Mice deficient in protein tyrosine phosphatase receptor type Z (PTPRZ) show reduced responsivity to methamphetamine despite an enhanced response to novelty

Akihiro Fujikawa, Yukihiro Noda, Hideko Yamamoto, Naomi Tanga, Gaku Sakaguchi, Satoko Hattori, Wen Jie Song, Ichiro Sora, Toshitaka Nabeshima, Goro Katsuura, Masaharu Noda

研究成果: Article


Methamphetamine (METH), a commonly abused drug, elevates extracellular dopamine (DA) levels by inducing DA efflux through the DA transporter (DAT). Emerging evidence in rodent models suggests that locomotor responses to a novel inescapable open field may predict behavioral responses to abused drugs; METH produces more potent stimulant effects in high responders to novelty than in low responders. We herein found that mice deficient in protein tyrosine phosphatase receptor type Z (Ptprz-KO) exhibited an enhanced behavioral response to novelty; however, METH-induced hyperlocomotion was significantly lower in Ptprz-KO than in wild-type mice when METH was administered at a non-toxic dose of 1 mg per kg body weight (bdw). Single-cell RT-PCR revealed that the majority of midbrain DA neurons expressed PTPRZ. No histological alterations were observed in the mesolimbic or nigrostriatal dopaminergic pathways in Ptprz-KO brains; however, a significant decrease was noted in brain DA turnover, suggesting functional alterations. In vivo microdialysis experiments revealed that METH-evoked DA release in the nucleus accumbens was significantly lower in Ptprz-KO mice than in wild-type mice. Consistent with this result, Ptprz-KO mice showed significantly fewer cell surface DAT as well as weaker DA uptake activity in striatal synaptosomes prepared 1 hr after the administration of METH than wild-type mice, while no significant differences were observed in the two groups treated with saline. These results indicate that the high response phenotype of Ptprz-KO mice to novelty may not be simply attributed to hyper-dopaminergic activity, and that deficits in PTPRZ reduce the effects of METH by reducing DAT activity.

ジャーナルPloS one
出版物ステータスPublished - 01-01-2019


All Science Journal Classification (ASJC) codes

  • Biochemistry, Genetics and Molecular Biology(all)
  • Agricultural and Biological Sciences(all)
  • General