Abstract: Objective To investigate the localization G protein couple receptor 30 (GPR30) and its mRNA in submaxillary gland, and to supply theoretic evidence for further studying functional significance of the GPR30 in submaxillary gland of rats. Methods Four male SD rats were sacrificed by cervical dislocation after the intraperitoneal anesthesia, and excised the submaxillary glands. The distribution of GPR30 and its mRNA were studied through immunohistochemistry and in situ hybridization in the experiment. After isolation of the total RNA from the submaxillary gland, RT-PCR was conducted to obtain GPR30 cDNA by using the specific primers. The products of PCR were analyzed by sequencing with Sanger’s method. Results The serous acinus epithelial cells and granular convoluted epithelial cells in submaxillary gland of rats showed GPR30 immunoreactivity, which were located in cytoplasm with negative nuclei. GPR30 mRNA hybridized signals were also detected in cytoplasm in the above cells. The products of PCR is identical to that of the GPR30 sequence of rats. Conclusion The serous acinus and granular convoluted epithelial cells not only express GPR30 but also may be a target organ by rapid estrogen signaling pathway in submaxillary gland of rats. This may be involved in the functional regulation of submaxillary gland.

Key words: Estrogen receptor, G protein couple receptor 30, Submaxillary gland, Immunohistochemistry, In situ hybridization, RT-PCR, Rat