Neuropsychopharmacological study of 2,4-dihydro[1,2,4]triazolo[3,4-c][1,4]benzothiazine-1-one (IDPH-791).
The neuropsychopharmacological profile of a new centrally acting skeletal muscle relaxant, 2,4-dihydro[1,2,4]triazolo[3,4-c][1,4]benzothiazine-1-one (IDPH-791), an analogue of triazolobenzothiazine, has been described and compared to mephenesin, a well known centrally-acting muscle relaxant. IDPH-791 was found to be safer and of longer duration of action than mephenesin in all the tests conducted in this study. Both IDPH-791 and mephenesin caused ataxia, decrease in spontaneous activity and inhibition of pinnal reflex. IDPH-791 was 1.5 to 2.0 times more potent in exhibiting motor inco-ordination and anticonvulsant activity than mephenesin in mice and rats. IDPH-791 was twice as active in inhibiting various spinal polysynaptic reflexes, crossed extensor, flexor, and linguomandibular reflexes; however, both did not affect the typical monosynaptic reflex, patellar reflex. IDPH-791 and mephenesin did not have sedative activity. Although mephenesin exhibited haemolytic activity, IDPH-791 was devoid of this activity. It is concluded that IDPH-791 is a safe and effective centrally-acting muscle relaxant having a longer duration of action than mephenesin. IDPH-791 is also devoid of sedative and haemolytic activity.
Junnarkar
A Y
AY
Department of Pharmacology, IDPL Research Centre, Balanagar Township, Hyderabad, India.
Singh
P P
PP
Patnaik
G K
GK
Shrotri
D S
DS
D000284:Administration, Oral; D000818:Animals; D001921:Brain / Q000187:drug effects*; D006990:Hypnosis; D007274:Injections, Intraperitoneal; D007928:Lethal Dose 50; D008615:Mephenesin / Q000008:administration & dosage / Q000494:pharmacology / Q000633:toxicity; D051379:Mice; D009043:Motor Activity / Q000187:drug effects*; D009125:Muscle Relaxants, Central / Q000008:administration & dosage / Q000494:pharmacology* / Q000633:toxicity; D009126:Muscle Relaxation / Q000187:drug effects*; D010243:Paralysis / Q000139:chemically induced; D011817:Rabbits; D051381:Rats; D017208:Rats, Wistar; D012640:Seizures / Q000517:prevention & control; D013843:Thiazines / Q000494:pharmacology*; D014230:Triazoles / Q000494:pharmacology*
D009125:Muscle Relaxants, Central; D013843:Thiazines; D014230:Triazoles; D008615:Mephenesin; C070154:IDPH-791