Abstract: Objective To study the role of galanin and its receptors on cell vitality and invasion in rat pituitary adenoma cells. Methods Rat pituitary GH3 cells RNA was extracted to determine the expression levels of galanin and its receptors with RT-PCR; Matrigel-coated Transwell chamber was used to quantify invasiveness of rat pituitary GH3 cells in the presence or absence of galanin or GalR2 agonist AR-M1896. The effect of galanin or GalR2 agonist AR-M1896 on the cell vitality was determine by MTT assay. Results Expression of galanin and all three galanin receptor subtypes were detected in the rat pituitary GH3 cells and expression levels of GalR2 were particularly high. There is no significant difference in cell proliferation levels between the presence and absence of galanin or AR-M1896 at 12h, 24h, 36h. However, the cell invasion through Matrigel was decreased by approximately 49% in rat pituitary GH3 cells with galanin treatment(100nM) compared with control group (p<0.01). AR-M1986 (100 nM) also showed a suppression of cell invasion of 46% (p< 0.05) compared with control group. There were no significant difference in suppression of cell invasion between AR-M1986 and galanin groups. Conclusion Galanin inhibits cell invasion, at least partially via GalR2, in rat pituitary adenoma cells.

Key words: invasive, galanin, GH3 cells