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M Hisada

Publications and source records attributed to M Hisada.

65 records · Page 4Linked to original sources
PubMed1984

The effects of acetylcholine, carbamylcholine and gamma-aminobutyric acid on uropod motoneurons in the crayfish Procambarus clarkii and Cambaroides japonicus.

The effects of acetylcholine (ACh), carbamylcholine and gamma-aminobutyric acid (GABA) on the spike activity of uropod motoneurons were investigated electrophysiologically in the crayfish Procambarus clarkii Girard and Cambaroides japonicus de Haan. High concentrations of ACh were required to bring about an increase in the spike discharge of uropod motoneurons while carbamylcholine, which is not destroyed by cholinesterase, caused a marked increase in the motoneuron spike discharge even in low concentrations. Application of GABA in concentrations of 10(-5)-10(-2) M caused the decrease in the spike discharge of uropod motoneurons. Under the condition that the synaptic transmission onto uropod motoneurons was blocked by perfusing EGTA containing Ca2+-free saline with high-Mg2+, ACh increased the spike discharge of uropod motoneurons whereas GABA decreased it. The results suggested that ACh and GABA function as excitatory and inhibitory transmitters, respectively, in the crayfish central nervous system.

Acetylcholine↗
PubMed1983

Projection of statocyst sensory neurons associated with crescent hairs in the crayfish Procambarus clarkii girard.

The central projection of statocyst sensory neurons associated with the crescent hairs of the crayfish Procambarus clarkii was investigated. Cobalt fills of statocyst nerves revealed that they entered the brain as the two discrete fiber bundles and terminated in different portions of the brain. One terminates in the ipsilateral half of the brain and the other in the contralateral half. The later was further subdivided into two discrete components. The relationship between the location of statocyst receptors in the different regions of the crescent and their central projection pattern was investigated by the extracellular cobalt marking method. The results showed that the two fiber bundles, which projected to the ipsilateral and contralateral halves of the brain respectively, originated from different regions of the crescent. Ipsilaterally projecting neurons had their origin mainly in the posterior hairs of the sensory crescent whereas contralaterally projecting ones in the anterior hairs of the sensory crescent.

Animals↗
PubMed1981

Physiological and morphological characterization of anaxonic non-spiking interneurons in the crayfish motor control system.

Spike activation of the motoneurons innervating uropod muscles in crayfish is controlled by anaxonic interneurons located within the terminal (the 6th abdominal) ganglion. These neurons do not generate spikes either spontaneously at the resting potential level or in response to current injection of either polarity. Yet the change in the membrane potential of these non-spiking interneurons caused an increase or decrease in the discharge frequency of motoneuron spikes, depending upon the direction of the membrane potential change. These non-spiking interneurons within the terminal ganglion presumably integrate various descending command signals and select the adequate information to be gated to the motoneurons.

Animals↗
PubMed1978

Flow and potentials during perfusion of lacrimal gland with electrolyte solutions.

Resting membrane potentials, acetylcholine (ACh)-induced change in membrane potentials of lacrimal gland cells, and ACh-induced flow from the excretory duct of the lacrimal gland were recorded during close intra-arterial perfusion of various electrolyte solutions. Resting membrane potentials were unchanged during perfusion with Na+-free, Cl--free, K+-free, and K+-rich solutions. Regardless of the composition of the perfusion solution, ACh induced hyperpolarization of the majority of cells but it also induced depolarization or biphasic potential or no change in potential in a significant number of cells. When the gland was perfused with a Na+-free or a Cl--free solution, the magnitude of the ACh-induced hyperpolarization was not changed but ACh-induced flow was markedly decreased. We conclude that the process(es) responsible for the ACh-induced change in potential may differ from those responsible for the ACh-induced flow and caution should be used when drawing conclusions about mechanisms of secretion solely from analysis of electrophysiological data.

Acetylcholine↗