Effects of cadmium acetate and sodium selenite on mucociliary functions and adenosine triphosphate content in mouse trachea organ cultures

Abstract

The effects of cadmium acetate and sodium selenite in mouse trachea organ culture have been studied separately and in combination. Ciliary activity, morphology, rate of total protein and glycoconjugate (i.e. glycoprotein and proteoglycan) synthesis/secretion and ATP content were investigated. Exposure to 10 μM cadmium acetate or 2000 μM sodium selenite resulted in a complete cessation of ciliary activity within 5 h. With cadmium acetate also a swelling of epithelial cells was observed. Sodium selenite (250–2000 μM) delayed by 2–3 h the inhibitory effect of cadmium acetate (5–20 μM) on ciliary activity. The rate of protein synthesis, as determined by incorporation of [ 3H] proline, was reduced by 13% and 44% at exposure for 4 h at 37°C to 250 μM and 500 μM sodium selenite respectively, the effect being partly abolished by cadmium acetate. With 5 μM and 10 μM cadmium acetate the rate of glycoconjugate synthesis, as measured by incorporation of [ 3H] glucosamine, increased by 50% and 69%, respectively, after incubation for 4 h. This increase was partly reduced by sodium selenite. Neither cadmium acetate nor sodium selenite had any effect on the rate of total protein or glycoconjugate secretion. The ATP content in trachea rings was reduced by 48% and 54% after incubation for 4 h with 250 μM and 500 μM sodium selenite, respectively. No significant effect of cadmium acetate was found on ATP content. An antagonistic effect of sodium selenite and cadmium acetate in mouse trachea organ culture is suggested from the present experiments.