Biomedical subjects

K A Gol'fand

Publications and source records attributed to K A Gol'fand.

3 recordsLinked to original sources

PubMed1978

[Fluorescence anisotropy and myelin structure. III. Effect of temperature changes on the orientation of dye molecules in nerve fibers].

The temperature dependence of fluorescence polarization of stained nerve fibres has been studied. As has been previously demonstrated by the authors, the dependence of fluorescence polarization on the angle between the electrical vector of exciting light and the fibre axis (azimuth characteristics) is associated with the molecular orientation of dyes adsorbed on the membranes of the myelin sheath. This permits an indirect conclusion to be made about the structure and structural changes of an adsorbent. The experiments with changing temperature show that the molecular orientation of dyes decreases with decline of temperature from the room temperature to the freezing point of the Ringer solution. The structure of myelin membranes is suggested to be stabilized through hydrophobic interaction.

Acridines↗

PubMed1977

[Fluorescence anisotropy and the structure of myelin. I. The theory of the method].

Theoretical aspects of the experiment dealing with measurements of fluorescence polarization degrees in stained myelinated nerve fibres are considered. Fluorescence polarization (FP) largely depends on the excitation azimuth, i.e. on the angle between the electrical vector of the polarized exciting light and the nerve fibre axis (geometrically it is a figure with the cylinder symmetry). The dependence of FP on the excitation azimuth is shown to be related to the degree of molecular orientation of dyes adsorbed on anisotropic layers of myelin membranes. This permits to associate FP with the structural changes of myelin membranes.

Animals↗

PubMed1976

[Effect of various antimicrotubular drugs on the osmotic water flow through the wall of frog's urinary bladder].

The action of antimicrotubular drugs (colchicine, vinblastine and copper) on the osmotic water flow through the wall of the urinary bladder of Rana temporaria has been studied. The osmotic gradient was made by five- or tenfold dilution of the internal Ringer solution. The water flow was estimated gravimetrically. The water flow was induced by pituitrin (50 milliunits/ml), cyclic AMP (cAMP, 0.5-10(-3) M) and nystatine (3.5-10(-5) M). Pituitrin and cAMP and all the antimicrotubular drugs were added from the serosal surface of the bladder. Nystatine was introduced with the help of a fixed polyethylene tube. Preincubation with colchicine lasted 4 hours and that with vinblastine and copper (CuSO4), 1 hour. The drug concentrations varied between 10(-5)--10(-4) M. All the drugs studied showed a significant inhibitory effect toward pituitrin. The action of cAMP on the water flow was seen inhibited in the presence of colchicine and copper. The nystatine induced water flow was supressed by copper, colchicine being in this case inactive. A conclusion is drawn that the inhibition of cAMP formation does not cause a decreased pituitrine effect in the presence of antimicrotubular drugs. It has been assumed that the microtubules may be involved in the directed water flow within the cell.

Animals↗