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Biomedical subjects

V F Mashanskiĭ

Publications and source records attributed to V F Mashanskiĭ.

At least 37 records · Page 2Linked to original sources
PubMed1977

[Triggering and regulatory mechanisms of ciliary motion in the ctenophore Bolinopsis. III. Electric excitability and inherent contractility of ciliated cells].

Rhythmical electrostimulation is able to produce in a tissue strip of Bolinopsis series of beats of combs-plates. However, the beat frequency, within one series, is only poorly controlled by electrical stimuli. Isolated comb-plate cells with a cilium cut off maintain rhythmical contractions stimulated both mechanically and electrically. A lot of microtubules has been found in the apical region of these cells. It is supposed that it is these microtubules, probably together with the associated root filaments, that are responsible for cell motility. Mutual mechanical stimulation of ciliary cells in these motions is, presumably, a signal providing intratissue propagation of metachronal wave.

Animals↗
PubMed1976

[Strength of synaptic stimulation and morpho-functional reorganization of the neuron].

In the Retzius cell of the leech, synaptic threshold and three-fold threshold stimulation 1/sec was followed by readjustment of the cell spike activity according to the stimulation rhythm. After cessation of the stimulation the initial bioelectrical activity restores. The membrane potential remains unaltered during the three-fold threshold stimulation. Electron-microscopically, the Retzius cells develop different ultrastructural changes. In case of the threshold stimulationthe changes indicate an intensification of the synthetic processes and, on the contrary, the three-fold threshold stimulation is followed by a decrease in the proteinmetabolism. In the first case, the amount of granular endoplasmatic reticulum increases and in the second case -- decreases. The same is true for the total amount of ribosomes. During synaptic stimulation, the Retzius cell mitochondria remain unlatered while during the three-fold threshold stimulation the mitochondria swell, their matrix clears up, and their krysts become reduced.

Animals↗
PubMed1976

[Correlation of mitochondrial adenosine triphosphatase activity with their size following exposure of cells to higher temperatures].

Cells of the Unio tumidus gill ciliated epithelium were exposed to a supraoptimal temperature of 40 degrees C for the period from 30 seconds till a complete cessation of ciliar beating. ATPase activity of mitochondria of these cells being checked against their size during the corresponding period. The mitochondria were found to change their size in a phasic manner, swelling at the beginning of the temperature exposure, then shrinking and then swelling again. The ATPase activity increased during the first swelling and during shrinking to the control level. The data obtained indicate that similar ultrastructure and size of mitochondria may correspond to different levels of their functional activity.

Adenosine Triphosphatases↗
PubMed1976

[Conditions of spontaneous gelatinization of sarcoplasmic proteins].

Ca2+ ions at low concentration (10(-4)-10(-5) M) when added to ultracentrifugates of sarcoplasmic proteins with minimal content of sarcoplasmic reticulum fragments completely prevent protein gelatinization or gels, formed in these conditions, quickly dilute. Ca2+ ions at the concentration of 10(-3) M prevented in these conditions gelatinization in all the cases studied. Strong gels of sarcoplasmic proteins are formed afterwards in weak acid (pH 6.1-6.75), neutral (pH 7.0) and weak alkaline (pH 7.25-7.45 and higher) media. It is suggested that gelatinization of sarcoplasmic proteins is closely related with the development of plastic tonus, obturatory muscle function and viscous after-effect.

Animals↗