Predominant expression of the src homology 2-containing tyrosine phosphatase protein SHP2 in vascular smooth muscle cells

src homology 2 (SH2)-containing protein-tyrosine phosphatase SHP2 is known to transduce positive signals from activated receptor protein-tyrosine kinases such as platelet-derived growth factor receptor (PDGFR) beta and insulin receptor. Here, we demonstrate the physiological expression of SHP2 in rats. In northern and west ern blot analyses, SHP2 expressions were recognized in all tissues, but their expression levels varied significantly among tissues; it is lowest in the liver and kidney. Immunohistochemical staining and in situ hybridization showed SHP2 was expressed ubiquitously but predominantly in vascular smooth muscle cells (SMC). During the development of granulations, SHP2 was expressed predominantly in vascular SMC and also highly expressed in capillary cells. The functional associations of SHP2 with PDGFR beta, which transduces major growth signals in vascular SMC, identify a crucial function of SHP2 in blood vessels in consert with PDGFR beta.