| Spatial orientation depends on multiple intact neural systems to guide an animals' navigation throughout an environment. Previous research has demonstrated a relationship between cholinergic function in the medial septum and spatial orientation. In addition to cholinergic neurons, the GABAergic system projects from the medial septum into the hippocampus producing a strong dis-inhibitory effect, suggesting that GABA could contribute to spatial orientation. Initial studies using non-selective lesion techniques have supported the involvement of this system in spatial orientation; however, the development of an immunotoxin (i.e., GAT1-Saporin) that selectively targets GABAergic neurons, allows for a novel technique in which to study this relationship. The current study examined the effect of infusing GAT1-Saporin (n=6) or saline ( n=6) into the medial septum (MS) on performance in the food-hoarding paradigm and the standard water maze. Disruption in GAT1 rats' performance was observed when environmental cues were eliminated, i.e., testing under dark conditions. The current study adds to the expanding literature that supports a role for components of the septohippocampal system in self-movement cue processing during spatial navigation. |
