Extracellular adenosine concentrations during in vitro ischaemia in rat hippocampal slices

摘要

1. The application of an ischaemic insult in hippocampal slices results in the depression of synaptic transmission, mainly attributed to the activation of A_1 adenosine receptors by adenosine released in the extracellular space. 2. To estimate the concentration of endogenous adenosine acting at the receptor level during an ischaemic episode, we recorded field e. p. s. ps (fe. P. s. ps) from hippocampal slices, and evaluatedthe ability of the selective A_1 receptor antagonist, 8-cyclopentyl-1, 3-dipropylxanthine (DPCPX), to reverse the fe. P. s. p. depression induced by in vitro ischaemia. A relationship between the IC_50 of an antagonist and the endogenous concentration of a neurotransmitter has been used for pharmacological analysis.