Differential effects of mercurial and methylmercurial ions on the phrenic nerve and diaphragm of the XXXX .

@entity10694 @entity308 @entity19 @entity1022 @entity2041 @entity653 @entity855 @entity1159 @entity141 @entity2899 @entity5165
Both @entity10694 and @entity5165 + exert a @entity308 action on the twitch amplitude elicited by nerve stimulations more rapidly than that by muscle stimulation. @entity5165 + was relatively more potent than @entity10694 in the nerve @entity308 action but was weaker on the muscle. @entity10694 induced a rapid phase and a slow phase of @entity1159 in the diaphragm, while @entity5165 + induced only a slow one. The biphasic @entity1159 induced by @entity10694 could be inhibited by repetitive washout of the diaphragm with low @entity141 (10(-3) mM) Krebs and also by treatment with @entity653 to close T-tubule, while the slow @entity1159 induced by @entity5165 + was little affected by @entity653 treatment. None of denervation, @entity2899 and @entity1022 inhibited the @entity1159 induced by @entity10694 and @entity5165 +, indicating that the @entity1159 was induced by a direct action on the muscle. @entity10694 , but not @entity5165 +, rapidly caused a decrease of the membrane potential, decreased the amplitude and prolonged the duration of the muscle action potential. @entity10694 also initially decreased and then increased 45 @entity141 uptake of the diaphragm, but @entity5165 + had no effect, except a prolonged incubation at a high concentration. The action of @entity10694 could be antagonized by @entity2041 , and @entity5165 + was more susceptible than @entity10694 to the antagonistic action of @entity2041 . Both @entity10694 and @entity5165 + did not change the @entity855 content of the diaphragm. All of these findings indicate that the monovalent organic @entity5165 +, with a higher lipophilicity, possesses a higher affinity to the nerve while the divalent cationic @entity10694 exerted more effects than @entity5165 + on the sarcolemma of the @entity19 diaphragm.
