FIGURE 3.

Spatial memory assessment after M1145 and the NPY1R agonist alone and combined in the object-in-place memory task. (A) Schematic representation of the trials completed in the object-in-place task. The animals performed the task in three phases, divided 24 h from each other, where they explored freely for 10 min in the habituation phase without objects, 3 min in the training phase with four different objects, and finally, 3 min in the test phase with two of the objects with the exchanged position. To achieve memory consolidation, the pharmacological treatments were administered intracerebroventricularly (icv) to the different groups of animals 3 weeks before the testing phase. (B) Performance on the object-in-place task showing the ability of rats to discriminate the exchanged objects 3 weeks after the icv administration of M1145 in combination with the NPY1R agonist. An improvement in the object-in-place performance was observed after M1145 and NPY1R agonist co-administration, and this effect is counteracted by the GAL 2 receptor (GALR2) antagonist M871. Data are presented as the mean ± SEM of the discrimination ratio on the test phase. n = 6 animals in each group. *p < 0.05 vs. the rest of the groups according to one-way ANOVA followed by Newman–Keuls post-hoc test. aCSF, Control (artificial cerebrospinal fluid); M1145, Galanin receptor 2 agonist (3 nmol); NPY1R agonist, NPY1R receptor agonist [Leu31, Pro34]NPY (3 nmol); M1145 + NPY1R, co-administration of M1145 and NPY1R agonist; M1145 + NPY1R + M871, co-administration of M1145, NPY1R, and GALR2 antagonist M871 (3 nmol).