Protective Effect Of Penehyclidine Hydrochloride Pretreatment On Lipopolysaccharide-induced Acute Lung Injury In Rats

BackgroudAcute lung injury(ALI)is a common cause of acute respiratory in cardiopulmonary bypass open-heart surgery.Although the techniques of myocardium protection have been rapidly developed,ALI is common and remains a significant cause of morbidity and mortality in critical patients.Recently,the lung protection during the cardiopulmonary bypass procedure has become a research focus.It has been extensively reported that anisodamine has a protective effect on ALI.Recent studies showed that anisodamine could inhibit the release of cytokines such as TNF-α,IL-6 and IL-1β.This could reduce the inflammatory reaction.But,the action of anisodamine on M cholinoceptor is unselective,which have the same affinity while interacted with M1,M2 and M3 subtype of cholinoceptor,which usual obviously increase the heart rates while the treatment-dose was administered,this adverse effect of the anisodamine would not benefit patients who need recovery of heart function after operation,especially in patients who received coronary artery bypass graft(CABG)procedure.Penehyclidine hydrochlofide(PHC),a new anticholinergic drug invented by the Institute of Pharmacology and Toxicology,Academy of Military Medical Sciences in the People's Republic of China,which has the selective antagonism on M1 and M3 cholinoceptor,and no obvious antagonism on M2 cholinoceptor,which could obviate the tachycardia and blocked regulation function of presynaptic membrane M2 receptor which caused by anisodamine on account of scarcity of subtype selection on M cholinoceptor.Recently,both the animal experiment and clinical practice have demonstrated that a great quantity release of acetylcholine was the initiation factor of acute lung microcirculation disorder while ALI development, which make lung vascular continuously spasm.Some researches indicated that PHC can relieve blood vessel convulsion,ameliorate microcirculation and antagonize ischemic-reperfusion injury.Theoretically,penehyclidine hydrochloride is potentially beneficial for the treatment of ALI and has better clinical tolerance,it has wide perspective of application.ObjectivesThe aim of this study was to explore the potential protective effect of PHC pretreatment on in vivo lipopolysaccharide-induced model of acute lung injury in rats.Thereby,this study will provide experiment and theory support on application of PHC in patients who received CPB procedure to protect the development of ALI.Materials and MethodsThirty healthy Wistar rats(180-240 g)were randomly assigned into three groups(each group n=10):(1)control group:LPS was administered by caudal vein injection(LPS 5 mg/kg);(2)PHC group:LPS(5 mg/kg)plus PHC(0.02 mg/kg);(3)anisodamine group:LPS(5mg/kg)plus anisodamine(2 mg/kg).Each group rats brochoalveolar lavage fluid(BALF)were collected and wet to dry weight ratio(W/D)were determined after the injections were performed 6 hours.The tumor necrosis factor-α(TNF-α),interleukin 6(IL-6)and interleukin 1β(IL-1β)which contained in BALF supernatant were determined by enzyme linked immunosorbent assay(ELISA)method.ResultsAnalysis of the data of each group rats BALF supernatant cytokine content: (1)TNF-αlevel:both anisodamine group(217.3±38.1 ng/l)and PHC group (179.2±40.1 ng/l)were significantly lower than control group(298.4±57.0 ng/l)(P＜0.05),comparision of anisodamine group with PHC group that TNF-αlevel of PHC group significantly lower than anisodamine group(P＜0.05);(2)IL-6 level: both anisodamine group(451.3±114.2 ng/l)and PHC group(302.7±101.8 ng/l)were significantly lower than control group(711.9±162.7 ng/l)(P＜0.05), comparision of anisodamine group with PHC group that IL-6 level of PHC group significantly lower than anisodamine group(P＜0.05);(3)IL-1βlevel:both anisodamine group(108.7±21.7 ng/l)and PHC group(90.2±19.3 ng/l)were significantly lower than control group(147.4±38.5 ng/l)(P＜0.05),comparision of anisodamine group with PHC group that IL-1βlevel of PHC group significantly lower than anisodamine group(P＜0.05).Analysis of the data of each group rats lung W/D ratio demonstrated that anisodamine group(4.09±0.30)and PHC group(3.82±0.27)significantly lower than control group(4.52±0.50)(P＜0.05).Comparision of anisodamine group with PHC group that W/D ratio of PHC group significantly lower than anisodamine group(P＜0.05).Conclusions1.PHC could significantly reduce lipopolysaccharide-induced ALI rats BALF supernatant TNF-α,IL-6 and IL-1βlevel,which indicated that PHC could improve function of microcirculation and exert protective effect on ALI induced by LPS.2.The comparison of the PHC to anisodamine that PHC could more significantly reduce lipopolysaccharide-induced ALI rats BALF supernatant TNF-α, IL-6 and IL-1βlevel than anisodamine,which indicated that PHC could specially antagonize on M1 and M3 cholinoceptor and exert more protective effect on ALI induced by LPS.3.Both anisodamine and PHC could significantly decrease W/D ratio,which indicated that anisodamine and PHC could improve function of microcirculation, exert protective effect on ALI induced by LPS;the comparison of the PHC to anisodamine that PHC could more significantly decrease W/D ratio,which indicated that PHC could exert more protective effect on ALI induced by LPS.