血液滤过对重症中暑休克犬内皮素和一氧化氮的影响

目的探讨血液滤过(hemofiltration,HF)对重症中暑休克犬内皮素(endothelin,ET)和一氧化氮(nitricoxide,NO)的影响。方法 16只健康雄性杂种犬,随机分为中暑对照组(HS组)和血液滤过组(HF组)各8只。采用整体高温来诱导犬重症中暑休克,模型成功后立即出舱,HS组置于常温下观察,HF组立即行HF治疗,观察两组犬各时间点血浆ET和血清NO含量及NO/ET值的变化。结果两组犬中暑前ET和NO含量及NO/ET值比较无统计学差异(P>0.05)。中暑休克时ET和NO含量及NO/ET值较中暑前明显升高(P<0.01),且两组之间比较无统计学差异(P>0.05)。休克后1h:HS组ET值上升,HF组ET值下降,与休克时比较均无统计学意义(P>0.05),但HF组ET明显低于HS组(P<0.05);HS组NO值升高,但无统计学意义,HF组NO值下降,低于休克时(P<0.05),HF组NO明显低于HS组(P<0.01);HS组NO/ET值略降低,HF组NO/ET值亦下降,但均无统计学意义(P>0.05),两组之间NO/ET比较亦无统计学意义(P>0.05);休克后2h和3h:HS组ET值继续上升明显高于休克时(P<0.01),HF组ET值逐渐下降明显低于休克时(P<0.01),HF组ET值明显低于HS组(P<0.01);HS组NO值继续上升,但与休克时比较无统计学意义(P>0.05),HF组NO逐渐下降,明显低于休克时(P<0.01),HF组NO明显低于HS组(P<0.01);HS组NO/ET略低于休克时,但无统计学意义(P>0.05),HF组NO/ET值明显低于休克时(P<0.01),HF组NO/ET值明显低于HS组(P<0.01)。结论重症中暑休克犬会出现血浆ET和血清NO的升高及NO/ET值的失调,HF可清除血中异常升高的ET和NO,并恢复NO/ET值,而清除NO和ET可能是HF治疗重症中暑时稳定其血压和改善微循环灌注的重要机制之一。

Effects of hemofiltration on endothelin and nitric oxide in severe heat stroke dogs with shock

Objective To explore the effects of hemofiltration on endothelin and nitric oxide in severe heat stroke dogs with shock.Methods Sixteen healthy male hybrid dogs were randomly divided into 2 groups,8 for each:as heat stroke group(HS group)and hemofiltration group(HF group).Severe heat stroke model was induced with high temperature.The dogs were taken out of the heating cabin as soon as it reached heat stroke level,then observed under normal temperature with no treatment.The HF group accepted hemofiltration treatment immediately.The changes of ET,NO,NO/ET of two groups of dogs were observed and compared.Results The value of the ET,NO,NO/ET were compared,there were no significant differences(P>0.05)between two groups before heatstroke.The value of ET,NO,NO/ET of the dogs were all higher when got heat stroke and the two groups of dogs showed no significant difference(P>0.05).One hour after heat stroke,the ET of HS group rose continually while HF group declined,but there were no difference comparing with the time of got heat stroke.The value of ET in HF group was lower than HS group(P<0.05).The NO of HS group rose but showed no significant difference(P>0.05),while in HF group the NO declined and showed significant difference(P<0.01).The value of NO in HF group was lower than HS group(P<0.01).The ratio of NO/ET in HS group and HF group all declined and showed no significant difference(P>0.05).There was no significant difference in NO/ET between two groups at this time(P>0.05).After two and three hours,comparing with the time of got heat stroke,the value of ET in HS group rose apparently and showed significant difference(P<0.01),the value of ET in HF group slowly declined and showed significant difference(P<0.01).The value of ET in HF group was obviously lower than HS group(P<0.01).The value of NO in HS group still rose but showed no difference(P>0.05),the value of NO in HF group continuously declined and showed significant difference(P<0.01).The value of NO in HF group was lower than HS group(P<0.01).The ratio of NO/ET in HS group was little lower comparing with the time of got heat stroke,but showed no significant difference(P>0.05).The ratio of NO/ET in HF group declined and showed significant difference(P<0.01)and apparently lower than HS group(P<0.01).Conclusions The value of plasma ET and serum NO will rise and the balance of NO/ET will be disturbed in dogs with severe heat stroke caused shock,hemofiltration can remove the ET and NO from blood,and renew the ratio of NO/ET,so the clearance of ET and NO from blood by HF may be one of the important mechanism in stabilizing the blood pressure and improving circumfusion in dogs with severe heat stroke.