Tag Archives: colon

The heterogeneity of the Na(+),K(+)-ATPase ouabain sensitivity in microsomal membranes of rat colon smooth muscles

A. A. Kaplia

Palladin Institute of Biochemistry, National Academy of Sciences of Ukraine, Kyiv;
е-mail: kaplya@biochem.kiev.ua

The dose dependence of the Na+,K+-АТРase ouabain inhibition in the rat colon smooth muscle permeabilized microsomes has been analyzed according to the model of two independent binding sites of inhibitor to determine the activity of separate molecular forms of the enzyme that differ by affinity for cardiac glycosides. The two-phase inhibition curve with moderate content of the high-affinity activity component was revealed. The apparent inhibition constant of the low-affinity component corresponds to the value for the rat kidney microsomal Na+,K+-АТРase (α1-isoform). The specific role of the α2- and α1- Na+,K+-АТРase catalytic subunit isoforms in colonic smooth muscle electromechanical coupling is considered.

Fecal short-chain fatty acids at different time points after ceftriaxone administration in rats

Yu. V. Holota1, O. O. Holubenko2, A. M. Ostapchuk2,
T. M. Serhiychuk1, L. V. Zakordonets3, G. M. Tolstanova1

1Educational and Scientific Center “Institute of Biology and Medicine”,
Taras Shevchenko National University of Kyiv, Ukraine;
2D.K. Zabolotny Institute of Microbiology and Virology, National
Academy of Sciences of Ukraine, Kyiv;
3Bogomolets National Medical University, Kyiv, Ukraine
е-mail: gtolstanova@gmail.com

Short-chain fatty acids (SCFAs) are major products of the microbial fermentation of dietary fiber in the colon. Recent studies suggest that these products of microbial metabolism in the gut act as signaling molecules, influence host energy homeostasis and play major immunological roles. In the present study, defined the long-term effects of ceftriaxone administration on the fecal SCFAs concentration in Wistar rats. Ceftriaxone (300 mg/kg, i.m.) was administered daily for 14 days. Rats were euthanized in 1, 15 and 56 days after ceftriaxone withdrawal. Caecal weight and fecal concentration of SCFAs by gas chromatography were measured. Ceftriaxone administration induced time-dependent rats’ caecal enlargement through accumulation of undigestable substances. In 1 day after ceftriaxone withdrawal, the concentrations of acetic, propionic, butyric acids and total SCFAs were decreased 2.9-, 13.8-, 8.5-, 4.8-fold (P < 0.05), respectively. Concentration of valeric, isovaleric and caproic acids was below the detectable level. That was accompanied by decreased 4.3-fold anaerobic index and increased the relative amount of acetic acid (P < 0.05). In 56 days, concentration of SCFAs was still below control value but higher than in 1 day (except propionic acid). Anaerobic index was lower 1.3-fold (P < 0.05) vs. control. Conclusion: antibiotic therapy induced long-term disturbance in colonic microbiota metabolic activity.