[關鍵詞]
[摘要]
目的 通過丙磺舒(PRB)抑制有機陰離子轉運蛋白(OAT)1和 3,觀察馬兜鈴酸Ⅰ(AAⅠ)對大鼠腎小管上皮細胞的急性損傷,以探究 AA Ⅰ進入腎小管上皮細胞的途徑 。方法 雄 性 SD 大 鼠 隨 機 分 為 空 白 對 照 組 、 溶 劑 對照 (PEG300) 組、PRB(150 mg · kg-1)組、AA(Ⅰ 80 mg·kg-1)組、AA(Ⅰ 80 mg·kg-1)+PRB(150 mg · kg-1)組,每 2天 ig給藥1次,連續(xù)給藥4次。觀察大鼠腎臟指數(shù);生化儀檢測血清肌酐(CREA)和尿素氮(BUN)水平;蘇木精-伊紅(HE)染色觀察腎臟組織病理學變化;免疫組化染色觀察 OAT1 和 OAT3 在腎小管的組織定位和蛋白表達水平;免疫透射電鏡觀察OAT1和 OAT3在腎小管上皮細胞的亞細胞定位和表達水平。結果 與溶劑對照組相比,AAⅠ組腎臟指數(shù)、CREA和 BUN水平顯著增加(P<0.01、0.001);AAⅠ+PRB組與AAⅠ組相比,腎臟指數(shù)、CREA和BUN水平顯著降低(P<0.05、0.001)。HE染色結果顯示,與溶劑對照組相比,AAⅠ組腎近端小管上皮細胞(PCTEC)出現(xiàn)空泡樣變性、微絨毛脫落以及片狀壞死脫落,而 AA Ⅰ+PRB 組與 AA Ⅰ組相比,PCTEC 空泡樣變性率下降,無其他類型病理學變化;另外,腎遠端小管上皮細胞(DCTEC)AAⅠ組與AAⅠ+PRB組呈現(xiàn)少量空泡樣變性。免疫組化和電鏡結果顯示,OAT1主要在PCTEC基底膜側表達,OAT3主要在 DCTEC 基底膜側表達,且 AAⅠ暴露后,與溶劑對照組比較,前者在近端小管(PCT)表達有下降趨勢(P<0.05),后者在遠端小管(DCT)表達有上升趨勢(P<0.05)。結論 AAⅠ能夠導致 PCT 和 DCT 的損傷,PRB 抑制 OAT1 和OAT3后,能夠改善腎臟功能,并減少腎小管上皮細胞的病理學損害;OAT1可能是AAⅠ進入PCTEC的主要通道,而OAT3則可能是其進入DCTEC的主要通道。
[Key word]
[Abstract]
Objective Utilizing probenecid (PRB) as an inhibitor of organic anion transporter (OAT) 1 and 3, to investigate the acute injury of renal tubular epithelial cells in rats induced by aristolochic acid I (AA Ⅰ) and elucidate the pathway through which AA Ⅰ enters renal tubular epithelial cells. Methods Male Sprague-Dawley rats were randomly assigned to five groups: the blank control group, the solvent control (PEG300) group, the PRB (150 mg·kg-1) group, the AAⅠ (80 mg·kg-1) group, and the AAⅠ+PRB (80 mg·kg-1 + 150 mg · kg-1) group. Administer ig once every two days for four consecutive doses. Observed the renal organ index of rats, and biochemical analyzer detected serum creatinine (CREA) and urea nitrogen (UREA) levels. Hematoxylin-eosin (HE) staining was employed to examine the pathological alterations in renal tissue. Immunohistochemical (IHC)staining was conducted to assess the tissue localization and protein expression levels of OAT1 and OAT3 in renal tubules. Immunoelectron microscopy was utilized to investigate the subcellular localization and expression levels of OAT1 and OAT3 in renal tubular epithelial cells. Results Compared with the solvent control group, the renal index, CREA, and BUN levels in the AA Ⅰ group were significantly increased (P <0.01, 0.001); Compared with the AAⅠ group, the renal index, CREA, and BUN levels were significantly reduced in the AA Ⅰ+PRB group (P <0.05, 0.001). HE staining revealed cellular edema, necrotic shedding, microvillous loss in proximal convoluted tubule epithelial cells (PCTEC) in the AAⅠgroup (P <0.05). Conversely, in the AAⅠ+PRB group, the incidence of vacuolar degeneration in PCTEC decreased significantly (P <0.05) without other observed pathological changes. Additionally, a minor degree of vacuolar degeneration was observed in distal convoluted tubule epithelial cells (DCTEC) in both the AA Ⅰand AA Ⅰ+PRB groups. IHC and electron microscopy revealed that OAT1 was predominantly expressed in the basolateral membrane of PCTEC, while OAT3 was primarily expressed in the basolateral membrane of DCTEC. Following exposure to AA Ⅰ, the expression of OAT1 exhibited a decreasing trend in the proximal convoluted tubule (PCT) (P <0.05), whereas the expression of OAT3 showed an increasing trend in the distal convoluted tubule (DCT) (P <0.05). Conclusion AA Ⅰ induces damage to both proximal convoluted tubules (PCT) and distal convoluted tubules (DCT), while PRB inhibiting OAT1 and OAT3 demonstrates improvement in renal function and reduction in pathological damage to renal tubular epithelial cells. These findings suggest that OAT1 may primarily facilitate the entry of AAⅠ into PCTEC, whereas OAT3 may serve as the primary route for its entry into DCTEC.
[中圖分類號]
R992
[基金項目]
國家自然科學基金資助項目(82160099);貴州省科技計劃項目(黔科合基礎-ZK[2021]一般 356);貴州省科技廳基礎研究計劃(黔科合基礎-ZK[2022]一般465)