Nanochemistry and biotechnology

Aqueous nanocolloids of zinc oxide. Motility state of the gastrointestinal tract and hepatobiliary system of the rats
Tsymbalyuk O.V.1, Davydovska T.L.1, Lisnyak V.V.2,3, Veselsky S.P.1, Zaderko A.N.1,4, Voyteshenko I.S.1, Naumenko A.M.1, Skryshevsky V.A.1,4
1 Institute of High Technologies, Taras Shevchenko National University of Kyiv. 64, Volodymyrska Str., 01601 Kyiv, Ukraine. 
E-mail: ganna.naumenko@gmail.com
2 Chemical Faculty, Taras Shevchenko National University of Kyiv, 64, Volodymyrska Str., 01601 Kyiv, Ukraine.
3 Prešov University in Prešov, Ul. 17. Novembra č. 1, 081 16 Prešov, Slovakia. 
4 Corporation Science Park, Taras Shevchenko National University of Kyiv, 60, Volodymyrska Str., 01033 Kyiv, Ukraine.

The TEM/HRTEM methods were used in our work to confirm the application of the ZnO aqueous nanocolloids, which differ from the solutions of Zn2+ ions. Using the tenzometric method it was demonstrated that under in vivo conditions the burdening of the rats with ZnO aqueous nanocolloids for 30 and 100 days was accompanied with the impairment in the mechanisms of regulating of the spontaneous contractions of the antrum and the caecum smooth muscles: the changes in the amplitude ranges, asymmetry coefficients, indices of functioning efficiency, frequency of spontaneous contractions, contraction-relaxation velocities. It was also found that the sensitivity to the effect of the ZnO aqueous nanocolloids was mainly demonstrated by М2-receptor-dependent mechanisms of regulating intracellular concentration of Са2+ ions in the smooth muscle cells. The mechanisms of Ca2+-induced release of Ca2+ from the sarcoplasmic reticulum of smooth muscle cells were insensitive to the effect of ZnO aqueous nanocolloids. The method of molecular docking of ZnO nanoparticles with muscarinic M2 and M3 type receptors demonstrated that they did not compete with acetylcholine for binding sites, but could impact the affinity of orthosteric ligands to M2 cholinoreceptors, which might result in blocking the access of the agonist to its binding site. Under burdening of the rats with ZnO aqueous nanocolloids there were also changes in biochemical markers for the liver function, enzyme activity of the primary active ion transport in plasma membranes of erythrocytes.