Depression of muscle spindle activity--a new type of pharmacological action?
The effect of 2,4-di(diethylamino)-6-(2-phenylacetylhydrazino)-1,3,5-triazine (Ciba 28882-Ba) injected intravenously on the activity of de-efferented muscle spindles of the tibialis anterior and extensor digitorum longus muscles of anaesthetized cats, and on gamma-motoneurones of decerebrate cats, was investigated. The drug depressed both the static activity of muscle spindles and the spontaneous activity of gamma-motoneurones. In contrast, the response of muscle spindles to rapid stretch was not affected. The effect of 28882-Ba on the activity of the muscle spindles resembled that of progressive unloading or shortening of the muscle. 28882-Ba antagonized excitation of the muscle spindle by suxamethonium. The effect of 28882-Ba on the response of the gamma-motoneurones to various driving stimuli was not predictable.
D000818:Animals; D002415:Cats; D003655:Decerebrate State; D009047:Motor Neurons, Gamma; D009125:Muscle Relaxants, Central; D009470:Muscle Spindles; D018482:Muscle, Skeletal; D009132:Muscles; D009411:Nerve Endings; D013390:Succinylcholine; D014227:Triazines
D009125:Muscle Relaxants, Central; D014227:Triazines; D013390:Succinylcholine
DECEREBRATE STATE; MUSCLE RELAXANTS; NERVE ENDINGS; SUCCINYLCHOLINE; TRIAZINES