Structure of the soft palate and composition of the oral mucous membrane in monkeys

Abstract

The soft palate of monkeys (M. irus, mulatta, fasciculata; 2.3 +/- 0.4 kg in weight) was studied morphologically and stereologically. After fixation by perfusion, the tissue was disected free, divided in halves and the halves into 5 segments each, and processed for light, transmission- and scanning electron microscopy. Morphometric techniques and a newly developed computer program for automatic data processing (Mumana) were employed in order to estimate, at the light microscopic level, the volumetric composition of the oral soft palate mucosa. The latter showed a different composition in anterior and uvular segments, without significant differences between male and female animals, but with slight changes possibly due to age. The main constituents of the oral soft palate mucosa were glandular and connective tissue, and lymph follicles, the latter being associated with the glandular duct system. The epithelial lining of the oral and nasal aspects were described, and taste buds embedded in island of orthokeratinizing stratified epithelium were demonstrated. The association between lymph follicles and the glandular duct system was discussed in relation to similar structures in man, and in relation to the hypothesis that they are concerned in local antigen recognition.