Chonnam Med J.  2013 Dec;49(3):108-112. 10.4068/cmj.2013.49.3.108.

Increased Phosphorylation of PI3K/Akt/mTOR in the Obstructed Kidney of Rats with Unilateral Ureteral Obstruction

• Ma SK
• Joo SY
• Kim CS
• Choi JS
• Bae EH
• Lee J
• Kim SW

• KMID: 2048814
• DOI: http://doi.org/10.4068/cmj.2013.49.3.108

Abstract

The present study aimed to investigate changes in the mammalian target of rapamycin (mTOR) signaling pathway in the obstructed kidney of rats with unilateral ureteral obstruction (UUO). Male Sprague-Dawley rats were unilaterally obstructed by ligation of the left proximal ureter for 7 days. Control rats were treated in the same way except that no ligature was made. The expression levels of phosphorylated phosphatidylinositol 3-kinase (PI3K), Akt, and mTOR were determined in the kidney by semiquantitative immunoblotting. The protein expression levels of transforming growth factor (TGF)-beta1, Bax, and Bcl-2 were also determined in the kidney. The phosphorylation of PI3K, Akt, and mTOR was increased in the kidney of ureteral obstruction rats compared with the control. In the obstructed kidney, the protein expression of TGF-beta1 and Bax was also increased, whereas Bcl-2 expression was decreased. In conclusion, the phosphorylation of PI3K/Akt/mTOR was increased in the obstructed kidney of rats with UUO.

Keyword

mTOR protein, rat; Ureteral Obstruction; Fibrosis; Apoptosis

MeSH Terms

Animals
Apoptosis
Fibrosis
Humans
Immunoblotting
Kidney*
Ligation
Male
Phosphatidylinositol 3-Kinase
Phosphorylation*
Rats*
Rats, Sprague-Dawley
Sirolimus
Transforming Growth Factor beta1
Transforming Growth Factors
Ureter*
Ureteral Obstruction*
Phosphatidylinositol 3-Kinase
Sirolimus
Transforming Growth Factor beta1
Transforming Growth Factors

Figure

• 

  FIG. 1 The protein expression of phosphorylated phosphatidylinositol 3-kinase (p-PI3K) in the kidney. OSOM, outer stripe of the outer medulla; ISOM, inner stripe of the outer medulla; IM, inner medulla; UUO, unilateral ureteral obstruction. Each column represents the mean±SEM of 10 rats. *p<0.05 compared with control kidney.

• 

  FIG. 2 The protein expression of phosphorylated Akt (p-Akt) in the kidney. Legends as in Fig. 1.

• 

  FIG. 3 The protein expression of phosphorylated mammalian target of rapamycin (p-mTOR) in the kidney. Legends as in Fig. 1.

• 

  FIG. 4 The protein expression of transforming growth factor (TGF)-β1 in the kidney. Legends as in Fig. 1.

• 

  FIG. 5 The protein expression of Bax in the kidney. Legends as in Fig. 1.

• 

  FIG. 6 The protein expression of Bcl-2 in the kidney. Legends as in Fig. 1.

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