Yu. I. Arshavskii

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Motion pictures were taken of the locomotion of two species of ophiurans living in the Sea of Japan:Ophiura sarsi vadicoa Djakonov andAmphipholis kochii Lutken.Ophiura sarsi was found to move with the aid of paddling movements of two pairs of arms: The fifth arm (passive) pointed backward. Ophiurans of this species do not use their ambulacral feet. Three(More)
During movement of the ophiuranAmphipholis kochii Lutken, any one of its arms can point forward and, consequently, any arm can perform different functions. The arm, when separated from the ophiuran together with the adjacent part of the nerve ring, is capable of complex motor acts, including locomotion. Division of the nerve ring in the ophiuran disturbs(More)
In the pedal ganglia ofClione limacina the growth of neurites is traced in motoneurons after transection of the wing nerve and in interneurons after transection of the pedal commissure. Neurons were stained intracellularly with Lucifer yellow. In the motoneurons the neurites growing from the transected end of the axon and from the neuron soma spread to all(More)
A two-stage defense response was induced in the freshwater snailPlanorbarius corneus by stimulating the head. It consisted of the shell being rapidly lowered over the head and foot followed by the snail gradually withdrawing into its shell. These movements are performed by contracting the columellar muscle. Motoneurons of the columellar muscle were(More)
It was established during experiments on pedal ganglia generating locomotor rhythm isolated fromClione limacina, a pteropod mollusk, that this rhythm was irregular in 30% of preparations; i.e., the locomotor generator worked in bursts which alternated with periods of regular activity. Locomotor bursts were produced by excitation in command neurons located(More)
Field potentials evoked in the graunular layer of the cerebellar paramedian lobule of unanesthetized cats in response to stimulation of the sensomotor cortex and limb nerves contained slow negative waves, appearing after a long latent period, which were generated by granule cells. In the case of nerve stimulation this component was recorded both inside and(More)
Tilting of the freshwater snailPlanorbarius corneus triggering dynamic statocyst receptor response resulted in defense reaction attended by rapid lowering of the shell over the head, foreshortening of the foot, and inhibited locomotion and buccal apparatus operation. Large numbers of neurons from different ganglia were found to take part in this reaction in(More)
We recorded the activity of two types of granular cells in the rostral folia of the paramedial lobe (the projection region of the front legs) of the cerebellar cortex in cats immobilized by administration of ditiline; these cells differed in their receptive fields, the characteristics of their reaction to single stimulation of somatic nerves, and the(More)
Neurons from the peripharyngeal nerve ring detached from the pteropodial molluskClione limacina were cultured in polylysine prepared in a 25% Leibovitz saltwater medium containing 2% embryonic calf serum. Neurite outgrowth was observed in a proportion of the neurons, reaching its peak rate during the first three days. Neurites grew up to 300 µm in length.(More)
The effect of the central analgesic fentanyl on evoked potentials and responses of single Purkinje cells in the cerebellar cortex to stimulation of the sensomotor cortex and of somatic nerves was investigated in unanesthetized cats. Injection of fentanyl in an analgesic dose (10–30 µg/kg, intravenously) had no appreciable effect on evoked potentials and led(More)