Incorporation of fluorescently-labeled lipids into living brain slices

摘要

In order to identify neuronal networks, it is generally required to fix tissue followed by some specific staining procedure. A new procedure is described in this manuscript that labels brain slices that are routinely used for electrophysiological analyses. Fluorescently-labeled lipids can be incorporated into brain slices via passive exchange from exogenously applied vesicles. The labeled lipid is distributed throughout distinct cellular structures of the hippocampus and cerebellum. High resolution images of cells can be obtained and as the labeling process does not affect the electrical properties of the labeled cells, further electrophysiological analyses can be made of identifiable cells. The distribution of the lipid depends on the labeled phospholipid species. One of the lipids analyzed has been previously used for in vitro phospholipase analyses. Addition of phospholipase activating agents resulted in identification with high spatial and temporal resolution of activation of this enzyme in specific cell types. The cells affected correlated with previously identified regions of relevant pharmacological activity. This procedure shows considerable promise for monitoring biochemical changes due to physiological, toxicological or pathological changes in intact neuronal networks.