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Biomedical subjects

R S Orlov

Publications and source records attributed to R S Orlov.

At least 55 records · Page 3Linked to original sources
PubMed1975

[Activation mechanisms for contractions of the smooth musculature of the cerebral vessels].

Pial arteries and veins were found to differ by their contractile features. Pial arteries are highly sensitive to noradrenaline, adrenaline, histamine, serotonin, rapid stretching, and potassium ions. The effects of the mediators, potassium ions, and rapid stretching could be blocked by manganese ions. Pial veins are insensitive to the mediators effects, potassium ions, or rapid stretching, although they are highly sensitive to transmural electric stimulation. Manganese ions have no effect on the veins' responses to electric stimulation. A spontaneous activity of the smooth muscle cells of the a. carotis' intracranial portion was revealed in man. The activation mechanisms for the cerebral arteries smooth muscle contractions are suggested to depend on the calcium extracellular ions. The activation mechanism for the veins' smooth muscle contractions depends on the intracellular store of calcium ions.

Acetylcholine↗
PubMed1975

[The contractile and electrical activity of the smooth muscles of the major lymph vessels].

In rats, catecholamines were found to increase the rate of the muscles spontaneous rhythmic contractions while the alpha- and beta-blocking agents suppressed them. The spontaneous contractions were blocked in the uncalunm medium. Rhythmic electrical stimulation evoked contracture-like responses the uncalunm of which depended on the strength, frequency, and duration of the stimulation. In spontaneoulsy active preparations, single electrical stimuli evoked contractions according to the "all or nothing" rule. The membrane potential magnitude varied within the limits of 25-37 mV, and action potentials were related to the contractions. The data obtained suggest that the functional unit of conduction of spontaneous or evoked excitation waves is represented by a group of smooth muscle cells within a single lymphangion.

Acetylcholine↗