The tripartite synapse
The study of the astrocyte was hampered during the 1900s by the lack of experimental techniques to permit experimental stimulation and recording of the function of the astrocyte. Even in the early 1900s it was appreciated that electrical signals were the mechanism of conduction of neuronal signals (Adrian, 1912). Since astrocytes exhibit a large negative resting potential (Butt and Kalsi, 2006) their functional activity was mute to the electrophysiological techniques used to study nervous system function.
Despite the poor experimental tractability of astrocytes, several pioneering studies did, however, provide important insights into the functional roles for these glia in brain function. Microscopy, immunocytochemistry, and biochemistry were used to identify glycogen storage granules (Magistretti, 2006; Tsacopoulos and Magistretti, 1996), and the presence of glutamate transporters (Anderson and Swanson, 2000) in astrocytic membranes. These observations provided a basis for the...
KeywordsSynaptic Transmission P2Y1 Receptor Excitatory Synaptic Transmission Schaffer Collateral Astrocytic Process