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V N Iartsev

Publications and source records attributed to V N Iartsev.

10 recordsLinked to original sources
PubMed2004

[Effects of exogenic noradrenaline and melatonin on the neurogenic vasoreactivity].

The effect of 0.1 microM noradrenaline and melatonin on the response to electrical field stimulation (EFS) of the juvenile rat artery segment was studied. Noradrenaline like melatonin was shown to potentiate the EFS-evoked constriction decreased in the course of experiments or in the acidic solution (pH 6.6), and this potentiation was proportional to the extent of the preceding decrease of the constriction. The effect of these substances was additive. The results suggest that noradrenaline as well as melatonin can serve as a means to restore the diminished neurogenic reactivity of blood vessels.

Animals↗
PubMed2003

[Effect of melatonin on neurogenic vasoreactivity: formation and modulation of the vessel response].

The effect of melatonin (0.1 microM) on the contractile response to electrical field stimulation (EFS) of the juvenile rat tail artery segment was studied. The spontaneous decrease in reactivity of the segment observed in the course of our experiments was accompanied with a melatonin-evoked increase in the reactivity which was proportional to this decrease and was not connected with a sensitization of the segment to the substance. Perfusion of the segment with an acidic solution leads to a more pronounced inhibition of the response as well as to a greater melatonin-evoked protentiation of the response. Noradrenaline-evoked response was not augmented by melatonin. The results suggest that the potentiating effect of melatonin on the EFS-evoked response of the juvenile rat tail artery depends on degree of the change in the artery reactivity and was not due to change in sensitivity of postjunctional membrane to noradrenaline.

Animals↗
PubMed2001

[Contractile function of vessel myocytes: dependence on the stretch magnitude].

The values of the optimal stretch for the maximal responses of the rat mesenteric artery ring to electrical field stimulation (FES) or noradrenaline as well as for the maximal myogenic responses, tone, and maximal changes in these responses produced by low pH and dynamic sinusoidal stretch of the vessel wall were compared. The findings show that the magnitude of stretch corresponding to the maximal effect depend on the character of responses, on the factor, and on the responses occurrence conditions.

Animals↗
PubMed2000

[Reactivity of blood vessels in vitro: the role of perfusate pH and the initial tone of myocytes].

In the rat mesenteric artery ring, acidic solution (pH 7.0) inhibited the electrical field stimulation (EFS)-evoked response in a wide range of stretch. Acidosis potentiated the EFS-evoked constriction of the ring precontracted with 0.5 mu noradrenaline. The EFS dilated rings precontracted with 0.7 mu noradrenaline in control solution but contracted it in the acidic solution. Tone-dependent mechanisms of the acidosis effects on the EFS-evoked responses are discussed.

Animals↗
PubMed1998

[Effect of solution pH on the reactivity of the isolated segment of the rat mesenteric artery subjected stretching of various degree].

Experiments on the rat mesenteric artery's segments at different degrees of its stretching showed no influence of acidosis or alkalosis on the vessel wall tension within a wide range of pH (7.8-6.6). Acidification of the solution (7.0 or 6.6) inhibited the vessel response to noradrenaline or electrical field stimulation (EFS). On the contrary, the acidification potentiated a constriction caused by the EFS at a high level of vascular tone.

Animals↗
PubMed1985

[Changes in pulmonary ventilation after shafts in acid-base equilibrium in the skeletal muscles of the cat].

In anesthetized cats, perfusion of the m. gastrocnemius with solutions simulating metabolic acidosis produces a reflex enhancement of breathing proportional to the acidosis degree. Perfusion with solutions having pH 7.0, 6.8 and 6.3 induced 4.6 +/- 1.0, 6.3 +/- 0.5 and 10.3 +/- 1.2% increases of the minute volume of ventilation, resp. These increases were mainly due to increases of the tidal volume rather than of respiratory rate. An increase of the mean blood pressure also occurred whereas heart rate did not change significantly. Hindlimb perfusion experiments revealed that reflex changes of the blood pressure and breathing depended on the muscle mass perfused. Possible participation of the muscle receptors sensitive to changes of metabolism in exercise hyperpnea, is discussed.

Acidosis↗
PubMed1982

[Tissue chemoreceptors].

Intraarterial administration of acids or perfusion with solutions inducing acidosis in the small intestine tissue, increase the afferent impulsation in the splanchnic nerves as well as the arterial pressure in anesthetized cats. Threshold concentrations of lactic and carbonic acids don't exceed, at that, their normal contents in the blood and tissues. Similar data were obtained in perfusion of the small intestine with blood of a donor animal whose acid--alkaline balance (AAB) was altered. The tissue receptors were found to be more sensitive to the metabolic rather than respiratory acidosis, due to different alteration of of the intratissue pH. Sensitivity of the skeletal muscles' chemoreceptors proved somewhat lower as compared with the small intestine receptors. Nevertheless, the threshold shifts of the AAB parameters in the m. gastrocnemius perfusion developed within the normal range. The changes of minute volume of ventilation revealed the possibility of tissue receptors participation in the reflex control of respiration as well. The data on adequate sensitivity of the tissue receptors to terminal products of aerobic and anaerobic metabolism: carbonic and lactic acids, once more corroborate V. N. Tchernigosky's ideas of the tissue chemoreceptors as a special class of receptor structures providing the c.n.s. with necessary information on intensity of the tissue metabolism.

Acid-Base Imbalance↗
PubMedDate not supplied

[The effect of polarization of the vascular wall on the ion transport and contractile activity of the rat tail artery].

The effects of the blood velocity upon the responsiveness of blood vessels seem to be based on the processes inducing a deforming of the diffuse part of a double electrical layer at the border between the blood and vascular wall of the rat tail artery. Salts of polyvalent metals were found to diminish the negativity of the transmural potential and to diminish the contractile activity and the tone of the blood vessels. Heparin exerted an opposite effect.

Animals↗