糖尿病大鼠肾脏纤维化病理检测和超声背向散射积分参数的相关性研究

目的探讨大鼠糖尿病模型肾脏纤维化的病理改变与肾脏背向散射积分（IBS）参数变化的关系,继而评价超声背向散射积分技术与传统病理检测结果的相关性。旨在为应用超声背向散射积分技术测量糖尿病肾脏纤维化提供实验依据。方法腹腔注射链脲佐菌素（STZ）诱导糖尿病大鼠模型。分别于实验4、12、24周测量糖尿病模型组及空白对照组的大鼠肾脏背向散射积分参数。同一时间,为两组进行大鼠肾脏病理检测。比较两种测量方法的对纤维化测量的结果。结果 1）肾脏纤维化各指标的变化：测量糖尿病组的系膜基质指数（Ms/Gs）（4周0.25±0.02,12周0.47±0.05,24周0.56±0.04）;肾小球胶原沉积评分（GCDS）（4周0.34±0.03,12周0.49±0.03,24周0.62±0.06）;血管周围胶原面积（PVCA）（4周0.96±0.11,12周1.65±0.18,24周2.63±0.40）;肾小管间质病变评分（TILS）（4周1.5,12周3,24周4.5）于三个时间段,皆显著高于同周龄健康对照组,差异有统计学意义（各为P〈0.05）,且随病程进展,逐渐增高（各为P〈0.05）。2）超声指标结果：糖尿病各组大鼠肾脏皮质IBS%（4周0.51±0.04,12周0.73±0.05,24周0.95±0.11）与髓质IBS%（4周0.31±0.07,12周0.58±0.03,24周0.87±0.12）于三个时间段,皆明显高于同周龄对照组（各为P〈0.05）,且随着病程进展逐渐增高（各为P〈0.05）。3）超声背向散射积分技术与糖尿病肾病纤维化各指数的相关性：肾皮质IBS%与GCDS（r=0.95）、PVCA（r=0.89）、TILS（r=0.85）、Ms/Gs（0.89）（P〈0.05）;并且肾髓质IBS%与GCDS（r=0.94）、PVCA（r=0.91）、TILS（r=0.83）、Ms/Gs（0.90）（P〈0.05）呈正相关。结论传统病理学方法可检测到糖尿病大鼠肾脏纤维化病理改变,以及各指标（GCDS、PVCA、TILS、Ms/Gs）在肾脏的表达增加;应用IBS技术可检测到,随着病程进展,肾皮质、肾髓质IBS%也都增高,提示超声背向散射积分（IBS）技术与传统病理学检验手段相关,IBS技术可能成为评价肾脏纤维化的重要方法。

Association between Histopathology and Integrated Backscatter in Diabetic nephropathy rats

Objective To explore association between histopathology and integrated backscatter in diabetic nephropathy rats. Methods The diabetic rats model was built by using intraperitoneal injection of streptozotocin （STZ） to rats of the study group. At the end of 4, 12 and 24 weeks, we collected the data of renal integrated backscatter parameters in the diabetic rats （case group） and in the healthy rats （control group） respectively. Meanwhile, we took pathologic examinations to the renal tissues of the rats in both groups, respectively. Then, IBS parameters in two groups were compared in different time periods. Results Pathologic changes of each renal fibrosis parameter： we found that the results of the study group in glo- merular mesangial matrix index （Ms/Gs） （4wk 0.25 5： 0.02, 12wk 0.47 ± 0.05, 24wk 0.56 ± 0.04）, glomerular collagen deposition score （GCDS） （4wk 0.34 ±0.03,12wk 0.49 ± 0.03,24wk 0.62 ± 0.06）, perivascular collagen area （PVCA） （4wk 0.96 ± 0.11,12wk 1.65 ±0.18,24wk 2.63 ± 0.40）, tubular interstitial disease score （TIDS） （4wk 1.5, 12wk 3, 24wk 4.5 ） at three time points were significantly higher than each result of the control group （P〈0.05 respectively）. As the disease progresses, the results of each parameter increased （P〈0.05 respectively）. 2） Dynamic changes of renal integrated backscatter parameters： we found that the results of the study group in the IBS% of renal cortex （4wk 0.51 ± 0.04, 12wk 0.73 ± 0.05, 24wk 0.95 ±0.11 ） and the IB S% of renal medulla （4wk 0.31 ± 0.07, 12wk 0.58 ± 0.03, 24wk 0.87 ± 0.12 ） at three time points were significantly higher than each result of the control group （P〈0.05 respectively）. As the disease progresses, the results of each parameter increased （P〈0.05 respec-tively）.3） The associations between IBS%s and each renal fibrosis parameter： we found that the IBS% of renal cortex was linearly associated with GCDS （r=0.95）. PVCA （r=0.89）, TILS （r=0.85）, Ms/Gs （0.89） （P〈0.05 respectively）, and the IBS% of renal medulla was also linearly associated with GCDS （r=0.94）, PVCA （r=0.91）. TILS （r=0.83）. Ms/Gs （0.90） （P〈0.05 respectively） . Conclusions Using classic histo- pathological examination technologies detected renal fibrosis in STZ-induced diabetic rats and found each fibrosis index （PVCA, GCDS, TILS and Ms/Gs） increased respectively. Meanwhile, using renal integrated backscatter detected IBS%s of renal cortex and renal medulla increased respectively as the disease progressed. There is a positive association between IBS%s and fibrosis indices （PVCA, GCDS, TILS and Ms/Gs） ,demonstrating that the results of histopathological examination were linearly associated with that of IBS technology. Thus, IBS technology can become the important estimated method to renal fibrosis in diabetic nephropathy.