| pubmed-article:11872246 | pubmed:abstractText | Actions of anandamide (10 microM) were examined on monosynaptic glutamatergic transmission from the periphery to substantia gelatinosa (SG) neurones in adult rat spinal cord slices using the whole-cell patch-clamp technique. In 64% of neurones examined, Adelta-fibre-evoked excitatory postsynaptic currents (EPSCs) were depressed (in amplitude; by 32 +/- 4%, n=21) by anandamide. On the contrary, an inhibitory action on C-fibre-evoked EPSCs was observed in only 31% of neurones tested; this magnitude (17 +/- 3%, n=4) was less than that of Adelta-fibre EPSCs (P<0.05). A cannabinoid-receptor agonist, WIN 55,212-2 (5 microM), exhibited similar actions on the EPSCs. In a neurone with minimal effects of anandamide on C-fibre EPSCs, capsaicin (1 microM) largely depressed the EPSCs (n=3); Adelta-fibre EPSCs were little affected by capsaicin. It is concluded that unlike capsaicin, anandamide inhibits more effectively Adelta-fibre than C-fibre-mediated excitatory transmission in the SG, possibly through the activation of the cannabinoid receptor. | lld:pubmed |
