[Effect of dexmedetomidine on renal injury induced by lung ischemia/reperfusion in mice].

OBJECTIVE: To evaluate the effect of dexmedetomidine(Dex) on renal injury induced by lung ischemia/reperfusion(I/R) in mice. METHODS: Fifty healthy SPF male C57BL/6J mice, weighing 20 g~24 g,aged 8~10 weeks,were randomly divided into five groups(n=10 each):sham operation group(sham group),lung ischemia/reperfusion group(I/R group), lung ischemia/reperfusion and normal saline group (NS group), dexmedetomidine group(Dex group), dexmedetomidine and atipamezole group (DA group). Lung ischemia/reperfusion model was established by occlusion of the left pulmonary artery for 30 min followed by 180 min reperfusion in mice. In Dex and DA groups, dexmedetomidine 20 µg/kg and dexmedetomidine 20 µg/kg plus atipamezole 250 µg/kg were injected intraperitoneally respectively at 30 min before establishment of the model, isopyknic normal saline instead of Dex were injected intraperitoneally in NS group. After the experiment the mice were killed and plasma IL-1 beta and tumor necrosis factor α(TNF-α) concentration were detected by ELISA; the renal tissues were harvested to observe ultra structure under electron microscope. RESULTS: Compared with sham group, the concentrations of IL-1ß and TNF-α in other groups were increased significantly and the structure damages of renal tissues observed under electron microscope in other groups were more serious than those of sham group. Compared with I/R group, NS groups and DA group, the concentrations of IL-1ß and TNF-α in Dex group were significantly lower(P<0.05)and the structure damages of renal tissues observed under electron microscope in Dex group were slighter. CONCLUSIONS: Dexmedetomidine pretreatment can attenuate renal injury induced by lung ischemia/reperfusion and the mechanism may be related to inhibition of inflammatory responses.

[Protective effects and mechanism of SP600125 on lung ischemia/reperfusion injury in rats].

OBJECTIVE: To investigate the protective effects and mechanism of SP600125-specificity inhibitor of c-Jun N-terminal kinase (JNK)on lung ischemia /reperfusion injury in rats. METHODS: The unilateral lung ischemia/reperfusion model was replicated in vivo. Rats were randomly divided into three groups (n = 10): control group, ischemia/reperfusion group ( I/R group) and ischemia/reperfusion + SP600125 group (SP600125 group). The lung tissues sampled at the end of each experiment were assayed for wet/dry weight ratio (W/D),the injured alveoli rate (IAR), the expression of phosphorylation JNK (p-JNK) and JNK protein were detected by Western blot, the expression of Bcl-2, Bax, Caspase3 protein were detected by immunocytochemistry techniques, the pneumocyte apoptosis index (AI) was detected by terminal deoxynucleotidyl transferase mediated dUTP nick end abeling(TUNEL), the ultrastructure changes were observed under electron microscope. RESULTS: Compared to I/R group, the expression of p-JNK, Bcl-2, Bax and caspase-3 protein were markedly decreased (all P < 0.01), the expression of Bcl-2 protein and the ratio of Bcl-2/Bax were markedly increased in SP600125 group(all P < 0.01). The value of AI, W/D, IAR showed significantly lower than those in I/R group (all P <0.01). Meanwhile, light morphological and ultrastructure injury were found in SP600125 group. CONCLUSION: SP600125 can suppress JNK signal pathway, up-regulate the ratio of Bcl-2/Bax to inhibit Caspase-3 dependent apoptosis, so that it protects lung tissue from ischemia/reperfusion injury.

[Effects of Panax notoginseng saponins on pneumocyte apoptosis and c-Jun N-terminal kinase in lung ischemia/reperfusion injury].

The aim of the present study is to investigate the effects of Panax notoginseng saponins (PNS) on pneumocyte apoptosis and apoptosis-related protein, as well as c-Jun N-terminal kinase (JNK) in lung ischemia/reperfusion (I/R) injury. Thirty Wistar rats were randomly divided into control group, I/R group and PNS group. The unilateral lung I/R model was replicated by obstruction of left lung hilus for 30 min and reperfusion for 120 min in vivo. The rats in PNS group were given intraperitoneal injection of PNS at 60 min before ischemia and 10 min before reperfusion. Some lung tissues sampled at the end of the experiment were assayed for wet/dry weight ratio (W/T). The expressions of phosphorylated JNK (p-JNK) and JNK protein were detected by Western blot. The expressions of Bcl-2, Bax and Caspase-3 protein were detected by immunocytochemistry techniques. The pneumocyte apoptotic index (AI) was detected by terminal deoxynuleotidy1 transferase mediated dUTP nick end labeling (TUNEL). The morphological and ultrastructure changes were observed under light microscope and electron microscope, and the injured alveolus rate (IAR) was counted as well. The results showed that compared to control group, I/R group showed increased expressions of p-JNK, Bcl-2, Bax and Caspase-3 protein (all P < 0.01), decreased ratio of Bcl-2/Bax (P < 0.05), and increased values of AI, W/T and IAR (all P < 0.01). Moreover, light microscope and electron microscope showed serious morphological and ultrastructure injury in I/R group. Compared to I/R group, PNS group showed markedly decreased expressions of p-JNK, Bax and Caspase-3 protein (all P < 0.01), increased expression of Bcl-2 protein and ratio of Bcl-2/Bax (both P < 0.01), and lower values of AI, W/T and IAR (all P < 0.01). Meanwhile, light morphological and ultrastructure injury was found to be alleviated in PNS group. These results suggest that PNS can protect lung tissue from I/R injury, and the mechanism may correlate with suppressing JNK signal pathway, up-regulating the ratio of Bcl-2/Bax which results in inhibition of Caspase-3 dependent apoptosis.

[Effect of Safflor injection on the intestine ultrastructure characteristics following intestine ischemia/reperfusion injury in rabbits].

AIM: To explore effects of Safflor (Chinese Tradional Medicine) on the intestine ultrastructure characteristics during intestine ischemia/ reperfusion injury (I/RI) in rabbits. METHODS: Thirty rabbits were randomly divided into three groups: control group (group S), ischemia/reperfusion group (group I/R) and Safflor injection group (group SI). Morphological changes of intestine ischemia/reperfusion in rabbits and the protective effects of Safflor were observed under electric telescope. RESULTS: The intestine ultrastructure was badly injured in group I/R. Mitochondria and intestinal mucosal cells were swellen and endoplasmic reticulum expanded, however, in the SI group the ultrastructural injury of the ischemia greatly ameliorated. CONCLUSION: The ultrastructure injury occurrted after intestine I/RI and Safflor has protective effects on the intestine ultrastructure.

[Clinical application and long-term follow-up study of acellular dermal matrix combined with auto-skin grafting].

OBJECTIVE: To investigate the clinical effect of acellular dermal matrix (ADM) combined with auto-skin grafting on deep burn wound ,and the result of long-term follow-up and histological examination. METHODS: One hundred and fifty-two patients with deep burn hospitalized from February 2000 to July 2003 were repaired with porcine ADM and auto split-thickness graft. Wound healing rate was assessed 1 week after operation. Degree of cicatricial hyperplasia was examined 1, 3, 6, 12 months after operation. Wound samples from 5 patients were harvested for histological examination 72 months after operation, for which transmission electron microscopy were employed in 2 cases. RESULTS: Grafts completely survived was seen in 116 patients (accounting for 76.3% of cases), survival rate over 95% were observed in 23.7% of cases. One hundred and twenty-seven patients were followed up 1 month after operation, in whom mild local contraction, cord like scar was seen along its junction with skin, its texture was soft ,and there was no pruritus or blister formation. One hundred and one patients were followed up 3 months after operation, and the graft showed mild contraction less marked when compared with that of the site where auto split-thickness skin grafting was used. Articular function was good. Eighty-two patients were followed up 6 months after operation,color and texture of grafts were similar to normal skin with no obvious cicatricial hyperplasia. Fifty-eight patients were followed up 12 months after operation, the texture of grafts was similar to normal skin without obvious reject reaction. Sixteen patients were followed up over 72 months after operation, the grafts appeared dry compared with normal skin. Histological examination showed: tissue structure of grafts was similar to normal skin, intact small sweat gland and sweat gland cells were not found in dermal layer. CONCLUSION: Heterologous ADM combined with auto split-thickness graft can survive in human body without obvious immune rejection reaction for a long time. No intact small sweat gland or sweat gland cells in dermis is a problem worth of study in regeneration of skin function.

[Ginkgo biloba extract enhances testosterone synthesis of Leydig cells in type 2 diabetic rats].

OBJECTIVE: To investigate the effects of Ginkgo biloba extract (EGB) on the testosterone synthesis in the Leydig cells of type 2 diabetic rats. METHODS: Thirty male SD rats were equally randomised into a normal control, a type 2 diabetic and an EGB group. Morphological changes of Leydig cells were observed by light microscopy (LM) and transmission electron microscopy (TEM), concentrations of serum luteinizing hormone (LH) and testosterone (T) were determined by enzyme linked immunosorbent assay (ELISA), and the mRNA levels in the steroidogenic acute regulatory protein (StAR), cytochrome P450 side chain cleavage (P450scc), cytochrome P450 17a-hydroxylase (P450c17), 17beta-hydroxysteroid dehydrogenase 3 (17beta-HSD3) and 3beta-hydroxysteroid dehydrogenase (3beta-HSD1) from the Leydig cells were examined by RT-PCR. RESULTS: Compared with the normal control, there was a significant decrease in the number and volume of Leydig cells, the levels of serum LH and T and the expression of mRNA in StAR, P450scc, 17beta-HSD3 and 3beta-HSD1 in the type 2 diabetes group. And the expression of the P450c17 gene showed a tendency of descending, but with no significance. Compared with the type 2 diabetes group, 12 weeks of EGB treatment caused very slight pathological changes in the Leydig cells, significantly increased the concentrations of blood LH and T, markedly elevated the levels of mRNA in StAR and P450scc and induced an ascending tendency of the expressions of P450c17, 17beta-HSD3 and 3beta-HSD1. CONCLUSION: EGB enhances testosterone synthesis and secretion of Leydig cells by reducing the impairment of the testis in type 2 diabetic rats.

[Effect of ligustrazine on expression of Fas/FasL in pulmonary injury induced by ischemia/reperfusion in rabbits].

AIM: To investigate the effect of ligustrazine (LGT) on expression of Fas/FasL mRNA during pulmonary ischemia/reperfusion injury (PI/RI) in the rabbits. METHODS: Single lung ischemia/reperfusion animal model was used in this study. The rabbits were randomly divided into three groups (n = 30, in each): sham operated group (Sham), I/R group (I/R) and I/R + LGT group (I/R + LGT). Changes of several parameters which included apoptotic index (AI), wet to dry ratio of lung tissue weight (W/D) and index of quantitative assessment of histologic lung injury (IQA) were measured at 1h, 3h, 5h after reperfusion in lung tissue. Meanwhile the location and expression of Fas/FasL mRNA were observed. Lung tissue was prepared for light microscopic and electron microscopic ob servation at 1 h, 3 h, 5 h after reperfusion. RESULTS: As compared with group I/R, Fas/FasL mRNA slightly expressed in intima and extima of small pulmonary artery, alveoli, and bronchiole epithelia in group LGT. The values of AI, W/D and IQA showed significantly lower in group I/R + LGT than that in group I/R at 1 h, 3 h, 5 h after reperfusion in lung tissue (P < 0.01 and P < 0.05). Meanwhile, abnormal changes of the lung tissue in morphologically were lessen markedly in group I/R + LGT. CONCLUSION: Ligustrazine has notable protective effects on PI/RI in rabbits by inhibiting Fas/FasL mRNA express in lung tissue and decreasing apoptosis.

[Effect of ligustrazine and L-arginine on function of mitochondria in myocardium after ischemia/reperfusion injury of myocardium in rabbits].

AIM: To study the effect of ligustrazine (LGT) and L-arginine(L-Arg)on function of mitochondria in myocardium after myocardial ischemia/reperfusion injury (MI/RI). METHODS: 50 rabbits were randomly divided into five groups (n=10): Control group(A), MI/R group(B), MI/R + LGT group (C), MI/R+ L-Arg group (D), MI/R+ LGT + L-Arg group (E). The mitochondrial respiratory function, Ca2+ concentration ([Ca2+]m), malondialdehyde (MDA) content and superoxide dismutase (SOD) activity were deter mined. Meanwhile, the contents of ATP and EC in the myocardial tissue were measured, respectively. RESULTS: It was found that mitochondrial respiratory control rate (RCR), state 3 (ST3), SOD in C, D, E group were higher than those of B group, state 4 (ST4), [Ca2+]m, MDA were lower than those of B group, ATP and EC levels of myocardial tissue were higher than those in B group; and there were not significant differences between E and A group of above. CONCLUSION: LGT and IL-Arg can improve function of mitochondria in myocardium after ischemia/reperfusion injury of myocardium in rabbits by decreasing oxygen free radical level and Ca" overload in the mitochondria.

[DNA damage, Bcl-2, Bax expression and ultrastructure change in spermatogenic cell of mice exposed to cadmium].

OBJECTIVE: To study DNA damage, Bcl-2 and Bax expression, and ultrastructure change in spermatogenic cell of mice by cadmium exposure. METHODS: Twenty-four male mice were divided into 4 groups: 3 groups treated with cadmium chloride of 1, 5, 10 micromol x kg(-1) x d(-1) i.p. respectively for 5 days, and one normal saline control group. The DNA damage of spermatogenic cell by single-cell gel electrophoresis technology was detected. The expression positive rate of Bcl-2, Bax protein in spermatogenic cell by the immunohistochemical method was assayed, and the ultrastructural change of spermatogenic cell by the transmission electron microscope was observed. RESULTS: DNA damage rates of of spermatogenic cell in 1, 5, 10 micromol/kg cadmium chloride groups were higher than that of normal group (P < 0.001). Bcl-2 protein expression positive rates were lower than that of normal group (P < 0.001). Bax protein positive expression rate in 5 micromol/kg group was higher than those in normal group, and 1, 10 micromol/kg groups. The ultrastructure of karyotis, karyotheca, mitochondria, endoplasmic reticulum in three treated groups had different degree of damage and the degree of ultrastructural change was increasing with rising concentration of cadmium. CONCLUSION: Cadmium exposure will cause the DNA break, Bcl-2 and Bax protein abnormal expression and ultrastructural change in spermatogenic cell.

[Alveolar damage of pneumocystis carinii pneumonia in renal transplantation recipients].

OBJECTIVE: To study the alveolar ultrastructural changes and the interaction between Pneumocystis carinii (PC) and alveoli in Pneumocystis carinii pneumonia (PCP) patients after renal transplantation. METHODS: Twenty-seven patients with suspected PCP after renal transplantation were examinated by bronchoscopy with bronchoalveolar lavage (BAL) and transbronchial lung biopsy (TBLB). The BAL fluid was centrifuged and the sediments were stained for PC. Cases for which electron microscope showed alveolar tissue in TBLB specimen were included. Then the clinical features, PC, alveolar epithelial damage, exudate in alveolar space, inflammatory cell infiltration, and fibrous tissue in the interstitial space were analyzed and evaluated. RESULTS: Twenty-three cases were studied. The mean time from renal transplantation to onset of illness was 5.6 months, and that from onset of illness to hospitalization was 5.5 days. Clinical features included fever, dyspnea, unproductive cough, and scanty chest signs, to hypoxemic respiratory failure. Chest CT showed diffuse lung interstitial changes in 22 of the 23 cases, 9 with consolidation. After treatment with SMZco, the fever resolved in 1 - 5 days, and the general state of the patients became better, and 19 patients were dischaged within 1 month. PC in BAL fluid was found by special staining in 18 patients, while PC was found by electron microscope in 14 patients. In most cases PC was few in the lung tissue, but in 3 cases abundant PC filled the alveolar space. PC was seen in two forms, the cyst and the trophozoite. Electron and light microscopes showed alveolar exudate, inflammation in interstitium and alveolar space, interstitial fibrosis, and alveolar epithelial damage in all patients. CONCLUSION: In PCP patients after renal transplantation there was marked alveolar damage, which was the major pathological change in the lung.