Effects of Pressure on Bone Resorption in the Middle Ear of Rats

Abstract
Laminaria, a hygroscopic seaweed, was used to induce pressure within the rat tympanic cavity. Resorption of the bulla and cochlear walls occurred in all animals within 2 weeks. Cochlear fistulas were observed in four of nine animals after 2 weeks and in nine of 11 aminals after 3 weeks. Preswelled laminaria inserted in the same area induced minimal bone resorption after 2 and 3 weeks. In animals given indomethacin following insertion of laminaria, both granulation-tissue formation and bone resorption were inhibited. Collagenase appeared localized in the inflammatory granulation tissue in the bone-resorption area, especially in fibroblasts, mononuclear cells, and osteoclasts. Results of this study suggested that pressure created by laminaria caused bone resorption by stimulating osteoclasts and granulation tissue.

This publication has 14 references indexed in Scilit: