Sites of action of CS-722, a newly synthesized centrally acting muscle relaxant.
Sites of the muscle relaxant action of CS-722 were investigated in rats. Doses injected intra-4th ventricularly (i.c.v.) or intrathecally (i.t.) were determined according to measurements of CS-722 concentration in the brain stem and the spinal cord after systemic administration. When administered i.c.v. (50 and 100 micrograms) or i.t. (200 and 400 micrograms), CS-722 reduced the radio frequency decerebrate rigidity, although the effect after i.c.v. injection was transient. These results indicate that CS-722 exerts its muscle relaxant action by affecting both the supraspinal structure and the spinal cord. Spinal reflexes were not affected by CS-722 injected i.c.v. It seems that muscle relaxation is not always accompanied by impairment of the spinal reflex.
Tanabe
M
M
New Lead Research Laboratories, Sankyo Co., Ltd., Tokyo, Japan.
Ishizuka
H
H
Murayama
T
T
Kaneko
T
T
Tonohiro
T
T
Sakai
J
J
Nagano
M
M
Sasahara
K
K
Iwata
N
N
D000818:Animals; D001933:Brain Stem / Q000187:drug effects* / Q000378:metabolism; D003655:Decerebrate State; D007276:Injections, Intraventricular; D007278:Injections, Spinal; D007555:Isoxazoles / Q000378:metabolism / Q000494:pharmacology*; D008297:Male; D009025:Morpholines / Q000378:metabolism / Q000494:pharmacology*; D009125:Muscle Relaxants, Central / Q000008:administration & dosage / Q000378:metabolism / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D012018:Reflex / Q000187:drug effects*; D013116:Spinal Cord / Q000187:drug effects* / Q000378:metabolism / Q000502:physiology
D007555:Isoxazoles; D009025:Morpholines; D009125:Muscle Relaxants, Central; C077576:CS 722