Effects Of Hydrogen Sulfide On Pulmonary Surfactant In Acute Lung Injury Induced By Organophosphate In Rats

Objective: To observe the effect of H2S on pulmonary surfactant in Acute LungInjury induced by organophosphate in rats, and explore its mechanism of action,providing experimental evidence for the clinical treatment of organophosphatepoisoning.Methods:Rat with acute lung injury was induced by organophosphate poisoning. Ratswere randomly divided into following group including control group, DDVPgroup(DDVP22mg/kg in intraperitoneal injection) DDVP+NaHS low-dosegroup(NaHS0.72mg/kg in intraperitoneal injecti), DDVP+NaHS dose group(NaHS1.56mg/kg in intraperitoneal injection), DDVP+NaHS high-dose group(NaHS3.12mg/kg in intraperitoneal injection)， DDVP+PPG group(PPG2ml/kg inintraperitoneal injection). NaHS, PPG and volume of saline were intraperitoneal3hours after modeling.Six rats were selected to determine lung wet and dry weight ratioin each group, and other six carried lavage, after lavage specimens preserved.Toobserve each group of animals lung injury by HE staining, and using RT-PCRmethod to detect expression of pulmonary surfactant protein A, B, C (SP-A, B, C)mRNA gene in the lung. Automatic Biochemical analyzer used to detect content oftotal protein (TP) and total phospholipid (TPL) content detect by the digestion methodin bronchoalveolar lavage fluid (BALF).Resuls:1.Rat poisoning after the performancePoisoned rats，Warped tail， salivation, urinary incontinence, muscle tremors,and accompanied by agitation, standing instability, and breathing difficultiesassociated with.DDVP+NaHS in highdose groups，middle and Low dose groupsafter treatment, symptoms were alleviated in varying degrees, exacerbation ofDDVP+PPG group. 2.the morphological changes of lung tissueGeneral view:The surface of lung in control group group was pale pink andsmooth without hemorrhagic foci and edema. The appearance of DDVP group wassignificantly congestion and edema, red with dark red hemorrhagic foci on surface.The damages to the lung tissue of the DDVP+NaHS low-dose group, DDVP+NaHSdose group, and DDVP+NaHS high-dose groupwere mitigated sequentially versusthe DDVP group. Compared with the DDVP group, the appearances of the DDVP+PPG group were serious red of the lung tissue, large tracts of hemorrhagic foci, severecongestion and edema in the lung tissue.Microscope view：The blank control group alveolar structural integrity,lung tissue inDDVP group was significantly impaired, alveolar septal thickening, alveolar integrityis compromised, cavity exudation, infiltration of inflammatory cells。DDVP+NaHSlow, middle and high dose group, the damage was compared with the DDVP group,DDVP+PPG group than in DDVP group increased the degree of lung injury.3.Rat lung wet/dry weight ratio of changeDDVP group compared with the control group, the lung wet/dry weight ratioincreased significantly(P<0.01)。Compared with DDVP group, DDVP+NaHS low,middle, high dose group of the lung wet/dry weight ratio were significantly reduced。(P<0.05or p<0.01)，DDVP+PPG group of above two indexes increased, but not hasstatistically significant (P>0.05)。4.Changes ofthe contents of TP and TPL in Bronchoalveolar lavage fluid（BLAF)DDVP group compared with the control group, The TP Content increased inDDVP group (P<0.01)、 The TPL Content decreases in DDVP group(P<0.01);Compared with the DDVP group, The TP in DDVP+NaHS low, middle,high dose group of decrease(P<0.01), The TPL in DDVP+NaHS low, middle dosegroup of Increased(P<0.01).Compared with the DDVP group, The TP Contentincreased in DDVP+PPG group(P<0.05)、The TPL Content decreases in DDVP+PPGgroup (P<0.05) 5.Changes of Sp-A,SP-Band SP-CmRNA geneexpression in lung tissueExpression in the lung tissue of rats, SP-A、SP-B and SP-C mRNA genecompared with blank control group decreased in DDVP group(P<0.01).Comparedwith the DDVP group,DDVP NaHS low, middle, high dose of lung tissue,significantly increased SP-A,B,C mRNA expression in rat (P<0.01);Compared withthe DDVP group,The expression of DDVP+PPG in lung tissue of SP-A group, theSP-B and SP-C mRNA gene decreased significantly.Conclusions:1.Exogenous H2S can reduce DDVPinduced ALI in rats by wet/dry weight ratiodecreased, bronchoalveolar lavage fluid TP decreased,TPL increased, alleviate thedegree of ALI induced by DDVP in rats.2. Exogenous H2S alleviate DDVP induced rat ALI process, may be related to theincrease in lung tissue of SP-A,SP-B and SP-CmRNA.