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Biomedical subjects

N G Grigor'ev

Publications and source records attributed to N G Grigor'ev.

12 recordsLinked to original sources
PubMed1986

[Changes in the acetylcholine responses of perfused neurons of Limnaea stagnalis during internal and external exposure of the cell].

The modifying effect of extra- and intracellular administration of serotonin on inward currents generated by the cell at extracellular application of acetylcholine was studied. The study was made on nonidentified isolated neurons of the fresh water mollusc Lymnaea stagnalis using the voltage-clamp and intracellular perfusion methods. In roughly a half of the studied cells serotonin being added intra- and extracellularly produced a decrease in the response to acetylcholine. In the other half of neurons serotonin being added intracellularly increased the acetylcholine response, but applied extracellularly showed the opposite effect: it decreased the magnitude of inward acetylcholine currents. The blocker of serotonin receptors, cyproheptadine, blocks the enhancing effect of serotonin on the intracellular addition of the mediator, but mimics the inhibitory effect of serotonin on acetylcholine response. The data obtained on the neurons of molluscs suggest the existence of intracellular receptors of serotonin one whose possible functions is the regulation of sensitivity of the cell surface cholinoreceptors.

Acetylcholine↗
PubMed1985

[Transduodenal papillosphincteroplasty using special instruments].

The work compares results of experimental investigations and clinical analysis of transduodenal papillosphincretoplasty by a routine technique and by the author's modification of the method without mobilization of the duodenum and pancreas head using special instruments such as a multiolive probe and a fixator of the major duodenal papilla and duodenum. The transduodenal papillosphincteroplasty fulfilled by the author's modification was shown to be less traumatic. It does not disturb the state of nerve plexuses of the duodenum wall, gives less amount of postoperative complications and better results.

Ampulla of Vater↗
PubMed1984

[Effect of cyclic nucleotides on the sensitivity of early sea urchin embryos to cytotoxic neuropharmacological preparations].

It has been shown that cytotoxic action of neuropharmacological drugs (transmitter antagonists) on early urchin embryos is reduced or abolished by cyclic nucleotides and sodium fluoride. Such a protective action differs in cAMP and dibutyryl analogs of cyclic nucleotides, depending on the chemical structure of an embryotoxic substance. It is suggested that, endogenous intracellular "prenervous" transmitters and cyclic nucleotides are interrelated in the regulation of cell division in urchin embryos.

Animals↗
PubMed1984

[Adrenergic and cholinergic innervation of the normal human gallbladder and in various diseases].

As demonstrate investigations of the human gallbladder neural elements, normal (15 persons), after cholecystectomy resulted from dyskinesia (9 cases), diseases of the gallbladder cervix (28 cases), chronic (263 cases) and acute (16 cases) cholecystitis, using Falk--Hillarp--Govyrin, Karnovsky--Roots, Bielshowsky--Gros methods and incubation in 2% glyoxylin acid solution, a rich adrenergic and cholinergic innervation has been demonstrated in the organ studied at the states mentioned and their connection with the pathomorphological changes in the gallbladder wall. The analysis of 2,428 cases of chronic and acute cholecystitis has been performed in order to compare the clinical signs with changes in the central nervous system and the neural elements of the gallbladders removed. The importance of the gallbladder neural elements in the development of dyskinesia, diseases of the gallbladder cervix and chronic cholecystitis is mentioned.

Adrenergic Fibers↗
PubMedDate not supplied

[Adrenoreceptive structures in the early embryos of the clawed toad (Xenopus laevis)].

Studies have been made on the binding of labeled ligands to beta-adrenoreceptor--3H-dihydroalprenolol (DHA) and 125I-iodocyanopindolol (ICP--in crude homogenate and subcellular fractions of toad embryos during cleavage divisions. Specific binding of these ligands was observed which is confirmed by a decrease of the activity after addition of cold propranolol or adrenalin. The value of Kd for DHA is equal to 3 x 10(-9) M for ICP--to 1.5 x 10(-9) M. In addition to this high-affinity pool of binding with a low capacity, a low-affinity and high-capacity pool was also found. Cooling of the preparation up to 4 degrees C for 2 h increases the specific binding simultaneously with a decrease of the affinity of adrenoreceptive structures of the embryo. The data obtained are discussed in relation to the criteria of intracellular transmitter process.

Animals↗