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Biomedical subjects

N V Maksimova

Publications and source records attributed to N V Maksimova.

10 recordsLinked to original sources
PubMed2005

Role of viscosity and permeability of the erythrocyte plasma membrane in changes in oxygen-binding properties of hemoglobin during diabetes mellitus.

Changes in viscosity and permeability of the plasma membrane and conformation of erythrocyte hemoglobin hematoporphyrin were found in patients with diabetes mellitus. The decrease in oxygen binding and increase in deoxyhemoglobin concentration during diabetes mellitus were accompanied by changes in viscosity and permeability of the membrane for Na+, H+, Ca2+, and K+. Our results suggest that oxygen-binding properties of hemoglobin depend on viscosity and permeability of the erythrocyte plasma membrane.

Calcium↗
PubMed2002

Role of ionic transport in regulation of hemoglobin affinity for oxygen in diabetes mellitus.

The rate of Na(+)/H(+) exchange is increased by 24%, activities of Ca-dependent K+ channels is increased by 13%, and activity of erythrocyte Ca(2+)-ATPase decreased by 17% in patients with diabetes mellitus concomitant with essential hypertension in comparison with patients with essential hypertension without disorders of carbohydrate metabolism. Changes in activity of Na(+)/H(+) exchange, Ca-dependent K(+) channels, and erythrocyte Ca(2+)-ATPase and increased oxygen affinity of hemoglobin are due to increased glucose concentration in the plasma and are leveled by olifen.

Calcium-Transporting ATPases↗
PubMed2001

Study on conformational changes in hemoglobin protoporphyrin in essential hypertension.

Changes in protoporphyrin conformation, partial pressures of O2 and CO2, and the mechanisms responsible for regulation of pCa and pH in erythrocytes were studied in essential hypertension (EH). Changes in protoporphyrin conformation in EH were accompanied by a decrease in the partial pressure of O2 and an increase in the partial pressure of CO2. This was associated with increased activities of Na+/H+-exchange and Ca2+-dependent K+-channels and with a decreased activity of Ca2+-ATPase. The changes in protoporphyrin conformation in EH are suggested to decrease the efficiency of O2 metabolism in hemoglobin and increase the values of intracellular pCa and pH of erythrocytes.

Calcium-Transporting ATPases↗
PubMed1999

Efflux of cyclic adenosine monophosphate from cells: mechanisms and physiological implications.

Although cyclic nucleotides are hydrophilic compounds, extracellular cAMP (cAMPo) rapidly accumulates during the activation of adenylate cyclase. This review considers the kinetic characteristics of cAMP transport through the plasma membrane and its physiological implications. The influx and efflux of cAMP occur via different carriers. At physiological concentrations of cAMPo, the influx of cAMP does not significantly contribute to regulation of the intracellular content of the cyclic nucleotide, but it is responsible for the accumulation of cAMPi in experiments at [cAMP]o approximately 1 mM. In contrast, the high rate of cAMP efflux is mainly responsible for normalization of [cAMP]i during long-term activation of adenylate cyclase. The possible involvement of ATP-binding cassette proteins (ABC proteins) in the efflux of cAMP from the cell is considered. In procaryotes cAMPo is a signal molecule during the generation of cell colonies, acting on special receptors that interact with GTP-binding proteins. Such receptors have not been found in vertebrates, and in most cases the signal functions of cAMPo are mediated by its degradation by extracellular enzymes with subsequent activation of adenosine receptors.

Animals↗
PubMed1993

[Familial and nonfamilial forms of arterial hypertension].

Family and nonfamily hypertension (FH, NFH) forms were studied among patients with essential hypertension and symptomatic hypertension. Na-Li countertransport in FH patients against NFH ones proved significantly increased. However, CA2+ velocity mediated by Ca ATPase in them was less than in NFH subjects. Plasma filtration and hemosorption reduced arterial pressure more effectively in NFH patients. Surgical treatment in patients with symptomatic arterial hypertension is more successful in reducing arterial pressure in NFH subjects.

Adult↗
PubMed1993

[The recording of maximal Ca-ATPase activity in intact human erythrocytes by using a Ca-selective electrode].

The method for recording Ca-ATPase activity in intact erythrocytes was devised. The parameters of Ca2+ efflux, mediated by Ca-ATPase were investigated in Ca(2+)-loaded red blood cells, using Ca(2+)-selective electrode. The red blood cell calcium concentration was modified using the ionophore A23187 in Ca(2+) medium. Recording Ca efflux from RBC may be used as a routine method for the differential diagnosis of patients with essential hypertension and other forms of cell pathology.

Biological Transport↗