Ventral dentate gyrus is activated under GALR2 and the Y1R
agonists intranasal infusion
The assessment of the successful delivery of M1145 and the Y1R agonists
to the brain via the i.n. route was confirmed by c-fos induction. The
i.n. administration of the Y1R agonist induced a significant increase in
the number of c-fos-IR profiles in the granular region of the ventral
dentate gyrus (one-way ANOVA, F4, 15 = 12.04, p < 0.001,
Newman-Keuls post-hoc test: p<0.05) (Figure 1 a,b) compared
with the control group. Conversely, the administration of the GalR2
agonist M1145 alone lacked effects on the numbers of c-fos positive
cells (Figure 1 b) compared with the control group (Figure 1 b, c).
Furthermore, M114545 and Y1R agonist coinjection significantly increased
the number of c-Fos-IR profiles in the granular region of the ventral
dentate gyrus compared with the M1145 and the control groups
(Newman-Keuls post-hoc test: p<0.001) and with the Y1R agonist
alone group (Newman-Keuls post-hoc test: p<0.05) (Figure 1 b,
d). The cotreatment with the GALR2 antagonist M871 specifically blocked
this M1145 and Y1R agonists coadministration effects in the ventral
dentate gyrus (Newman-Keuls post-hoc test: p<0.05) (Figure 1
b), indicating the participation of GALR2 in the Y1R-M1145 agonists
interaction to stimulate c-fos induction.