Nicotinic and muscarinic cholinergic receptors are recruited by acetylcholine-mediated neurotransmission within the locus coeruleus during the organisation of post-ictal antinociception.

Nicotinic and muscarinic cholinergic receptors are recruited by acetylcholine-mediated neurotransmission within the locus coeruleus during the organisation of post-ictal antinociception.
Brain Res Bull. 2016 Aug 22;
Authors: de Oliveira RC, de Oliveira R, Franceschi Biagioni A, Falconi-Sobrinho LL, Dos Anjos-Garcia TD, Cysne Coimbra N
Abstract
Post-ictal antinociception is characterised by an increase in the nociceptive threshold that accompanies tonic and tonic-clonic seizures (TCS). The locus coeruleus (LC) receives profuse cholinergic inputs from the pedunculopontine tegmental nucleus. Different concentrations (1μg, 3μg and 5μg/0.2μL) of the muscarinic cholinergic receptor atropine and the nicotinic cholinergic receptor antagonist mecamylamine were microinjected into the LC of Wistar rats to investigate the role of cholinergic mechanisms in the severity of TCS and the post-ictal antinociceptive response. Five minutes later, TCS were induced by systemic administration of pentylenetetrazole (PTZ) (at 64mg/kg). Seizures were recorded inside the open field apparatus for an average of 10min. Immediately after seizures, the nociceptive threshold was recorded for 130min using the tail-flick test. Pre-treatment of the LC with 1μg, 3μg and 5μg/0.2μL concentrations of both atropine and mecamylamine at did not cause a significant effect on seizure severity. However, the same treatments decreased the post-ictal antinociceptive phenome...

Source: Brain Research Bulletin - August 21, 2016 Category: Neurology Authors: de Oliveira RC, de Oliveira R, Franceschi Biagioni A, Falconi-Sobrinho LL, Dos Anjos-Garcia TD, Cysne Coimbra N Tags: Brain Res Bull Source Type: research