Changes in protein tyrosine phosphatase activity in Spontaneously Diabetic Torii (SDT) rats

Takayuki Yamaguchi, akeshi Ohta, Hisayo Morinaga, Takahiro Hata, Eimei Sato, Mutsuyoshi Matsushita

Biological/Pharmacological Research Laboratories, Central Pharmaceutical Research Institute, Japan Tobacco Inc., Osaka, Japan.
Laboratory of Animal Reproduction, Graduate School of Agricultural Science, Tohoku University, Sendai, Japan.

DOI: 10.4236/ojas.2012.24035                

Abstract

The Spontaneously Diabetic Torii (SDT) rat is a nonobese type 2 diabetic model, showing the overt hyperglycemia after about 16 weeks of age. In this study, we investigated the protein tyrosine phosphatase (PTPase) activities in insulin-sensitive tissues in SDT rats. PTPase activities in the liver, muscle, and fat were examined at 8 weeks (pre-diabetes), 16 weeks (onset-diabetes), and 24 weeks (diabetes). SDT rats showed glucose intolerance at 8 weeks and hyperglycemia after 16 weeks. The PTPase activities in fat increased at 8 weeks and the increase was sustained to 24 weeks. In the liver, PTPase activities increased only at 24 weeks. On the other hand, the PTPase activities in muscle did not change. The increase of PTPase activity in fat might be related to progression of glucose intolerance and diabetes in SDT rats.

Keywords

Fat; PTPase; SDT Rat

Conflicts of Interest

The authors declare no conflicts of interest.

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