[Cholinergic modulation of synaptic transmission in the spinal cord of the frog].
Superfusion of the isolated frog spinal cord by the Ringer solution containing arecoline (10 mumol/l) evoked depolarization and increase of the input resistance and PSP amplitude of motoneurons. Depolarizing electrotonic potentials and reflex discharges in the ventral roots also increased, but duration of dorsal root potentials decreased. The observed arecoline facilitation of synaptic transmission in the spinal cord has postsynaptic nature evoked by motoneuron M2-cholinoreceptor activation and bound to an increase of the cyclic nucleotide metabolism. Arecoline inhibited the synaptic transmission in the spinal cord under conditions when its postsynaptic action was eliminated. This effect was due to presynaptic M1-cholinoreceptor activation without changing the cyclic nucleotide metabolism.
D000818:Animals; D000870:Anterior Horn Cells / Q000502:physiology; D001115:Arecoline / Q000494:pharmacology*; D002799:Cholinergic Fibers / Q000502:physiology; D000242:Cyclic AMP / Q000502:physiology; D009475:Neurons, Afferent / Q000502:physiology; D011895:Rana ridibunda; D011976:Receptors, Muscarinic / Q000502:physiology*; D013116:Spinal Cord / Q000187:drug effects / Q000502:physiology*; D013569:Synapses / Q000502:physiology; D009435:Synaptic Transmission / Q000187:drug effects
D011976:Receptors, Muscarinic; D001115:Arecoline; D000242:Cyclic AMP
Kholinergicheskaia moduliatsiia sinapticheskoĭ peredachi v spinnom mozge liagushek.