Selective lesion of GABA-ergic neurons in the medial septum by GAT1-saporin impairs spatial learning in a water-maze.

The aim of this study was to investigate the role of the medial septal (MS) GABAergic cells in hippocampal dependent spatial learning using the immunotoxin GAT1-SAP to produce selective lesions of GABAergic MS neurons. In current study rats were trained in a visible platform version of the Morris water maze in which either a place or cue strategy could be used to escape successfully. Immunohistochemical studies showed that intraseptal injection of GAT1-SAP extensively damaged GABAergic MS neurons and spared most cholinergic neurons.

Effects of immunotoxic and electrolytic lesions of medial septal area on spatial short-term memory in rats.

In the present study electrolytic and the immunotoxins (192 IgG saporin and GAT1-SAP) lesions of medial septal area (MS) were used to investigate the importance of cholinergic and GABAergic MS neurons in spatial working memory using spatial alternation task. In our experiments electrolytic lesions destroyed on average 69% of the intact MS. Examination of the AChE stained sections showed that after injections of 192 IgG saporin into the MS, animals exhibited significantly less AChE staining in MS as compared to sections obtained from control animals.