Differentiation of forebrain and hippocampal @entity935 1-class receptors, D1R and XXXX , in spatial learning and memory.

@entity53611 @entity935 @entity19 @entity4778 @entity51 @entity2414
Activation of prefrontal cortical (PFC), striatal, and hippocampal @entity935 1-class receptors (D1R and @entity53611 ) is necessary for normal spatial information processing. Yet the precise role of the D1R versus the @entity53611 in the aforementioned structures, and their specific contribution to the water-maze spatial learning task remains unknown. D1R- and D5R-specific in situ hybridization probes showed that forebrain restricted D1R and D5R KO @entity19 (F-D1R/ @entity53611 KO) displayed D1R mRNA deletion in the medial (m)PFC, dorsal and ventral striatum, and the dentate gyrus (DG) of the hippocampus. D5R mRNA deletion was limited to the mPFC, the @entity4778 and DG hippocampal subregions. F-D1R/D5R KO @entity19 were given water-maze training and displayed subtle spatial latency differences between genotypes and spatial @entity2414 during both regular and reversal training. To differentiate forebrain D1R from D5R activation, forebrain restricted D1R KO (F-D1R KO) and D5R KO (F-D5R KO) @entity19 were trained on the water-maze task. F-D1R KO animals exhibited escape latency deficits throughout regular and reversal training as well as spatial @entity2414 during reversal training. F-D1R KO @entity19 also showed perseverative behavior during the reversal spatial memory probe test. In contrast, F-D5R KO animals did not present observable deficits on the water-maze task. Because F-D1R KO @entity19 showed water-maze deficits we tested the necessity of hippocampal D1R activation for spatial learning and memory. We trained DG restricted D1R KO (DG-D1R KO) @entity19 on the water-maze task. DG-D1R KO @entity19 did not present detectable spatial @entity2414 , but did show @entity51 during specific days of training. Our data provides evidence that forebrain D5R activation plays a unique role in spatial learning and memory in conjunction with D1R activation. Moreover, these data suggest that mPFC and striatal, but not DG D1R activation are essential for spatial learning and memory.
