EC Pharmacology and Toxicology

A Polymethylsilsesquioxane-zinc™ sorbent (PSS-Zn) is capable of dose-dependently inhibiting spontaneous autorhythmic activity and dose-dependently relaxing isolated segments of guinea pig Taenia coli, pre-activated with a high concentration of potassium chloride. This effect can be considered a manifestation of PSS-Zn's potential antidiarrheal properties. The relaxing effect of the dimethyl sulfoxide (DMSO) solvent on Taenia coli segments was insignificant at all doses, except for the maximum solvent concentration of 1 mg/ml. Thus, it can be concluded that it is the PSS-Zn sample itself, and not its DMSO solvent, that exerts the antidiarrheal (relaxing) effect. When the PSS-Zn sample was added to the tissue bathр solution simultaneously with acetylcholine, an increase, rather than a decrease, in Taenia coli smooth muscle activity was observed. Therefore, it can be assumed that the antidiarrheal (dilating) properties of PSS-Zn are not related to its effect on acetylcholine receptors. Given that PSS-Zn is capable of relaxing Taenia coli segments previously constricted by a potassium chloride solution (60 mmol), the relaxing effect of the studied PSS-Zn samples is likely due to blockade of calcium ion entry through voltage-gated calcium channels or its direct calcium-binding action.

 Keywords: Taenia coli; Diarrhea; Smooth Muscle Contractile Activity; Polymethylsilsesquioxane-Zinc™-Based Sorbent

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