| Objective:Studies in the recent years on the overtraining-induced acutekidney injury (OTIAKI) are constantly increasing, which is chiefly due to thefact that OTIAKI has become one of the major malignant diseases detrimentalto human health. The effective prevention and treatment methods, however,are absent primarily for the not explicit pathological mechanisms and injurypathways. Heat shock proteins (HSPs) are biological marker and anendogenous protective protein of cell stress response. The extent of cell injuryis related to the exprssion intensity of HSPs. Heat Shock Protein70(HSP70)is one of the HSPs with a highest content in cells, a most vulnerability toinductions and numerous biological functions. HSP70will significantlyincreases after stress and definitely has endogenous protective effects on cells.In this research, the OTIAKI animal model was established using rats withonce exhaustive swimming with no burden. The expression pattern of renaltissue HSP70and influences of anisodamine on the expression of HSP70wereobserved in exhaustive rats.Methods:(1)48healthy SD rats, weighing180-220g. The rats wererandomly divided into three groups: control group (CN, n=8), exhaustiveswimming group(ES, n=24) and Anisodamine group (AD, n=16).Exhaustive exercises were not applied to Sedentary control group (CN), andno drugs were injected; exhaustive group (ES) was then divided into threesub-groups (immediately group, ESI;6h group, ES6h;24h group, ES24)with respect to the restoration time after exhaustive exercises. Rats in eachsub-group were abdominally administered with a single injection of sterilewater for injection (10mg/Kg)20min before exercises; according torestoration time after exhaustive exercises, rats in the anisodamineintervention group with a single ip injection of anisodamine(10mg/Kg) before exhaustive exercises were also divided into two sub-groups: anisodamine6h(AD6h) and24h (AD24h) groups. Each sub-group had8individuals. Theovertraining-induced acute kidney injury (OTIAKI) animal model wasestablished using rats with once exhaustive swimming with no burden.(2)Thetwo kidneys were sampled after anaesthesia using intraperitoneal injection of5%Chloral Hydrate (3ml/kg). The left kidney was left in an EP tube withliquid-nitrogen inside and then the tube with sample was store at-80℃fordetection of HSP70expressed using Western blot. The right kidney wasmainly used for fixing tissue and paraffin section and placed in4%paraformof4℃for storage.(3) The renal histopathology change were observed withlight microscope in HE staining.(4)The expression of HSP70were detected byimmunohistochemistry.And the results were analyzed with the pathologicalimage analysis system.(5)The expression of HSP70were detected by westernblot analysis.(6) Statistical analysis: All statistical analysis of the experimentaldata were used SPSS13.0statistical software package, the results wereexpressed as mean±standard deviation(X±S).Differences are comparedusing single factor analysis of variance (one-way ANOVA), the P<0.05wasconsidered statistically significant.Results:(1)Rats after once exhaustive swimming with no burdenexhibited extreme fatigue with dim eyes, slouch, obtuse reaction to the outerstimulation, lying flat on the belly, standing instability, difficulty in activitiesand even bleeding in the bulbar conjunctiva in some severe ones. Two hoursafter exhaustive exercise, the rats in exhaustive group could move freely butthey usually exhibited poor state in eating and drinking. The rats inanisodamine group, however, could move freely and take normal diet only20min after exhaustive swimming.(2) No obvious changes in renal tissuestructure were detected in CN group and some light changes, such asdilatation of glomerular capsule and renal tubules, edema of renal proximaltubular epithelial cells and vacuolar degeneration, were found in ESI groupand ES6h group. However, rats with significantly changed renal tissuestructure were found in ES24h group. These changes including numerous darkly stained cells and cell pyknosis in medulla and the juncture of cortexand medulla, infiltrating cells in interstitium and the irregular or evendeciduous brush border observed in renal tubular epithelial cells. The rats inAD6h group and AD24h group showed significantly slight in structurechanges when compared to the corresponding sub-group of exhaustivegroup.(3) Immunohistochemistry staining reveals that most positive cells wererenal tubular epithelial nephric cells and no positive ones were found inglomerulus, the changes in renal medulla were more obvious than that incortex.Expression level of HSP70of rats in ES group was significantly higher(P<0.05) than that of normal control group.The expression of renal tissueHSP70in AD group was significantly higher (P<0.05) than ES group.(4)Western blot was performed to identify the HSP70expressed, which showedthat the expressed HSP70significantly increased (P<0.05) in ESI,ES6h andES24h compared to the control rats under the condition of basically identicalexpression of internal reference (GAPDH). The expression of renal tissueHSP70in AD groups was more obvious than that of ES groups (P<0.05).Conclusions:(1) HSP70expressed in renal tissue of exhaustive rats washigher than normal rats and the expression level showed an increasing trendwith the prolonged restoration time (0h,6h, and24h). Immunohistochemistrystaining reveals that the expression of HSP70in renal medulla was moreobvious than that in cortex.(2)The renal tissue injuries in exhaustive groupobserved in this study were more obvious than that in anisodamineintervention group with a higher expression level of HSP70, whichpresumably presents a relationship between protective effects of anisodamineon OTIAKI and the increasingly induced HSP70expressed in renal tissue. |
PDF Full Text Request