ABSTRACT
Aim To explore the effect of Buyang Huanwu Decoction on cerebral ischemia-reperfusion injury in rats by regulating autophagy through PI3K/AKT pathway. Methods The rats were randomly divided into five groups(n=10): sham operation group(Sham), model group(Model), Buyang Huanwu Decoction group(BYHWD), PI3K inhibitor group(LY294002)and Vehicle group(Vehicle). Except Sham group, the other groups were treated with 2h ischemia and 72 h reperfusion for modeling. The Zea Longa score was used to assess the neurological defects, HE was used to observe brain injury in the ischemic penumbra(IP), immunofluorescence was employed to detect LC3, and Western blot was used to detect pathway and autophagy marker proteins. Results Compared BYHWD group with model group, the neurological score of rats decreased, cerebral infarction volume decreased, the pathological lesions of brain IP were relieved, PI3K and p-AKT/AKT expression increased, and LC3Ⅱ/ decreased and p62 increased(P<0.05). The regulatory effect of BYHWD was weakened by LY294002(P<0.05). Conclusion Buyang Huanwu Decoction alleviates cerebral ischemia-reperfusion injury in rats by activating PI3K/AKT pathway to inhibit autophagy.
ABSTRACT
Aim To explore the mechanism of Buyang huanwu decoction attenuating cerebral ischemia-reper- fusion injury in rats by regulating autophagv through AMPK/mTOR/ULKl signaling pathway.Methods Left eerebral ischemia model in rats was established by modified thread ocelusion method, then the rats in each group were given medieine onee every 24 hours for 3 times.After 72 hours of reperfusion, the nerve injury and the changes of cerebral infarction volume were observed; the morphology, number and apoptosis of nerve cells were observed by Nissl staining and TUNEL staining; the expression of autophagy protein and AMPK/mTOR/LJLKl autophagy signaling pathway related proteins were detected by Western blot.Results Buyang huanwu decoction could improve the neurological deficit of rats, reduce the volume of cere bral infarction and neuronal apoptosis, reduce the pathological injury of brain tissues, inhibit the phosphorylation activation of AMPK, relieve the inhibition of AMPK on downstream mTOR and LJLK1 , promote the phosphorylation activation of both, and inhibit autophagy.AMPK agonist metformin increased the level of autophagy and reversed the protective effect of Buyang huanwu decoction on cerebral ischemia-reperfusion injury in rats.Conclusion Buyang huanwu decoction mediates AMPK/mTOR/ULKl autophagy signaling pathway to play a neuroprotective effect on cerebral is- chemia-reperfusion injury in rats.
ABSTRACT
Objective: Clonidine, by activating peripheral α-adrenoceptors, produces transient pressor response after i. v. injection in anesthetized animals. Moxonidine, with at least 40-fold higher affinity to I1-imidazoline receptors than to α2-adrenoceptors, produces also a transient pressor response. This work was designed to investigate whether I1-imidazoline receptors are involved in this pressor effect of moxonidine. Methods: Female spontaneously hypertensive rats (SHRs, aged 14-16 weeks) were anesthetized with urethane. To observe the transient pressor responses, moxonidine 0. 1, 0. 3, 1. 0 mg/kg (intravenous, i. v.), 2.0 μg (intracerebroventricular, i. c. v.) and 1.0, 10.0 mg/kg (intragastric, i. g.) were administrated in different groups of rats. To evaluate the roles of α1-adrenoceptors, α2-adrenoceptors and I1-imidazoline receptors in the transient pressor responses to moxonidine, prazosin (10.0 μg/kg), yohimbine (2.0 mg/kg), phentolamine (0.2 mg/kg), idazoxan (1.0 mg/kg) or yohimbine + idazoxan (2.0 mg/kg + 1.0 mg/kg) were intravenously given to the animals before moxonidine 0.3 mg/kg i. v.). Results: It was found that i. v. moxonidine produced a greater pressor response than clonidine when producing a similar reduction of blood pressure. This effect of moxonidine was not influenced by prazosin, but was partly inhibited by yohimbine, phentolamine or idazoxan, and completely blocked by the combination of yohimbine and idzaxon. Neither i. c. v. injection nor i. g. administration of moxonidine induced transient pressor responses. Conclusion: The transient pressor response of i. v. moxonidine is mediated by both peripheral I1-imidazoline receptors and α2-adrenoceptors.
ABSTRACT
Objective:Clonidine,by activating peripheral α-sbrenoceptors, produces transient pressor response after i.v.injection in anesthetized animals.Moxonidine, with at least 40-fold higher affinity to I1-imidazoline receptors than to α2-adrenoceptors,produces also a transient pressor response. This work was designed to investigate whether I1-imidazoline receptors are involved in this pressor effect of moxonidine. Methods:Female spontaneously hypertensive rats(SHRs,aged 14-16 weeks)were anesthetized with urethane.To observe the transient pressor responses,moxonidine 0.1,0.3,1.0mg/kg(intravenous,i.v),2.0μg(intracerebroventricular,i.c.v.)and 1.0,10.0mg/kg(intragastric,i.g.)were administrated in different groups of rats.To evaluate the roles of α1-adrenoceptors,α2-adrenoceptors and I1-imidazoline receptors in the transient pressor responses to moxonidine, prazosin(10.0μg/kg),yohimbine(2.0mg/kg),phentolamine(0.2mg/kg),idazoxan(1.0mg/kg)or yohimbine+idazoxan(2.0mg/kg+1.0mg/kg)were intravenously given to the animals before moxonidine 0.3mg/kg (i.v.).Results:It was found that i.v.moxonidine produced a greater pressor response than clonidine when producing a similar reduction of blood pressure.This effect of moxonidine was not influenced by prazosin, but was partly inhibited by yohimbine, phentolamine or idazoxan,and completely blocked by the combination of yohimbine and idzaxon.Neither i.c.v.injection nor i.g. administration of moxonidine induced transient pressor responses.Conclusion:The transient pressor response of i.v. moxonidine is mediated by both peripheral I1-imidazoline receptors and α2-adrenoceptors.
ABSTRACT
Objective:Clonidine,by activating peripheral α-sbrenoceptors, produces transient pressor response after i.v.injection in anesthetized animals.Moxonidine, with at least 40-fold higher affinity to I1-imidazoline receptors than to α2-adrenoceptors,produces also a transient pressor response. This work was designed to investigate whether I1-imidazoline receptors are involved in this pressor effect of moxonidine. Methods:Female spontaneously hypertensive rats(SHRs,aged 14-16 weeks)were anesthetized with urethane.To observe the transient pressor responses,moxonidine 0.1,0.3,1.0mg/kg(intravenous,i.v),2.0μg(intracerebroventricular,i.c.v.)and 1.0,10.0mg/kg(intragastric,i.g.)were administrated in different groups of rats.To evaluate the roles of α1-adrenoceptors,α2-adrenoceptors and I1-imidazoline receptors in the transient pressor responses to moxonidine, prazosin(10.0μg/kg),yohimbine(2.0mg/kg),phentolamine(0.2mg/kg),idazoxan(1.0mg/kg)or yohimbine+idazoxan(2.0mg/kg+1.0mg/kg)were intravenously given to the animals before moxonidine 0.3mg/kg (i.v.).Results:It was found that i.v.moxonidine produced a greater pressor response than clonidine when producing a similar reduction of blood pressure.This effect of moxonidine was not influenced by prazosin, but was partly inhibited by yohimbine, phentolamine or idazoxan,and completely blocked by the combination of yohimbine and idzaxon.Neither i.c.v.injection nor i.g. administration of moxonidine induced transient pressor responses.Conclusion:The transient pressor response of i.v. moxonidine is mediated by both peripheral I1-imidazoline receptors and α2-adrenoceptors.