Objective To investigate the effects of ecdysterone on the survival of the dorsal random-pattern skin flap with large length-to-width ratio in rats and its possible mechanisms. Methods Twenty-four healthy adult SD rats (male and/or female) weighing 200-250 g were randomly divided into the experimental group and the control group (n=12 per group).A caudally based dorsal random pattern skin flap, measuring 8 cm × 2 cm, was symmetrically raised. Ecdysterone (5 mg/kg) and normal sal ine (5 mg/kg) were injected into the abdominal cavity of rats in the experimental group and the control group at 10 minutes before operation and from the first to the fifth day after operation, respectively. The general condition of the rats was observed after operation. At 7 days after operation, the survival rate of the flap was detected, the superoxide dismutase (SOD) activity and the malonyldialdehyde (MDA) level were tested, HE and immunohistochemistry staining observation of the flap were performed. VIII factor dried microvessels in the middle part of the flap (4 cm far away from pedicle) were counted. Results All the rats survived until the end of the experiment. At 7 days after operation, the survival rate of the flap was 62.323% ± 7.046% in the experimental group and 47.753% ± 2.952% in the control group (P lt; 0.001); SOD activity was (54.560 ± 4.535) U/mgprot in the experimental group and (23.962 ± 3.985) U/mgprot in the control group (P lt; 0.001); MDA level was (8.445 ± 0.992) nmol/mgprot in the experimental group and (14.983 ± 0.929) nmol/mgprot in the control group (P lt; 0.001). Histology observation: compared with the control group, the inflammatory cells infiltration was less and the hyperplasia of fibers was more obvious in the experimental group. The microvessel counting in the middle part of the flap was 17.817 ± 2.420 in the experimental group and 8.967 ± 2.000 in the control group (P lt; 0.001). Conclusion Perioperative intraperitoneal injection of ecdysterone can promote the survival of the random-pattern skin flaps with large length-to-width ratio. Its mechanism may be related to its effects of improving SOD activity, decreasing l ipid peroxidation, and promoting angiogenesis of skin flaps.
Objective To explore the effect of oxygen inhalation on the retinae of newborn rats and its mechanism.Methods We mimicked the retinopathy of prematurity(ROP) by putting the newborn rats in high concentrated oxygen. One-day old rats were put into the oxygen box with the oxygen concentration of 80% for continuous 7 days; then in air condition for 7 days. The arterial blood oxygen pressure, retinal superoxide dismutase (SOD), and malondialdehyde (MDA) of the rats (1,2,4,7,8,9,11,14 days old) were examined. The diameter of retinal vessels′main branch and the coverage rate of peripheral vessels were measured in 7- and 14-day-old rats by ink perfusion. The retinal neovascularization of rats (8,9,11, 14 days old) were observed by HE staining. The rats of the same age fed in air condition were in the control group.Results The differential pressures of blood oxygen of rats (1,2,4,7 days old) in study group were significantly higher than those in the control group (P＜0.01), while the differential pressures of blood oxygen of rats (8,9,11,14 days old) in study group were lower than those in the control group (P＞0.05). The contents of SOD of the retinae in the rats ( 1,2,4,7,8 days old) were significantly lower than those in the control group(P＜0.01, P＜0.05 ), while the contents of MDA were significantly higher than those in the control group (P＜0.01,P＜0.05). The diameter of retinal vessels′main branch in 7-day rats was 75% of the control group, and the coverage rate of peripheral vessels was 22% of the control group; and was 61% and 73% respectively in 14-day-old rats. The neovascularization could be seen in 16.7% of the rats in the study group and nought in the control group.Conclusion The damage of free radical of the retina in high concentrated oxygen and hypoxia situation after oxygen supply may be one of the most important mechanism of ROP. (Chin J Ocul Fundus Dis，2003，19：269-332)
Objective To investigate the influence of chronic alcohol ingestion on the severity of acute lung injury (ALI) induced by oleic acid and lipopolysaccharide (LPS).Methods Thirty-two SD rats were randomly administrated with alcohol or water for 6 weeks，then instilled with oleic acid and LPS to induce ALI or with normal saline as control.Thus the rats were randomly divided into two injury groups [ethanol group and water group] and two control groups [ethanol group and water group] (n=8 in each group). PaO2,Wet to dry lung weight ratio (W/D)，levels of γ-glutamylcysteinylglycine (GSH) and malonaldehyde (MDA) in the lung tissue were measured.Results Compared to corresponding control groups，the PaO2 and GSH significantly decreased，and the lung W/D and MDA level were significantly increased in the injury groups (all Plt;0.05).In the injury groups，the changes of above parameters were more significant in the alcohol group than thoe in the water group (all Plt;0.05)，except the lung W/D with no significant difference.Conclusion Chronic ethanol ingestion was relevalent to oxidation/ antioxidation imbalance and more severe lung injury in rats with severe septic after trauma,which suggests that chronic alcohol abuse could increase the severity of acute lung injury.
Objective：To observe the histochemical changes of retinal photochemical damage in rats. Methods：The changes of retinal ultrastructure were observed.The concentration of malondaldehyde(MDA) was tested and the activity the histochemical change of cytochrome oxidase (CCO) and (Mg ++ -ATPasw) were evaluated on the retnal photochemical damage in SD rats. Results：At the 6th hour after light exposure,the swelling appwared at the nuclei of photoreceptor,the mitochondria of inner segment.The apical microvilli of RPE disappeared and lysosomes increased in RPE.On the 6th day after light exposure,the changes became more obvious.While on the 14th day after light expose the nuclei of photoreceptors and the inner segments renewed but the arrangement of the disk was lose;and the microvilli appeared of the disk was lose;and the microvilli appeared at the tip of RPE.The Activity of CCO and Mg ++ -ATPase decreased and MDA increased in retina at the 6th hour and on the 6th day and they recovered on the 14th day after light exposure. Conclusion：Lipd peroxidation that broke the cell membrane system of photoreceptor which induced changes of the cell ultrastru cture abd the activity of enzyme might relate to pathogenesis in retinal photochemical damage. (Chin J Ocul Fundus Dis,1998,14:38-40)
【摘要】 目的 探討抗氧化應激是否參與參附注射液預處理誘導的腎臟保護作用。 方法 健康成年雄性SD大鼠21只隨機分為假手術對照組（Sham組）、腎臟缺血再灌注組（I/R組）和參附注射液組（SF組）；SF組給予參附注射液10 mL/kg腹腔注射，每日1次，連續給藥7d。麻醉下行右腎切除后，用無損傷動脈夾鉗夾左側腎蒂60min，再灌注24 h，制備腎缺血再灌注損傷動物模型。比較各組SD大鼠再灌注24 h腎臟組織中超氧化物歧化酶（superonidedismutase，SOD）水平、過氧化氫酶（catalese，CAT）和丙二醛（malonicalaldehyed，MDA）含量。 結果 與Sham組相比，I/R和SF組腎臟組織SOD和CAT顯著降低，而MDA明顯升高（Plt;0.05）；與I/R組比，參附注射液能明顯增加SOD和CAT水平（Plt;0.05），降低MDA含量（Plt;0.05）。 結論 參附注射液預處理可增強缺血再灌注損傷腎臟組織抗氧化應激，其表現為增強SOD和CAT的活力，減少MDA的生成。【Abstract】 Objective To explore the protective effect of Shenfu injection combined with antioxidant system on rats’ kidney after ischemia-reperfusion injury. Methods Twenty-one male Sprague Dawley (SD) rats were randomly divided into 3 groups: sham operation group (Sham group), ischemia-reperfusion group (IR group), and shenfu injection treated group (SF group). The rats were anesthetized with valebarbitone. Bilateral kidneys were exposed through midline incision. The right kidney underwent the nephrectomy and left renal pedicels were occluded for 60 minutes with a traumatic mini-clamp and then unclamped for 24 hours. Animals in SF group received Shenfu injection (10 mL/kg) through intraperitoneal injection every day for 7 days. About 24 hours after reperfusion, superoxide dismutase (SOD), CAT and malonical aldehyde (MDA) were measured. Results The levels of MDA were lower in SF group than those in IR group (Plt;0.05). The level of SOD and CAT in SF group increased more significantly than which did in IR group (Plt;0.05). Conclusion Our finding suggests that antioxidant system in SF group works more efficiently than IR group to overcome oxidative stress in renal ischemia-reperfusion injury.
【Abstract】 Objective To investigate the protective role of recombinant human growth hormone (rhGH )in ischemic reperfusion injury of rat liver and its mechanism. Methods One hundred Male rats were randomly divided into two groups: the rhGH group and the control group. In the rhGH group, rhGH were injected （0.2U/100g weight） to rats seven days before the ischemic reperfusion injury, and in the control group, normal saline was injected instead. Serum levels of ALT， TNF-α and IL-1α were tested. Hepatic tissue was sectioned for to detect the level of EC and MDA, the expression of NF-κB and ICAM-1 mRNA on SEC. Ultrastructural characteristics histopathological characteristics were determined also. Results Serum levels of ALT, TNF-α, IL-1α and the contents of MDA in the control group were significantly higher than those in the rhGH group （P＜0.05）. Comparied with control group, rhGH also decreased NF-κB activation, and reduced the expression of ICAM-1 mRNA of SEC in the liver cells （P＜0.05）. Electronic microscopic revealed that the hepatic sinusoidal endothelial cells and the hepatocellular mitochondria were injured in the control group. Pretreatment with the rhGH was able to significantly improved the pathological changes. Conclusion rhGH might confer the protection to ischemic reperfusion injury of rat liver through reducing the expression of NF-κB to down-regulate cytokine (IL-1α,TNF-α), MDA and inhibition the expression of ICAM-1 mRNA.
Objective To study the effect of various doses of estrogen on tissue injury, blood supply and survival area of skin flap and to investigate its mechanism. Methods Thirty New Zealand white rabbits aged 3-4 months old and weighing 1.5-2.2 kg (male or female) were used. Random pattern skin flap (12 cm × 3 cm in size) taking the central l ine of the rabbit dorsum as axis and with the pedicle attached at the proximal end was prepared, and the flap pedicle division was performed 7 days after operation. The rabbits were divided randomly into three groups (n=10 rabbits per group). At 2, 4, and 6 days after operation, the proximal edge of flap in group A and B received 100 ?g/kg and 50 ?g/kg subcutaneous injection ofestradiol benzoate, respectively, while group C received no further treatment serving as control group. General condition ofthe rabbits was observed after injection, gross observation was performed 3 and 7 days after injection, survival area of the skin flap was measured 7 days after injection, contents of malondialdehyde (MDA) and nitric oxide (NO) were tested 5 days after injection, and the flaps were harvested 4 and 7 days after injection to receive histology and no significant difference was noted between group A and group B (P gt; 0.05). The NEU counts 4 days after injection were (18.20 ±6.24) cells/HP in group A, (21.27 ± 5.34) cells/HP in group B, and (28.78 ± 7.92) cells/HP in group C, and at 7 days after injection, there were (15.16 ± 7.02) cells/HP in group A, (18.12 ± 6.44) cells/HP in group B, and (29.67 ± 9.12) cells/HP in group C. The VEGF score 4 days after injection was (4.02 ± 0.48) points in group A, (4.19 ± 0.66) points in group B and (3.67 ± 0.49) points in group C, and at 7 day after injection, it was (4.96 ± 0.69) points in group A, (5.12 ± 0.77) points in group B, and (3.81 ± 0.54) points in group C. Significant difference was evident between 4 days and 7 days after injection in group A or B in terms of NEU counts and VEGF score (P lt; 0.05), and difference between 4 days and 7 days after injection in group C was not significant (P gt; 0.05), and the differences among 3 groups were significant (P lt; 0.05). Conclusion Estrogen injection can increase VEGF expression and NO content of flap, decrease MDA content and NEU infiltration of flat, and improve survival area of flap.
