The depression of spinal inhibition by morphine
Tóm tắt
Electrophoretically administered morphine and codeine, but not meperidine, blocked the inhibitory effect of glycine on spinal neurones, without reducing the effectiveness of GABA. This action of morphine was similar to, but much weaker than, that of strychnine. When administered intravenously in divided doses to circumvent marked circulatory disturbances, morphine reduced the direct and recurrent inhibition of spinal motoneurones in a parallel fashion. Again morphine was a very weak strychnine-like substance, doses in excess of 50 mg/kg being required to block these disynaptic spinal inhibitions. The results are not incompatible with the function of a glycine-like amino acid as the inhibitory transmitter for both the direct and recurrent spinal inhibitory pathway.
Tài liệu tham khảo
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