Selective antinociceptive effects of tizanidine (DS 103-282), a centrally acting muscle relaxant, on dorsal horn neurones in the feline spinal cord

Effect of the centrally acting muscle relaxant tizanidine on spinal reflexes: involvement of descending noradrenergic systems.

Experiments were performed on intact and spinalized rats anesthetized with urethane and alpha-chloralose. In intact rats, administration of tizanidine (0.1 mg/kg, i.v.) decreased the mono- (MSR) and polysynaptic reflex potentials (PSR). Blood pressure was initially elevated and then lowered by tizanidine. Although pretreatments with hexamethonium and phentolamine prevented the tizanidine-induce...

Dorsal Horn of the Spinal Cord

Enhanced inhibitory synaptic transmission in the spinal dorsal horn mediates antinociceptive effects of TC-2559

BACKGROUND TC-2559 is a selective α4β2 subtype of nicotinic acetylcholine receptor (nAChR) partial agonist and α4β2 nAChR activation has been related to antinociception. The aim of this study is to investigate the analgesic effect of TC-2559 and its underlying spinal mechanisms. RESULTS 1) In vivo bioavailability study: TC-2559 (3 mg/kg) had high absorption rate in rats with maximal total bra...

Basic Aspects of the Pharmacodynamics of Tolperisone, A Widely Applicable Centrally Acting Muscle Relaxant

Tolperisone (2-methyl-1-(4-methylphenyl)-3-piperidin-1-ylpropan-1-one hydro-chloride) was introduced in the clinical practice more than forty years ago and is still evaluated as a widely applicable compound in pathologically elevated skeletal muscle tone (spasticity) and related pains of different origin. In the present review, basic pharmacodynamic effects measured on whole animals, analyses o...

Selective suppression of inhibitory synaptic transmission by nocistatin in the rat spinal cord dorsal horn.

Nociceptin/orphanin FQ (N/OFQ) and nocistatin (NST) are two recently identified neuropeptides with opposing effects on several CNS functions, including spinal nociception. The cellular mechanisms that underlie this antagonism are not known. Here, we have investigated the effects of both peptides on synaptic transmission mediated by the three fast neurotransmitters l-glutamate, glycine, and GABA...