was weaker in BK injected rats compared with Control group. It was also found that the binding of M4 and PHF-1 but not 12E8 to tau was significantly increased in CSA injected rats. As the same as BK injection, binding of Tau-1 to tau was decreased after CSA injection. The immunostaining for 12E8\,PHF-1 and CaMKⅡ was increased, whereas for Tau-1\, M4\, and GSK-3 was decreased after combination injection of BK and CSA. In addition, the staining of PP-2B decreased in all the three models. To our knowledge, this is the first data shown in vivo that the activation of CaMKⅡ induces both Alzheimer-like tau phosphorylation and behavioral disturbance.

AIM: To study the mechanism of myocardial injury after brain ischemia-reperfusion in aged rats from the changes in Dopamine (DA), Noradrenalin (NE), Epinephrine(E) and Neuropeptide Y(NPY).METHODS: Young (5 months) and aged (20 months or more) rats were divided into model groups and normal control groups, respectively. We observed the following items in rats with 60 minute reperfusion after 30 minute brain ischemia: the pathological changed of myocardium, the activities of lactic dehydrrogenase(LDH), creatine phosphokinase(CPK), the contents of NE, DA, E, NPY. RESULTS:The CPK and LDH activities in the young model rats were higher than those in the young control rats was higher than that in the young control rats (P＜0.05). The serum CPK activity in the aged control rats was higher than that in the young control rats (P＜0.05). The myocardial CPK activity was higher in the aged model rats compared with the young molel rats (P＜0.05) and was higher in aged control rats compared with the young control rats (P＜0.01). The myocardial LDH activity was lower in the aged control rats than that in the young control rats (P＜0.05) and aged model rats (P＜0.01). The serum NE level, the level of NE and DA in the hypothalamus were higher obviously than those in the young control rats. The serum NE contents in the two model groups (young and aged) were higher respectively than the two control rats (young and aged). The following items’ contents were higher in the aged model rats than in the young model rats: serum NE, serum E, hypothalamus NE. The hypothalamus NE and E content was lower in the aged model rats than in te aged control rats. NPY level in the brain tissue was lower in the aged control rats than that in the young control rats and aged model rats (P＜0.05).CONCLUSION: The myocardial injury after brain ischemia-reperfusion was concerned with the enhanced excitability of sympathetic-adrenal system, espectially in the aged rats. However, the change in myocardial enzyme was not serious in the aged rats compared with young rats.