title: The pharmacology of 5-chloro-4-(2-imidazolin-2-yl-amino)-2,1,3-benzothiadiazole (DS 103-282), a novel myotonolytic agent.
abstract: 5-Chloro-4-(2-imidazolin-2-yl-amino)-2,1,3-benzothiadiazole (DS 103-282) is a centrally acting agent with a novel chemical structure and a pharmacological profile different from that of myotonolytic drugs in current use such as diazepam, baclofen and dantrolene. It inhibits alpha- and gamma-rigidity in rats, reflex muscle tone in rabbits and the linguomandibular reflex in cats at low doses, but has little or no effect on gross spinal reflexes or electrically-induced segmental reflexes in cats. The mechanism underlying the muscle relaxation is unknown. Effects on convulsions induced by impaired GABA-transmission and by strychnine suggest a possible influence on glycine-mediated neurotransmission. In muscle-relaxing doses, DS 103-282 is without appreciable sedative, haemodynamic or neurochemical effects. Clinical investigations have confirmed the pharmacological predictions with regard to both the myotonolytic activity and the low propensity to produce side-effects.
mesh_terms: D000700:Analgesics; D000818:Animals; D000927:Anticonvulsants; D001522:Behavior, Animal / Q000187:drug effects; D001923:Brain Chemistry / Q000187:drug effects; D003000:Clonidine / Q000031:analogs & derivatives* / Q000494:pharmacology; D004569:Electroencephalography; D005116:Extrapyramidal Tracts / Q000187:drug effects; D005260:Female; D006439:Hemodynamics / Q000187:drug effects; D007668:Kidney / Q000187:drug effects; D008297:Male; D009046:Motor Neurons / Q000502:physiology; D009125:Muscle Relaxants, Central / Q000494:pharmacology*; D009129:Muscle Tonus / Q000187:drug effects; D051381:Rats; D012018:Reflex / Q000187:drug effects; D013569:Synapses / Q000187:drug effects
chemical_list: D000700:Analgesics; D000927:Anticonvulsants; D009125:Muscle Relaxants, Central; C023754:tizanidine; D003000:Clonidine