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Taking into consideration the nanodimension of functional components of living cells, the application of nanotechnology in the biomedical purposes is currently an urgent task. One of these directions is the use of aluminum nanoparticles for molecular diagnostics, targeted delivery of drugs, the development of new pharmaceuticals. The action of aluminum chloride on the regulatory mechanisms of smooth and skeletal muscle contraction and also the effect of aluminum ions on the ATPase activity and superprecipitation of actomyosin of different types of muscles is discussed.

The effect of C60 fullerene aqueous colloid solution (C60FAS) on viscoelastic properties of human erythrocytes membrane has been studied. It was established that the effect of C60FAS on erythrocytes depends on the medium osmolality and concentration of C60 fullerene in it. In particular, in isotonic solution (0,15 mol/l NaCl) adding C60 fullerene in concentrations from 0,7 to 28 μmol/l did not cause the hemolytic damage of cells. In hypotonic medium when introducing C60 fullerene (7 μmol/l concentration) at the beginning of erythrocyte hemolysis its stimulating effect was maximal and when adding C60FAS in 20 s after hemolysis start no this process stimulation is observed. This points to the changes in viscoelastic properties of erythrocyte membranes even during the first seconds of its interaction with C60 fullerene.

The method is proposed for calculation of the most important parameters of the two-stage enzymatic or transport process--modification factors alpha and beta (which characterize the effector action mechanism) as well as the inhibition constant K(i) or activation constant K(a) (characterize the effector affinity for protein). The method was derived as based on the analysis of kinetic regularities of the action of reversible effectors (inhibitors and activators) on the catalytic (transport) activity of proteins. The method is based on the titration of enzymatic (transport) protein by the substrate with the absence and with presence of the effector taken in one of concentrations as well as determination (under the fixed substrate concentration) of the inhibition coefficient i(0.5) (in case of the inhibitor action) or the activation coefficient a(0.5) (in case of the activator action). Practical use of the method has been demonstrated on the example of reversible inhibition to eosine Y (2', 4', 5', 7' - tetrabromofluorescein) ofthe reaction of enzymatic hydrolysis of ATP catalyzed by highly purified transport Ca2+, Mg(2+)-ATPase isolated from the smooth-muscle sarcolemma. In this case the inhibitory effect is characterized by the following parameters: alpha = 6-8 > 1; beta = 0.50-0.53 < 1; inhibition constant K(i) = 10(-9) - 10(-8) M. Consequently, judging from the values of alpha and beta, the eosine Y effect on the analyzed Ca2+, Mg(2+)-dependent ATP-hydrolase enzymatic reaction is based on the mechanism of the mixed inhibition (one can observe the inhibition of the both stages of enzymatic transformation--the substrate binding with the enzyme and decomposition of "Michaelis complex" in the direction of formation of the reaction products). The inhibitor itself, in correspondence with K(ij) values is characterized by rather high affinity for Ca2+, Mg(2+)-ATPase. It is supposed that the proposed approach can be useful when identifying the type of the reversible effector action on the enzymatic (transport) activity of proteins, estimation of real affinity of the inhibitors and activators for the latter.

The influence of pH medium on ATP-ase activity of skeletal muscles myosin has been investigated. The mathematical simulation, which reflects the ATP-hydrolase biochemical reactions after pH medium changes in the muscular fiber was also carried out.

It was demonstrated in experiments made on a fraction of plasma membranes of the uterine smooth muscle cells that PH-dependence of enzymatic activity of the "basal" (Ca(2+)-independent) Mg(2+)-ATPase obtained under the conditions of determining the initial velocity of ATP hydrolysate is not bell-shaped but is characterized by linearity in the range of the values of hydrogen index 6.0-8.0. A kinetic model of Mg(2+)-dependent enzymatic hydrolysis of ATP has been suggested and analyzed; the model explains the linearity of the above pH-dependence. Results of kinetic analysis prove that the cause of linear pH-dependence of enzymatic activity of the "basal" Mg(2+)-ATPase is that the proton H+ is a competitive inhibitor of the given enzyme: the increase of protons concentration leads to a decrease of the affinity of Mg(2+)-ATP substrate for the enzyme, but it has no effect on the number of circulations of the latter. Thus the work gives a kinetic substantiation of the possible regulatory role of protons H+ as the factor of original negative inverse relation which controls the enzymatic activity of the basal Mg(2+)-ATPase "producing" protons in the myometrium cells; the concentration of protons in the near-membrane regions of the myoplasma being increased the ATPase activity decreases, and the former being decreased the latter increases. It is not excluded that owing to its original linear pH-dependence the studied ATP-hydrolase system serves as an important element of the control of proton homeostasis in the smooth-muscle cells.

The mathematical model of smooth muscles contractile activity Ca(2+)-dependent control has been proposed on the base of Ca ions trans-sarcomal exchange biochemical mechanisms interpretation in myocytes. While analysing the model the conclusion should be made that kinetic parameters changes (in relation to Ca ions) Mg2+, ATP-dependent calcium pump of plasma membrane--Michaelis constant Km and transport process maximal velocity Vmax-render the effect on the character of the intracellular calcium transients and profile of full mechanokinetic curve. As well one more conclusion has been made that plasma membrane Mg2+, ATP-dependent calcium pump, which kinetic parameters under the physiologic conditions are subjected to modulation as the result of metabolic, pharmacologic and physico-chemical factors fulfills the essential role in supplying Ca(2+)-dependent control of the smooth muscles contractile response full cycle.