An American text-book of physiology . paralysis is something which pre-vents the nerve-impulse from passing from the nerve to the muscle. Micro-scopic examination shows that the nerve-fibre does not communicate directlywith the muscle-fibre, but ends inside the sarcolemma in an organ which iscalled the motor end-plate. It appears that the nerve acts on the musclethrough this organ, and its failure to act on the side which was exposed to thecurare was because the end-plate had been paralyzed by the drug. By theuse of curare, therefore, we are enabled to prevent the nerve-impulse fromreaching th
An American text-book of physiology . paralysis is something which pre-vents the nerve-impulse from passing from the nerve to the muscle. Micro-scopic examination shows that the nerve-fibre does not communicate directlywith the muscle-fibre, but ends inside the sarcolemma in an organ which iscalled the motor end-plate. It appears that the nerve acts on the musclethrough this organ, and its failure to act on the side which was exposed to thecurare was because the end-plate had been paralyzed by the drug. By theuse of curare, therefore, we are enabled to prevent the nerve-impulse fromreaching the muscles, and, when we have done this, we find that the muscleis still able to respond to direct excitation wnth all forms of irritants, viz. ^ Ch. Bernard : Analyse physiologique des Propri^t^s des Systemes mnsculaires et nerveuxau moyen-du Curare, Comptes-rendus, 1856, p. 825. KoUiker: Physiologische Untersuch-ungen iiber den Wirkungen einiger Gifte, Arckiv fur pathologische Anatomie, 1856. 42 AN AMERICAN TEXT-BOOK OF electrical, mechanical, thermal, and chemical. Evidently the muscle-proto-plasm is irritable and is caj)able of developing a contraction independently ofthe nerves. Other Proofs that the Muscle-protoplasm can be Directly Irritated.—Muscles with long [)arallel fibres, such as the sartorius of the fiog, contain nonerves at tiieir extremities, the nerve-fibres joining thenuiscle-fibres at some little distance from their tip of such a muscle, where no nerve-fibres canbe discovered by the most careful microscopical exam-ination, is found to be irritable. The fact that in someof the lower animals there are simple forms of contrac-tile tissue in which nerves cannot be discovered, andwhich are irritable, is interesting as corroborative evi-dence, although it is not a proof, of the independentirritability of a highly diffi?rentiated tissue such asstriated muscle. Another similar piece of evidence isto be found in the fact that the heart of the em
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