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V L Cherepnov

Publications and source records attributed to V L Cherepnov.

17 recordsLinked to original sources
PubMed1985

[Effect of potassium and calcium channel blockers on changes in the transepithelial potential and spike responses of electroreceptors of the ampullae of Lorenzini in the skate].

Action of TEA, 4-AP, Co2+, Cd2+, Cs+, EDTA and verapamile on sensory epithelium of Lorenzinian ampullae was studied in the Black Sea skate Raja clavata. Application of TEA to the basal face of epithelium in current-clamped ampulla caused oscillations of transepithelial potential and oscillatory spike discharges in response to excitatory stimulation. The oscillations were suppressed by Co2+, Cd2+ and EDTA. Application of Cs+ was followed by partial or complete suppression of spike response adaptation. TEA injection into the ampulla produced an increase in the spike frequency reaction and speeding of adaptation. Co2+, Cd2+ and verapamile inside the ampulla caused almost no changes. The contribution of various ionic channels to the function of the electroreceptor cell is discussed.

4-Aminopyridine↗
PubMed1984

[Topography of the ampulla of Lorenzini system of Raja clavata and its role in electroorientation].

A detailed scheme is presented of the peripheral region of electroreceptive system of Raja clavata. These morphological data are used to calculate the overall energetic directional diagram (DD), i. e. response of the ampullary apparatus to the direction of uniform electric field strength vector. The calculations show that the overall DD of two major ampullar groups has a circular appearance. The experimentally obtained thresholds to electric stimulations determined from recordings of the vegetative reaction (respiratory reflex) are also circular. The data obtained allow suggesting that Raja clavata possesses a highly sensitive guard system capable of detecting any direction of electric field strength vector in a horizontal plane.

Animals↗
PubMed1984

[Reactions of the ampullae of Lorenzini of the skate to electric stimulation after polarization of the receptor epithelium].

Responses of electrically insulated Lorentzinian ampullae to d. c. pulses were studied on skates Raja clavata in the course of polarization of receptor epithelium. With negative polarization of -4 divided by -6 mV reversed changes in spike frequency (acceleration to anodal and inhibition to cathodal pulses) appeared practically without loss of sensitivity, the course of adaptation being unchanged. The data are in accordance with the model described previously suggesting stationary N-shaped voltage-current relation of receptor cell apical membrane.

Animals↗
PubMed1983

[Water-soluble proteins of Pacinian corpuscles].

The composition of water soluble proteins has been investigated in different parts of Pacinian corpuscles. The Pacinian corpuscles fluid proteins have been compared with the receptor homogenate proteins and blood serum of a cat. It is supposed that proteins of the Pacinian corpuscle fluid are produced from the blood system on the whole. The composition of the Pacinian corpuscle fluid as well as a great variety of glycoproteins in it allows to suppose that the Pacinian corpuscles fluid perform a transport function.

Albumins↗
PubMed1981

[Characteristics of soluble proteins of Pacinian corpuscles].

The paper describes some characteristics of water- and salt-soluble proteins from tissue mechanoreceptors (Pacini's corpuscles). The proteins were divided into fractions with different molecular weights with a purpose of determining fraction wise the content of nucleotides and protein-carbohydrate complexes. Possibilities of performing metabolic functions by soluble proteins and of creating a specific tissue mechanoreceptor microenvironment are discussed.

Glycoproteins↗
PubMed1976

[Mg, Ca-activated ATP-ase of Pacinian corpuscles].

Adenosine triphosphatase (ATPase) activated by Mg2+ or Ca2+ ions was detected in single mechanoreceptors (Pacini's corpuscles) of cat; addition of Ca2+ (10(-5)M) to Mg-ATP-ase increased the activity by the factor of 1.6. The activity optimum of Mg- or Co-ATPase was in the alkaline pH zone. A high substrate specificity of Mg, Ca-ATPase was shown. Parachlorinemercury-benzoate (5muM) considerably reduced the activity of Mg, Ca-ATPase, whereas oubain (10(-5)M) failed to affect it significantly. It is supposed that Mg, Ca-ATPase of Pacini's corpuscles was close to actomyosine -like proteins.

Adenosine Triphosphatases↗
PubMedDate not supplied

[Magnesium-activated adenosine triphosphate of the ampullae of Lorenzini of the skate Dasyatis pastinaca].

Studies have been made on Mg2+-activated ATPase of electroreceptor structures of the lateral line organin the ray D. pastinaca. It was shown that the enzyme is activated by magnesium ions (2.5 mM), maximum activation being observed at pH 8.0-8.5. The enzyme exhibits substrate specificity to adenyl nucleotides. Walls of ampullar canals also contain Mg2+-ATPase, however the level of the enzymatic activity in these walls is significantly lower.

Adenosine Triphosphatases↗
PubMedDate not supplied

[Characteristics of lactate dehydrogenase isoenzyme distribution in Pacinian corpuscles].

The paper deals with the isoenzymic LDG composition in different sections of Pacinian corpuscles. It is found that intracapsular liquid has the aerobic LDG spectrum. The stromal part of the receptor including lamellar capsule structures, inner cone and nerve endings has the anaerobic LDG spectrum. A conclusion is drawn that LDG aerobic LDG spectrum in the intracapsular liquid of Pacinian corpuscles confirms that the liquid is well saturated with oxygen.

Animals↗