Microanalysis of epithelial and mesenchymal acid hydrolase activities in the developing palate.

Microdissection of lyophilized sections of fetal heads permits the analysis of relatively pure samples of epithelium and mesenchyme. These techniques were applied to a study of acid phosphatase and beta-glucuronidase activities in the developing palate in A/Jax mice. Acid phosphatase was found to be more concentrated in the palatal epithelium than the underlying mesenchyme. Conversely, beta-glucuronidase was more concentrated in the mesenchyme than the epithelium. A disparate developmental pattern of acid phosphatase and beta-glucuronidase activity was observed in the oral epithelium: acid phosphatase activity increased from intra-uterine Day 17 into neonatehood and beta-glucuronidase activity decreased towards term. Analysis of cortisone-induced palatal shelves showed increased activity of both acid phosphatase and beta-glucuronidase in the presumptive fusing epithelium.