Effects of carbon monoxide inhalation on severe limb ischemia/reperfusion injury and its damages lead to shock / 中国应用生理学杂志

<p><b>OBJECTIVE</b>To study the protective effect of carbon monoxide (CO) inhalation on the serious limb ischemia/reperfusion (I/R) injury, and which effects caused to shock in rats.</p><p><b>METHODS</b>36 SD rats were randomly divided into I/R, I/R + CO (RC), sham operation (S) groups. I/R injury models were made by the occlusion of the femoral artery for 8 h and the reperfusion for 12 h, 10 d. Before reperfusion of 2 h, RC group started to breathe medical air containing CO (the volume fraction of CO: 0.075%) continuously, until after reperfusion for 4 h, a total of inhalation 6 h. S, I/R groups exposed to air, breathe freely. Caudal artery pressures (CAP), ten days survival rate, serum lactate dehydrogenase (LDH) and creatine kinase (CK) activity, limb wet - to - dry weight ratio (W/D) and the pathologic changes of limb were observed.</p><p><b>RESULTS</b>Once the reperfusion started, the CAP decreased rapidly in I/R group, and the mean reduced to(5.3259 +/- 0.3832) kPa when reperfusion for 8 h. Compared to I/R group, the CAP decreased slower and smaller in RC group, moreover, its mean reduced to (8.3300 +/- 0.4224) kPa when reperfusion for 8 h. The 10 d survival rate in I/R group was that 8 rats died all between reperfusion for 13 - 20 h. Only 1 rat died in RC group and the other 7 rats were still alive when reperfusion for 10 d. Compared to I/R group, the pathological features of the ischemic limb were significant ly improved, and the figures of W/D, serum LDH and CK value were remarkable lower in RC group (P < 0.05).</p><p><b>CONCLUSION</b>Inhaling exogenous low-dose CO has a reverse regulation in the blood pressure decline caused by serious limb I/R injury in rats. And at the same time, it can effectively prevent the occurrence of shock, reduce physical damage, significantly increase the survival rate of animals.</p>

Carbon monoxide inhalation protects against limb ischemia/reperfusion injury / 中国应用生理学杂志

<p><b>OBJECTIVE</b>To study the protective effect of carbon monoxide(CO) inhalation in the limb ischemia/reperfusion (I/R) injury of rats.</p><p><b>METHODS</b>Forty-four Sprague-Dawley rats were randomly divided into three groups: S, I/R and RC groups. I/R injury model was made by the occlusion of the femoral artery for four hours and the reperfusion for forty-eight hours. RC group was exposed to medical air mixed CO (the volume fraction of CO: 0.05%) during limb reperfusion in rats. The other two groups were exposed to the routine air. Gross morphology of the ischemic limb, wet-to-dry weight ratio (W/D), and skeletal muscle histopathology were observed. The apoptosis index and expression levels of Bax and Bcl-2 in the muscle were assessed with Flow Cytometry. The activities of serum lactate dehydrogenase (LDH) and creatine kinase (CK) were tested by Automatic Biochemical Analyzer.</p><p><b>RESULTS</b>Compared to I/R group, W/D, serum LDH and CK activities, the apoptosis index and Bax expression level in the muscle were all significantly decreased, the Bcl-2 expression level was significantly increased, gross morphology of the ischemic limb and muscle histopathology were obviously improved in RC group.</p><p><b>CONCLUSION</b>Inhaling exogenous CO can attenuate limb I/R injury.</p>

Exogenous carbon monoxide protects against liver injury induced by ischemia/reperfusion of hind limbs in rats / 中国应用生理学杂志

<p><b>AIM</b>To investigate the protective effect of exogenous carbon monoxide (CO) on the liver injury induced by ischemia/reperfusion (I/R) of hind limbs in rats.</p><p><b>METHODS</b>100 SD rats were divided randomly into sham operated group (S), S+ CO group (SC), I/R group (I/R), I/ R+ CO group (RC). A rat model of ischemia in hind limbs and the reperfusion liver injury was established with the occlusion of the femoral arteries for 4 h and re-opening for 6 - 72 h, 10 d. The rats in SC and RC groups were exposed to air containing CO (the volume traction of CO: 0.05%) for 2 h before and after reperfusion or the corresponding control time point, while the other two groups were exposed to the routine air. The pathologic changes of liver tissue were morphologically observed by HE stain. Serum GPT activity was tested by Automatic Biochemical Analyzer. The percentage of apoptosis, expression levels of bax and bcl-2 protein in liver tissue were detected by Flow Cytometry.</p><p><b>RESULTS</b>There was no difference between S and SC groups. Compared with SC group: (1) Pathological changes in liver tissue were significant in I/R and RC groups. (2) The serum GPT activity of I/R and RC groups was obviously increased. (3) In IR and RC groups, the percentage of apoptosis in liver tissue was all significantly increased. (4) The bax expression level was significantly increased. Compared RC group with I/R group: (1) Pathological change was slight. (2) The serum GPT activity was depressed. (3) The percentage of apoptosis and expression level of bax protein in liver tissue were depressed. (4) The expression level of bcl-2 protein in liver tissue was increased.</p><p><b>CONCLUSION</b>Exogenous CO could attenuate liver tissue injury induced by limbs I/R in rats.</p>