Lesion of the bulbospinal noradrenergic pathways blocks desipramine-induced inhibition of the C-fiber evoked nociceptive reflex in rats
Desipramine-induced inhibition of spinal cord nociceptive transmission was studied in rats with or without lesion of the bulbospinal noradrenergic system by recording the C-fiber evoked nociceptive reflex from a hind limb. Bulbospinal noradrenergic projections were lesioned by injecting intrathecally 20 ?g of 6-hydroxydopamine 2 weeks before the electrophysiological experiments. Results show that desipramine (5, 10 and 20 mg/kg intraperitoneally) produced dose-dependent inhibition of the C reflex response duration in rats having intact noradrenergic bulbospinal systems. The inhibitory effect of desipramine was reduced or even abolished in rats pre-treated with 6-hydroxydopamine. In addition, [3H]-noradrenaline uptake was significantly lower in spinal cord slices arising from 6-hydroxydopamine lesioned animals, as compared to that from intact rats. These observations support the notion that the antinociceptive activity of antidepressants with noradrenergic selectivity depends on a normal rate of endogenous noradrenaline released by bulbospinal neurons. © 2001 Elsevier Science Ireland Ltd.
|Título según WOS:||Lesion of the bulbospinal noradrenergic pathways blocks desipramine-induced inhibition of the C-fiber evoked nociceptive reflex in rats|
|Título según SCOPUS:||Lesion of the bulbospinal noradrenergic pathways blocks desipramine-induced inhibition of the C-fiber evoked nociceptive reflex in rats|
|Título de la Revista:||NEUROSCIENCE LETTERS|
|Editorial:||ELSEVIER SCI IRELAND LTD|
|Fecha de publicación:||2001|
|Página de inicio:||1|