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J V Luco

Publications and source records attributed to J V Luco.

5 recordsLinked to original sources
PubMed1979

The Rosenblueth phenomenon.

Rosenblueth and Luco demonstrated in 1939 that, during prolonged stimulation of a motor nerve, neuromuscular fatigue is followed by a rise of tension that has been called the Rosenblueth Phenomenon. The purpose of this work was to investigate the Rosenblueth Phenomenon in a cat neuromuscular preparation in which the nerves were severed at different levels and stimulated at 60 Hz for several hours. It was demonstrated that in the longer nerve preparation the Rosenblueth Phenomenon starts earlier and its maximal tension is higher. Acetylcholine sensitivity was studied in the superior cervical ganglion preparation and no change was observed when tested before stimulation, during fatigue, and during the Rosenblueth Phenomenon. It is concluded that the onset and amplitude of the Rosenblueth Phenomenon depend on the length of the peripheral nerve stump: the longer the stump, the earlier and higher the response. It is suggested that the Rosenblueth Phenomenon is produced by an increase in the transmitter release which would be due to axonal progression of molecules along the nerve.

Acetylcholine↗
PubMed1975

Modification of synaptic efficiency, experiments in blatta orientalis.

The efficiency of synapt ic transmission in a nervous pathway--metathoracic ganglia from the cockroach--can be increased by various experimental situations, i.e., removal, immobilization or denervation of the forelegs of insects in ventral position. Leg immobilization with the insect in supine position by itself determines a minor increase which is not enhanced by removal or denervation of the forelegs. Under these conditions, the insects are able to hold their antennae with a midleg immediately after any of the leg treatments. On the other hand, if the insects are allowed to be in ventral position they can hold their antennae with a midleg only when they reach the ability to stand on the remaining three legs. During the time period needed to acquire this ability, the insects make repeated and spontaneous motor effects. The increase in synaptic efficiency observed and the achievement of the insect's ability to stand on three legs occur at about the same time. These observations suggest that the self-training determines the synaptic modifications which in turn could be related to the "learnt" behavioral reaction.

Animals↗