Selenium is known to play an important role in the physiology of many cell types and extracellular application of high concentration (1 mM and higher) of sodium selenite causes cellular dysfunction in different types of mammalian tissues. In the present study, we aimed to investigate the effects of sodium selenite (1 mM) application on the contractile activity of isolated rat ileum. We also investigated the effect of diltiazem and atropin application on these contractions.

Adult Wistar rats (200-250 g) were used. Isolated ileum contractility was measured by using convential organ bath system with Tyrode perfusion solution. All contractions were given as percentage changes. Sodium selenite application (15 min) caused a very significant (p<0.001) incrase (230±55%) in the ileal contraction. Both diltiazem and atropin enhanced this contraction significantly (p<0.001) in the same order (280±34% and 275±49%, respectively). On the other hand, acetylcholine did inhibite this sodium selenite-induced contraction in the order of 43±14%.

Selenium, to be a multifunctional trace element, can show different types of effects mostly due to tissue, dose, or time dependency. This hypothesis is supported with many studies even including our studies. [Idot]n smooth muscle preparations such as ileum, it caused enhancement of contractile response. On the other hand, enhancement mechanisms of the ileal sodium selenite-induced responses with both diltiazem and atropin are not clear yet and this subject should be under further investigation.