Objective To establish a new model on isolated human cadaver testes with ischemiareperfusion (I/R). MethodsThirteen isolated cadaver testes contributed by 13 persons were preserved under 0℃-4℃ hypothermia and then reperfused under 37℃. Histological and histochemical changes were observed. Results4℃ cold ischemia in 12 hours induced only trivial swelling and vascular degeneration of endothelial cells (ECs), obvious pathologic changes occurred after 24 hours, including detachment of ECs, separation between basement membrane and seminiferous epithelium, degeneration and detachment of spermatogenous cell and edema of mesenchyme. Injury was worse along with the prolongation of cold preservation time. Changes of LDH and SDH activities were found by histochemical staining. Reperfusion following 6 hours ischemia induced tissue injury and unusual enzyme activity. All changes were more obvious after reperfusion following 12,18,24 or 36 hours cold ischemia.Conclusion This new model on isolated cadaver testes with ischemiareperfusion is successful, it can substitute other solid organs of human beings for I/R injury study.
Local hypothermia as a preventive method to reperfusion injury of skeletal muscles was studied. Sixteen Japanese rabbits were divided into four groups at random. Before the tourniquet was inflated, a cold gel pack was applied to the right hind leg of each rabbit for 15 minutes to produce local hypothermic condition, without application of tourniquet the left hind limb was under local hypothermic condition as a control. The duration of tourniquet ischemia was 4 hours, and then reperfusion for one and two hours in the A and B groups respectively; in the C and D groups the duration of ischemia was 5 hours, and reperfusion for one and two hours, respectively. The muscle temperature averaged 16.6 degrees C with a needle thermocouple in the hind limb under local hypothermia. The serum K+, LA, SOD, LPO were determined from bilateral femoral veins, and electron and light microscopic studies of sural muscles were done in the post-reperfusion period. It was found that the K+, LA, LPO were lower than that of the control groups (P lt; 0.01), but SOD was higher than that of the control group (P lt; 0.01). Electron and light microscopic studies showed sight but reversible damage of muscular structure with the possibility of in the hypothermic groups cell regeneration. Basing on this experimental results, this method was applied in 45 cases reparative and reconstructive surgery of limbs. The duration of application of tourniquet averaged 2 hours and 57 minutes, the longest being 4 hours and 31 minutes, when the muscle temperature had reduced to 22.4 degrees C. There were no postoperative complications associated with this technique. Local hypothermia appeared to be a safe and effective method of decreasing the reperfusion damage after ischemia.
Objective To decrease the operative difficulty, with the purpose of looking for an orthotopic liver autotransplantation model which not only materializes the liver transplantation but also possesses higher survival rate. Methods This model was established via portal vein perfusion in thirty rats, and from which the result of the liver after perfusion, the operative time and the survival rate were observed. Liver tissues were researched at 24 h after operation under the light microscope. Results This model was easy to be perfused, the operative time was (48±3.0) min and the survival rate was 96.7% (29/30). The structure of hepatic tissue was basically normal with a little hydropic degeneration under the light microscope. Few erythrocytes residual occurred in the interlobular arteries under the light microscope. Conclusion The orthotopic liver autotransplantation model via portal vein perfusion has an exclusively blockage pattern which possesses a higher survival rate. It prevents the injury of immunological rejection and purely reflects the hepatic ischemia-reperfusion. But it is better to be applied in the non-hepatic artery anastomosis or the research nothing to do with the hepatic artery because the hepatic artery does not have sufficient perfusion.
To elucidate the mechanism of renal injury following intestinal ischemia/reperfusion, reactive oxygen metabolites in kidney and plasma were examined in 20 rats following intestinal ischemia/reperfusion by measurement of lipid proxidation (LP).The plasma lipid peroxide concentration after reperfusion was higher than that of the contol group (Ｐ＜0.01),the LP in kidney homogenate was also significantly higher (Ｐ＜0.01) following intestinal ischemia/reperfusion.Our study suggests that reactive oxygen metabolites after intestinal ischemia/reperfusion plays an important role in kidney injury.
Objective To investigate the pathological changes in the neuromuscular junction during ischemiareperfusion(IR) in the skeletal muscle. Methods Forty-eight healthy adult Wistar rats (24 male, 24 female) were equally randomised into the following 6 groups: Group A (control group): no ischemiareperfusion; Group B: ischemia by clamping the blood vessels of the right hindlimb for 3 hours; Group C: ischemia by clamping for 4.5 hours;Group D: ischemia by the clamping for 4.5 hours followed by reperfusion for 1.5hours; Group E: ischemia for 4.5 hours followed by reperfusion for 24 hours; and Group F: ischemia for 4.5 hours followed by reperfusion for 2 weeks. Then, the medial head of the gastrocnemius muscle flap model was applied to the right hindlimb of each rat. The medial head of the gastrocnemius muscle was isolated completely,leaving only the major vascular pedicle, nerve and tendons intact.The proximal and distal ends (tendons) were ligated while the vessel pedicle was clamped. And then, Parameters of the muscle (performance,contraction index,colour,edema,bleeding) were observed. The muscle harvested was stained with gold chloride(AuCl3) and the enzymhistochemistry assay (succinate dehydrogenase combined with acetylcholine esterase) was performed. Morphology and configuration of the neuromuscular junction were observed during the ischemiareperfusion injury by means of the AuCl-3 staining. The result of the enzymhistochemical reactions was quantitatively analyzed with the computer imageanalysis system. And then, additional 5 rats were prepared for 3 different models identical with those in Groups A, C and E separately. The specimens were harvested from each rat and were stained with HE and AuCl-3, and they were examined under the light microscope. Results During the period of ischemia, the skeletal muscle of Group B showed the colour of purple and edema.The colour and edema became worse in Group ,while dysfunction of elasticity and contraction appeared obviously with plenty of dark red hemorrhagic effusion at the same time.After reperfusion,the color and edema of muscle in Group D became improved while the elasticity and function of contraction was not improved. Hemorrhagic effusion of Group D turned clearer and less than Group C.Group E was similar to Group D in these aspects of muscle except for much less hemorrhagic effusion. Skeletal muscle in Group F showed colour of red alternating with white, adhesion,contracture of muscle, exposure of necrotic yellow tissue and almost lost all its functions. The AuCl3 staining showed that during IR, necrosis of the myocytes was followed by degeneration of their neuromuscular junctions, and finally the nerve fibers attached to these neuromuscular junctions were disrupted like the withering of leaves. The enzymhistochemistry assay showed thatthere was no significant difference in the level of acetylcholine esterase between the ischemic group (Groups B and C) and the control group (Group A) (Pgt;0.05). However, the level of acetylcholine esterase in all the reperfused groups (Groups D, E and F) decreased significantly when compared with the control group（Group A）and the ischemic groups (Groups B and C) (Plt;0.01). Conclusion The distribution of the nerve fibers and the neuromuscular junctions in the mass of the muscles is almost like the shape of a tree. The neuromuscular junction seems to be more tolerant for ischemia than the myocyte. Survival ofthe neuromuscular junction depends on its myocytes alive. Therefore, an ischemiareperfusion injury will not be controlled unless an extensive debridement of the necrotic muscle is performed.
Objective To compare the effect of two types of intermittent pressure on formation of pressure ulcer in rabbit hind l imbs and to investigate the mechanism of gradually changed intermittent pressure produced by waves bed in the prevention of pressure ulcer. Methods Gracil is (3 cm2) in both hind l imbs of 12 adult Japanese white rabbits were randomlyloaded with gradually changed intermittent pressure (50-160 mm Hg, 1 mm Hg=0.133 kPa) and sustained pressure (100 mmHg) serving as the experimental group and the control group, respectively. The experiment was terminated after 4 cycles, and a single cycle included 2 hours of compression and 30 minutes of compression-release. Blood velocity of hind l imbs and blood perfusion of wound were detected by bidirectional doppler blood flow detector and laser doppler perfusion imaging detection system before compression and at every 10 minutes in compression-release period of each cycle (0, 10, 20 and 30 minutes). After the termination, gross observation of the wound was conducted, pathomorphological changes of tissues from compressed area were observed by HE staining, and contents of NO, malondialdehyde (MDA), and superoxide dismutase (SOD) in muscle tissue were measured using colorimetry method. Results No significant difference was evident between two groups in terms of blood flow velocity before compression (P gt; 0.05); the blood flow velocity of two groups decreased significantly at 0 minute in every compressionrelease period of each cycle, and no significant differences were noted between two groups (P gt; 0.05); the blood flow velocity of theexperimental group was higher than that of the control group at 10, 20 and 30 minutes (P lt; 0.05). No significant difference was noted between two groups in terms of wound blood perfusion before compression (P gt; 0.05); the wound blood perfusion of two groups decreased significantly at 0 minute in every compression-release period of each cycle, and no significant differences were noted between two groups (P gt; 0.05); the difference between two groups was not significant at 10 minutes in the first cycle (P gt; 0.05), and the experimental group was higher than the control group at 20 and 30 minutes in the first cycle (P lt; 0.05). In the following 3 cycles, the recovery of perfusion in the experimental group was faster than that of the control group (P lt; 0.05). Gross observation showed the experimental group had less effusion than the control group. The experimental group had intact cutaneous appendage, less inflammatory cell infiltration, and no obvious ulcer formation, whereas the control group had obvious skin ulcer, depletion of cutaneous appendage, and more inflammatory cells infiltration. Significant differences were noted between two groups in terms of NO, MDA, and SOD content (P lt; 0.05). Conclusion Gradually changed intermittent pressure can maintain the blood perfusion of tissue, reduce ischemia-reperfusion injury and cell apoptosis, and prevent the formation of pressure ulcer.
目的 探讨磷丙泊酚钠后处理对大鼠肝脏缺血再灌注损伤的影响及是否呈剂量相关性。 方法 40只SD大鼠随机分为5组（每组n=8），即：假手术组（SP组）、生理盐水后处理组（NS组）、丙泊酚后处理组（PRO组）、低剂量磷丙泊酚钠[6 mg/（kg·h）]后处理组（LFOS组）、高剂量磷丙泊酚钠[12 mg/（kg·h）]后处理组（HFOS组）。除SP组外，其余4组在肝脏缺血60 min后给予药物后处理直至手术结束。在缺血60 min、再灌注60 min和120 min时采集血样，测定血清中丙氨酸氨基转移酶（ALT）、天门冬氨酸氨基转移酶（AST）、乳酸脱氢酶（ LDH）含量；在灌注120 min时取大鼠肝左外叶，用于HE染色，观察肝脏的形态学改变。 结果 与NS组相比，SP组、PRO组、LFOS组和HFOS组血清中的ALT、AST、LDH值明显降低（P＜0.05）；与SP组比较，PRO组、LFOS组、HFOS组和NS组的ALT、AST、LDH值升高（P＜0.05）；与PRO组比较，LFOS组的ALT、AST和LDH值差异无统计学意义（P＞0.05），HFOS组的ALT、AST和LDH值降低（P＜0.05）；LFOS组与HFOS组比较，HFOS组的ALT、AST和LDH值降低更为明显（P＜0.05）。 结论 磷丙泊酚钠后处理对大鼠肝脏缺血再灌注损伤具有保护作用，且高剂量磷丙泊酚钠[12 mg/（kg·h）]的保护作用更为明显，保护作用存在剂量依赖性。
Objective To study the efect of IH764-3 on ischemia-reperfusion (I/R) injury in rat liver. Methods Rats were divided into 3 groups, the control group was not subjected to ischemia and no treatment was given. I/R injury group was subjected to 40 minutes ischemia followed by reperfusion for 120 minutes. The IH7643 group (40mg/kg) was administred at ischemia and reperfusion. Results In the IH764-3 group, sereum levels of ALT, AST, AKP and γ-GT were significantly lower than those in the I/R group. Energy charge level recovery was significantly higher with IH7643 (P＜0.05), hepatic ultrastructure was better preserved with IH764-3. Conclusion IH764-3 may be useful in the treatment of hepatic ischemia reperfusion injury
Objective To study the effects of heat shock proteins (HSPs) in the course of hepatic ischemia reperfusion injury (HIRI), and analyze its mechanism. Methods The relationship between HSPs and HIRI was studied by reviewing literatures. Results HSPs was a kind of stress protein induced after cell was sitmulated by the stress. It could improve body′s tolerance to tough situation. Though hepatic ischemia reperfusion usually results in serious hepatic injury, at the same time it could induce can increase the production of HSPs that can protect liver from and lessen ischemia reperfusion injury. Conclusion HSPs can improve the tolerance to HIRI and lessen injury. In addition, HSPs is thought to be markers of HIRI, and can be used as a efficient indicator to test the level of hepatic injury and assess prognosis.
OBJECTIVE: To investigate the injury on isolated testes induced by ischemia/reperfusion(I/R), and the protective effect of Yisheng injection on the injury. METHODS: Twenty-six isolated cadaver testes contributed by 13 persons were preserved with 4 degrees C 250 ml hypertonic citrate alloxuric (HCA) solution and then reperfused with 37 degrees C 500 ml HCA. Solution of experimental group contained 500 micrograms/ml Yisheng injection. In simple cold preservation test, involving in 8 experimental and 8 control testes, a series of time points (6, 12, 18, 24, 36, 48, 60, 72 hours) were set to harvest. 10 testes (1 testis respectively on 6, 12, 18, 24 and 36 hours in experimental and control groups) were reperfused with 37 degrees C HCA for 6 and 12 hours. Histological and histochemical changes were observed. RESULTS: In the experimental testes, 4 degrees C cold preservation in 24 hours could not induce obvious pathologic changes. After 24 hours, changes such as swelling, vacuolar degeneration or detachment of endothelial cells (ECs), separation between basement membrane and seminiferous epithelium, mal-alignment of spermatogenous cell and edema of mesenchyme could be observed. In the testes preserved for 12 hours, the activity of lactic dehydrogenase(LDH) and succinic dehydrogenase (SDH) increased, then fallen after 24 hours. The activity of Nitric oxide synthetase(NOS) decreased after 18 hours. All changes were more obvious after following 37 degrees C reperfusion. In the control testes, swelling and vacuolar degeneration of ECs occurred on 12 hours cold preservation, and injury was worse along with the prolongation of cold preservation time. Pathologic changes of ECs, seminiferous epithelium and mesenchyme were serious after 37 degrees C reperfusion. CONCLUSION: 4 degrees C cold preservation in 24 hours can only cause mild ECs’ injury, and obvious abnormal testes’ histological profile can be observed beyond 24 hours. 37 degrees C reperfusion will make injury worse. Yisheng injection can keep isolated testes histologic structure well in 24 hours cold preservation, and it has protective effect on I/R injury.