Quantitative relationship of proline-rich proteins in whole, parotid and submandibular saliva

PLEASE NOTE: This work is protected by copyright. Downloading is restricted to the BU community: please click Download and log in with a valid BU account to access. If you are the author of this work and would like to make it publicly available, please contact open-help@bu.edu.Thesis (M.Sc.D.)--Boston University, Henry M. Goldman School of Graduate Dentistry (Oral Biology), 1981.Bibliography: leaves 45-49.The purpose of this study is to establish the quantitative relationship of salivary proline-rich proteins (PRPs) in human parotid, submandibular and whole saliva. A well characterized antiserum reacting only with the major and minor proline-rich proteins was used in modified double immunodiffusion method to determine the concentrations of proline-rich proteins in various salivary samples. The first experiment included stimulated whole, parotid and submandibular saliva specimens from 8 subjects exhibiting good to excellent periodontal health. The concentrations of PRPs in whole saliva ranged between 2.8-8.7 mg% whereas the concentration ranges of parotid and submandibular secretions were significantly higher with values of 17.8-83.7 mg% and 6.5-42.7 mg% respectively. In the second experiment the relationship between the strength of the stimulus and the PRP concentrations in parotid and submandibular secretions was evaluated using 5 different concentrations of citric acid applied to the lateral borders of the tongue in four subjects. Both flow rates and PRP concentrations showed considerable variations among individuals. With each subject, however, the stepwise increase of the stimulus strength from 0.1 to 0.5 M citric acid was concomitant with an increase in flow rates and PRP concentrations in both glandular secretions. At the weakest stimulus the parotid PRP concentrations ranged between 22.3-56.1 mg% whereas the corresponding range in submandibular saliva was 13.0-46.9 mg%. With the strongest stimulus these ranges increased to 43.9-87.3 mg% and 33.3-97.1 mg% for parotid and submandibular secretions respectively. The concentrations of PRPs in both major secretions appear to be quite similar under these conditions. In the third experiment micro samples of saliva were obtained in situ from the orifice of Stenson's duct,the cheek mucosa,the vestibular fold and again the vestibular fold after a single quick closure of the mouth. The concentrations of PRPs showed a rapid drop with the exposure to the oral environment. Samples from the vestibular exhibited a 25-75% reduction in concentration before closure and showed an even faster drop to values of 3 mg% or below after closure. The clear reduction of PRP concentrations after contact with oral surfaces explains in part the lower concentrations of PRPs in whole saliva when compared to their high concentrations measured in parotid and submandibular secretions