title: The relationship between transforming growth factor beta1 expression and cold ischemia injury of rat donor kidney.
abstract: OBJECTIVE
  Cold ischemia injury represents an independent risk factor which favors chronic allograft nephropathy (CAN). In order to investigate the role of transforming growth factor-beta 1( (TGF-beta1) in the progression of CAN, we studied the relationship between the expression of TGF-beta1 and cold ischemia injury in the renal tubular epithelia of rat donor kidney.
  
  
  METHODS
  A total of 24 Wistar rats were used in this study. In terms of the time of cryopreservation of donor kidney, the 24 Wistar rats were randomly divided into 3 groups: 0 h group(control group), 24 h group, 48 h group. A block removal of donor kidney with in situ perfusion of cooling HC-A preservation solution was adopted. The rat kidney was preserved 0 h, 24h and 48 h at 0-4 degrees C respectively. The morphologic changes of proximal tubular epithelial cells in different cryopreservation time were observed under light microscope and transmission electron microscope. The expression of TGF-beta1 mRNA and protein in proximal tubular epithelial cells of different cryopreservation time group were detected by in situ hybridization and immunohistochemistry analysis.
  
  
  RESULTS
  1. In 24 h group, part of the proximal tubular epithelial cells showed slight degeneration. In 48 h group, the proximal tubular epithelial cells demonstrated severe hydropic degeneration and part of the cells developed necrosis and effluxion. 2. Only a small amount of TGF-beta1 protein and mRNA were expressed in the renal tubular epithelial cells of 0 h group. The positive unit (PU) value of TGF-beta1 protein and mRNA were 6.37+/-2.77 and 5.29+/-2.15, respectively. As the cold ischemia time prolonged, the PU value of TGF-beta1 protein increased at 24 h group (10.20+/-3.27) and 48 h group (17.17+/-3.96) . The PU value of TGF-beta1 mRNA also increased at 24 h group (11.31+/-3.34) and 48 h group (19.01+/-3.53). There was the significant difference of TGF-beta1 protein PU value or mRNA PU value among these groups(P<0.05).
  
  
  CONCLUSIONS
  There was the significant correlation between the expression of TGF-beta1 and the degree of cold ischemia injury. The results suggest that TGF-beta1 might play the key role in regeneration and reparation of renal tubular epithelial cell injury. The overexpression of TGF-beta1 might be one of the mechanisms that initiate chronic allograft nephropathy.
authors.affiliation: Morphological Experiment Center, Medical College, Jinan University, Guangzhou, Guangdong 510632, PR China.
authors.forename: Wenfang
authors.initials: W
authors.lastname: He
authors.forename: Kaishan
authors.initials: K
authors.lastname: Liu
authors.forename: Hongwen
authors.initials: H
authors.lastname: Ding
mesh_terms: D000818:Animals; D050377:Cold Ischemia; D015925:Cryopreservation; D051799:Delayed Graft Function / Q000209:etiology / Q000378:metabolism* / Q000473:pathology; D004195:Disease Models, Animal; D015870:Gene Expression; D017403:In Situ Hybridization; D007674:Kidney Diseases / Q000209:etiology / Q000378:metabolism* / Q000473:pathology; D016030:Kidney Transplantation / Q000009:adverse effects / Q000473:pathology / Q000502:physiology*; D007687:Kidney Tubules, Proximal / Q000378:metabolism* / Q000648:ultrastructure; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D013997:Time Factors; D014019:Tissue Donors; D053773:Transforming Growth Factor beta1 / Q000235:genetics / Q000378:metabolism*; D014184:Transplantation, Homologous
chemical_list: D012333:RNA, Messenger; D053773:Transforming Growth Factor beta1