Figure 4.

Anxiety-related responses are similarly increased in A2AR-Gpr88 KO and total KO mice. A–D, A2AR-Gpr88 mice (A, B) and total KO mice (C, D) enter more frequently and spent more time in the light compartment of the light/dark test. E–J, In the elevated plus maze, Gpr88^A2A-Cre and Gpr88 ^−/− mice present higher open arms exploration ratios (E, H, respectively), more frequent total and distal head dips (F, I), and increased time spent in the distal zone of the open arms when compared with their control littermates (G, J). K–R, Social interactions were evaluated in a dimly lit open field with wild-type naive mice of the same age and gender. Both mutant animals display increased number of nose and paw contacts, as well as increased following behaviors. Gpr88^−/− mice, but not Gpr88^A2A-Cre mice, engaged less frequently in grooming episodes than control animals Data are presented as the mean ± SEM. A, B: n = 11, Gpr88^A2A-Cre; n = 9 Gpr88^flx/flx; C, D: n = 10, Gpr88 ^−/−; n = 11, Gpr88^+/+; E–G: n = 12, Gpr88^A2A-Cre; n = 13, Gpr88^flx/flx; H–J: n = 11, Gpr88 ^−/−; n = 9, Gpr88^+/+; K–N: n = 10, Gpr88^A2A-Cre; n = 9, Gpr88^flx/flx; O–R: n = 6, Gpr88 ^−/−; n = 6, Gpr88^+/+. Solid asterisks: *p < 0.05, **p < 0.01, ***p < 0.001 (Student’s t test).