Histochemical and biochemical properties of the labial and palatine glands and their secretions in the Macaca irus and Cercopithecus aethiops monkeys.

The increasing use of non-human primates in experimental studies in dentistry demands detailed knowledge of their basic oral biology. The labial and palatine glands and their secretory products were compared in two commonly used monkey species. The mucous cells of both gland types appeared to elaborate sulphated muco-substances and the serous demilunes of the labial glands neutral mucosubstances. The secretions of these glands, as obtained by in vitro cultivation of glandular tissue were subjected to isoelectric fractionation. The labial and palatine secretions of the C. aethiops contained an acidic component which exhibited the viscous properties of the original secretions, showed incorporation of 35SO4 and had high titres of virus-haemagglutination inhibition activity. A similar component has been found in M. irus labial and palatine secretions. The two monkey species were similar in that the labial gland secretions of both contained small amounts of lysozyme activity, which the palatine gland secretions did not. They differed in that alpha-amylase activity was present in the labial and palatine secretions of the C. aethiops, which corresponds to the human situation. The minor glands of the M. irus did not show traces of alpha-amylase activity. The distribution of several chemical characteristics of the salivary gland secretions of both monkey species indicated that neither of them were identical to man, even though a general similarity was evident.