This study was performed to establish an experimental model of ischemia for the investigation of new treatment modality of limb-threatening ischemia. We produced ischemia in the hindlimbs of 8 New Zealand white rabbits. Under general anesthesia, the left femoral artery was exposed, freed, and excised from distal external iliac artery to proximal popliteal and saphenous arteries. And then both hindlimbs were serially examined to assess the ischemia according to the time table until postoperative 6 weeks. We assessed clinical observation, blood pressure, radioisotopic perfusion scan, and angiography. Clinical ischemic changes of the operated feet were observed in 63%. The blood pressure of left calves was measurable on postoperative day 3 (p<0.05, vs preoperative day 2) and then gradually increased to reach a plateau in postoperative week 6. Radioisotopic arterial perfusion showed similar profiles as in blood pressure. Angiography of ischemic hindlimbs demonstrated a few collateral vessels arising from the internal iliac artery with the reconstitution of the posterior tibial artery in postoperative week 2. In postoperative week 6, collaterals remained the same in number. However, these became dilated and tortuous and showed reconstitution in distal hindleg. In conclusion, this is a reproducible, measurable, and economical animal model of hind limb ischemia.
Angiography ; Animal ; Blood Pressure ; *Disease Models, Animal ; Hindlimb/*blood supply ; Ischemia/*physiopathology/radiography ; Male ; Rabbits

OBJECTIVETo observe the effects of polyethylene oxide (PEO) on microcirculation of normal rat hindlimb skeletal muscle.

METHODSSixteen male Wistar rats were anesthetized and equally and randomly divided into PEO group (administered with 10 ppm PEO solution) and control group (administered with equal volume of normal saline). The PEO solution or saline was separately injected through the caudal vein at a constant rate of 5 ml/h for 20 minutes. Using short axis view at right mid thigh region, contrast-enhanced ultrasonography was performed before and after the administration of solution. Electrocardiogram, blood pressure, and central venous pressure were also monitored.

RESULTSIn the PEO group, after the administration of PEO, microcirculation capillary volume increased from (20.78±2.63) dB to (22.40±1.94) dB (P=0.023), red blood cell velocity from (0.27±0.08) s-1 to (0.35±0.13) s-1(P=0.010), and capillary blood flow from (5.65±1.81) dB/s to (7.91±3.28) dB/s (P=0.013). In the control group, there were no significant changes in microcirculation capillary volume, red blood cell velocity, and capillary blood flow (all Pþ0.05) after the injection of normal saline. The changes of heart rates, blood pressures and central venous pressure were not significant after the administration of either PEO or saline (all Pþ0.05).

CONCLUSIONPEO can remarkably increase capillary volume, red blood cell velocity, and capillary blood flow in normal rat hindlimb skeletal muscle.

Animals ; Hindlimb ; blood supply ; Male ; Microcirculation ; drug effects ; Muscle, Skeletal ; blood supply ; Polyethylene Glycols ; pharmacology ; Rats ; Rats, Wistar

OBJECTIVETo observe the change of nitric oxide (NO) levels in the blood and the morphological change of the muscles in the limbs of rats during the (IR) injury and after being intervened by L-arginine (L-Arg) and L-nitroarginine (L-NNA).

METHODSSixty-six male Sprague-Dawley (SD) rats were used an d grouped into the normal controls, the sham injury controls, the IR injury group and the intervention groups (L-Arg group and L-NNA group). After 6 hours of ischemia, followed by reperfusion for 3, 12 or 24 hours, the samples in the IR injury group were obtained. The rats in the intervention groups were given L-Ar g (100 mmol/L) and L-NNA (10 mmol/L), respectively, through the abdominal cavity. Then the anterior tibial muscle in the right limb was obtained for histological examination, the anterior tibial muscle in the left limb for ultrastructure observation and the blood for assay of NO in all the rats. NO was assayed by indirect measurement of NO(2)(-)/NO(3)(-) with Griess method.

RESULTSThere was no significant difference of NO between the normal controls and the sham injury controls (P>0.05). But NO significantly decreased in the IR injury group (P<0.01), and further decreased with reperfusion (P<0.01) and reached the lowest point at 12 hours after reperfusion. The level of NO in the L-Arg group was significantly higher than that in the IR injury group ( P<0.01), but was not significantly different from that in the controls (P>0.05). In the L-NNA group, NO decreased to the undetectable level (P<0.01). Histological examination and ultrastructure observation showed the muscles were normal in the control groups. After 6 hours of ischemia, the skeletal muscles displayed injuries, and they were most severely injure d after 12 hours of reperfusion. In the L-Arg group, the skeletal muscles were less injured, while in the L-NNA group, the injury was similar to that in the I R injury group.

CONCLUSIONSWhen the limbs of the rats sustain IR, NO in the blood decreases. Meanwhile, the muscles in the limbs are injured. When L-Arg is given, NO in the blood is restored and the muscles are protected. When L-NNA completely inhibits NO, no protection of the muscles is shown.

Animals ; Arginine ; pharmacology ; Hindlimb ; Male ; Muscle, Skeletal ; blood supply ; ultrastructure ; Nitric Oxide ; physiology ; Rats ; Rats, Sprague-Dawley ; Reperfusion Injury ; physiopathology

Animals ; Hindlimb ; blood supply ; Ischemic Preconditioning ; Lung ; metabolism ; Male ; P-Selectin ; metabolism ; Rats ; Rats, Wistar ; Reperfusion Injury ; metabolism

OBJECTIVETo investigate the preventive effects of Salvia miltiorrhiza (SM) on multiple organ edema in the rats which suffered from hind limb ischemia/reperfusion( LI/R).

METHODSTwenty four Wistar rats were randomly divided into 3 groups (n = 8): control group (C group), ischemia/reperfusion group (I/R group ), Salvia miltiorrhiza group (SM group). Referring to Tourniquet method, the model rats which underwent 4 hours ischemia and 4 hours reperfusion of hind limbs were made. Thirty minutes before reperfusion, SM was given to the rats in SM group by tail vein injection at the dose of 5 mL/kg. Accurately weighed one gram of heart, liver, kidney, lung, brain, intestine and skeletal muscle from every animals, weigh these specimens after baking (60 degrees C, 55 hours), calculated the ratio of wet and dry (Wet/Dry,W/D). The levels of interleukin-1 (IL-1) ,interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-alpha) in plasma and the contents of Superoxide dismutase (SOD) and malonaldehyde (MDA) were measured. The morphologic changes of skeletal muscle were observed with microscope.

RESULTSIt was found that after suffering from ischemia/reperfusion, the W/D of every specimens increased in different degree (P < 0.05, P < 0.01). In plasma, the values of SOD decreased but MDA increased obviously (P < 0.05, P < 0.01). The levels of IL-1, IL-6 ,TNF-alpha-a in plasma increased (P < 0.05, P <0.01). After LI/R, infiltration of inflammatory cells, broaden interstitial around muscle fiber and disordered arrangement of muscle fibers could be seen under microscope. However, Compared with LI/R group, W/D and levels of serum inflammatory factors in SM group were all lower, the values of SOD in plasma increased but MDA in plasma failed down. Pathological changes in skeletal muscle were improved.

CONCLUSIONLimb ischemia/reperfusion can lead to multiple organ edema, Salvia miltiorrhiza can prevent the edema in some degree by anti-oxidation and anti-inflammation.

Animals ; Cytokines ; blood ; Edema ; pathology ; prevention & control ; Hindlimb ; blood supply ; Male ; Malondialdehyde ; blood ; Rats ; Rats, Wistar ; Reperfusion Injury ; pathology ; prevention & control ; Salvia miltiorrhiza ; Superoxide Dismutase ; blood

The effects of local injection of genistein on femoral, renal, and mesenteric vascular beds were investigated respectively by constant flow perfusion method in 72 anaesthetized rats. The results are as follows: (1) genistein (0.4, 0.8, 1.2 mg/kg) decreased the perfusion pressure (PP) of femoral vascular bed in a dose-dependent manner. The effect of genistein (0.8 mg/kg) was partially inhibited by L-NAME, or by sodium orthovanadate (50 microg/kg), a potent inhibitor of protein tyrosine phosphatase; (2) genistein also decreased the PP of renal vascular bed in a dose-dependent manner and the effect of genistein was completely inhibited by pretreatment with sodium orthovanadate, but unaffected by L-NAME; and (3) genistein decreased the PP of mesenteric vascular bed in a dose-dependent manner, an effect which was partially inhibited by sodium orthovanadate, but unaffected by L-NAME. From the results obtained, it is concluded that genistein can decrease the vascular tone in the femoral, renal, and mesenteric vascular beds with the underlying mechanism that involves tyrosine kinase inhibition, while in femoral arterial beds, it also involves NO release.
Animals ; Genistein ; pharmacology ; Hindlimb ; blood supply ; Kidney ; blood supply ; Male ; Mesentery ; blood supply ; Perfusion ; Protein Kinase Inhibitors ; pharmacology ; Protein-Tyrosine Kinases ; antagonists & inhibitors ; Rats ; Rats, Sprague-Dawley ; Vasodilation ; drug effects

Animals ; Arterial Occlusive Diseases ; physiopathology ; therapy ; Dogs ; Genetic Therapy ; Hepatocyte Growth Factor ; genetics ; Hindlimb ; blood supply ; Ischemia ; physiopathology ; therapy ; Male ; Plasmids

AIMTo detect the changes of inducible heme oxygenase (HO-1) expression in liver following ischemia/reperfusion (I/R) of hindlimbs and to elucidate their significance.

METHODSI/R was established using the occlusion of the femoral arteries for 4h and reopening for 2-24 h in rats. The expression of HO-1 mRNA and HO-1 protein in liver tissue were detected with reverse transcription-polymerase chain reaction (RT-PCR) and immunohistochemical technique, respectively. The observation of pathologic changes of liver was made following the inhibition of HO-1 by zinc protoporphyrin (ZnPP).

RESULTSCompared with control groups, the relative expression level of HO-1 mRNA significantly increased in I/R group. There were more HO-1 positive hepatocytes in I/R group than control groups. The pathologic changes of liver tissue became more severe in I/R + ZnPP group.

CONCLUSIONThe expressions of HO-1 mRNA and protein in liver tissue are significantly upregulated, induction of HO-1 is involved in protection for hepatocytes during the I/R of hindlimbs.

Animals ; Gene Expression ; Heme Oxygenase (Decyclizing) ; genetics ; metabolism ; Hindlimb ; blood supply ; Liver ; metabolism ; RNA, Messenger ; genetics ; Rats ; Rats, Sprague-Dawley ; Reperfusion Injury ; metabolism

Animals ; Hindlimb ; blood supply ; Intestine, Small ; metabolism ; Ischemia ; metabolism ; prevention & control ; Ischemic Preconditioning ; Lung Injury ; metabolism ; Male ; Muscle, Skeletal ; metabolism ; Rats ; Rats, Wistar ; Reperfusion Injury ; metabolism

OBJECTIVETo explore the role of myeloperoxidase (MPO) and tumor necrosis factor-α (TNF-α) in myocardial injury induced by hind-limb ischemia-reperfusion (IR) in rats.

METHODSRat models of bilateral hindlimb IR established using a tourniquet were randomized into 9 groups, including a normal control group normal, 2 ischemic groups with hindlimb ischemia for 2 and 4 h, and 6 IR groups with a 4-h ischemia followed by reperfusion for 0.5, 2, 4, 6, 12, and 24 h. The plasma and myocardial levels of MPO and TNF-α in each group were measured, and the myocardial expression of TNF-α was determined with immunohistochemistry.

RESULTSCompared with the normal control group, the rats with a 2-h ischemia showed significantly increased levels of MPO and TNF-α in the plasma and myocardium. Compared with those in rats with a 4-h ischemia, the plasma and myocardial MPO levels increased significantly at 0.5 and 2 h of reperfusion, respectively; the plasma TNF-α level increased significantly at 4 h of reperfusion and myocardial TNF-α level decreased obviously at 12 h; plasma levels of MPO and TNF-α both significantly decreased at 24 h. The plasma MPO and TNF-α and myocardial TNF-α reached the peak levels at 4 h of reperfusion, and the peak myocardial MPO level occurred at 6 h. Immunohistochemistry showed that TNF-α positivity moderately increased after hindlimb ischemia, and further increased at 4 h of reperfusion but obviously reduced at 24 h.

CONCLUSIONThe activation of systemic and local neutrophils and inflammatory cytokines may play an important role in myocardial injury induced by hindlimb IR in rats.

Animals ; Disease Models, Animal ; Hindlimb ; blood supply ; Ischemia ; metabolism ; Male ; Myocardium ; metabolism ; Peroxidase ; metabolism ; Rats ; Rats, Wistar ; Reperfusion Injury ; metabolism ; Tumor Necrosis Factor-alpha ; metabolism