Effect of induced hypothermia resuscitation on the expression of Ca2+/calmodulin-dependent protein kinase Ⅰ in intestinal tis-sues of rats with hemorrhagic shock

BO Qi; WANG Xin-yu; LIU Dan; ZHANG Cheng

doi:10.16048/j.issn.2095-5561.2023.05.03

Abstract：Objective To investigate the effect of induced hypothermia resuscitation on the expression of Ca2+/calmodulin-dependent protein kinase I(CaMK Ⅰ)in intestinal tissue of rats with hemorrhagic shock.Methods A total of 30 adult male Wistar rats were randomly divided into sham operation group(n=6),normal temperature resuscitation group(n=12)and low temperature resuscitation group(n=12).The sham operation group only performed surgical intubation and related operations,and did not establish hemorrhagic shock model.Each rat in the normal temperature resuscitation group and the low temperature resuscitation group was bloodlet 25 ml/kg,and the hemorrhagic shock model was established.After 60 minutes of shock,the rats were resuscitated at 38℃and 32℃respectively and maintained for 60 minutes.After the resuscitation,the rats'body temperature was restored to 38℃and the hemodynamics were monitored for 3 hours.After 3 hours of resuscitation,50%of the rats in all 3 groups were randomly selected to be killed,and the intestinal mucosa,mesenteric lymph nodes and blood were collected.The survival of the remaining rats was analyzed for 72 hours.Quantitative polymerase chain reaction(PCR)and western blot were used to detect the expression of CaMKⅠ mRNA and protein in the intestinal mucosa of the three groups of rats,and the expression of serum inflammatory factors was detected by enzyme-linked immunosorption kit.Meanwhile,bacterial translocation was detected.Results After 3 hours,the heart rate and mean arterial pressure(MAP)of the low-temperature resuscitation group were lower than those of the normal temperature resuscitation group,while the cardiac output,stroke volume and ejection fraction were higher than those of the normal temperature resuscitation group,and the differences were statistically significant(P<0.05).All the rats in the sham operation group survived at 72 h as the end point.The average survival time of rats in the low-temperature resuscitation group was(63.50±9.59)h,which was significantly longer than that in the normal temperature resuscitation group(46.83±19.59)h,and the difference was statistically significant(P<0.05).After 3 hours of liquid resuscitation,the mRNA expression level and gray value of CaMK Ⅰ in the low-temperature resuscitation group were significantly lower than those in the normal temperature resuscitation group,with statistical significance(P<0.05).The mRNA and protein expression levels of CaMKⅠ in the normal temperature resuscitation group and the low temperature resuscitation group were significantly higher than those in the sham operation group,with statistical significance(P<0.05).Serum CaMKⅠ and tumor necrosis factor-α(TNF-α),interleukin(IL)-1β,IL-6 and IL-8 of sham operation group ratswere significantly lower than those of normal temperature resuscitation group and low temperature resuscitation group.The level of IL-10 was higher than that of normal temperature resuscitation group,but lower than that of low temperature resuscitation group,the difference was statistically significant(P<0.05).The levels of CaMK Ⅰ,TNF-α,IL-1β,IL-6 and IL-8 in serum of rats in low-temperature resuscitation group were significantly lower than those in normal temperature resuscitation group,and the levels of IL-10 were significantly higher than those in normal temperature resuscitation group,with statistical significance(P<0.05).After 3 hours of resuscitation,the blood bacterial displacement and mesenteric lymph node bacterial displacement of rats in the low-temperature resuscitation group were significantly lower than those in the normal temperature resuscitation group,and the difference was statistically significant(P<0.05).Conclusion Under induced hypothermia resuscitation condition,mRNA and protein levels of CaMK Ⅰ in intestinal tissues of hemorrhagic shock rats were decreased,survival time of rats was prolonged.Down-regulation of CaMK Ⅰ may be an important molecular mechanism of induced hypothermia resuscitation to alleviate intestinal ischemia-reperfusion injury in rats with hemorrhagic shock.