Modulation by C2 @entity2367 of the nicotinic transmission within the @entity4494 in the XXXX .

@entity20283 @entity6706 @entity95 @entity4494 @entity13740 @entity2367 @entity842 @entity43460
We have investigated the modulation by @entity2367 of the nicotinic activation of the prevertebral sympathetic neurons. Our study was performed in vitro in @entity95 isolated @entity4494 , using intracellular recording techniques. We have used @entity20283 , a permeant analog of @entity2367 . The effects of @entity20283 were first assessed when nicotinic activation was elicited without modulatory mechanisms (fast excitatory postsynaptic potentials triggered by stimulation of the thoracic splanchnic nerves with a single pulse). In all the neurons tested, C(2) @entity2367 triggered an increase in the amplitude of the fast excitatory postsynaptic potentials demonstrating a direct facilitatory effect on the nicotinic activation. We then investigated the effects of @entity20283 on modulatory mechanisms of this activation. These mechanisms occur when a train of pulses of supramaximum intensity is applied on the splanchnic nerves. During the train, a gradual depression of fast nicotinic activation occurred: the pulses failed to systematically elicit action potentials. We have previously demonstrated that this regulatory phenomenon is partly modulated by @entity842 which exerts a dual effect: facilitation or inhibition of the nicotinic activation. In all the neurons tested, @entity20283 decreased the number of action potentials fired during a train of pulses, demonstrating an indirect inhibitory effect on the nicotinic activation. The use of @entity6706 ( @entity842 scavenger) suppressed the inhibitory effect of @entity20283 , demonstrating that this effect is mediated through the @entity842 pathway. @entity43460 , an inactive analog of @entity2367 , was without effect on the nicotinic activation of the ganglionic neurons. These results demonstrate that @entity2367 exerts a complex modulation of the nicotinic activation of the prevertebral neurons: direct facilitation and indirect inhibition involving the @entity842 pathway. In fact, @entity20283 plays a key gating role in the dual effect of the @entity842 pathway by activating the inhibitory effect. The existence of this gating mechanism involving @entity2367 and @entity842 opens new perspectives in terms of our understanding of the modulation of synaptic transmission within the prevertebral ganglia. Our study demonstrates that @entity13740 are involved in complex modulations of the synaptic activation within the prevertebral ganglia, and thus contribute to their integrative properties.
