Effect of triethyl lead on peristaltic contractile activity of the ileum of mice.

The effect of triethyl lead (TriEL) as triethyl lead chloride on the rhythmic peristaltic contractile activity of ileum isolated from Swiss white mice was investigated, with the aid of a tensiometer. The response was measured as a change in period duration and force amplitude. TriEL concentrations of < 40 microM did not show any obvious effects on either of the parameters. In the concentration range between 40 and 120 microM, TriEL exclusively affected the rhythm of contractions in a concentration-dependent manner. It induced elongation of the period and reduction of the force amplitude. Concentrations of TriEL above 120 microM induced irreversible dramatic changes in the ileum contractile activity, while 200 microM TriEL induced a strong contracture followed by an irreversible cessation of the oscillatory contractile activity. The results demonstrate that the measurement of rhythmic contractions may be a useful model for a toxicological screening system.