Proline-rich proteins contribute about 70% of the proteins in human parotid saliva. Observations in this laboratory, coupled with those from other laboratories, suggest a stong negative correlation between basic proline-rich proteins in the parotid saliva of rats and caries susceptibility. Very little is known about factors which influence the synthesis of these unique salivary proteins. The long-term objectives of this project have been to study factors which contribute to their regulation. Observations to date in this laboratory, coupled with the findings in other laboratories, suggest that alterations in b-adrenergic receptors lead to parallel changes in the proportion of proline-rich proteins in rat parotid saliva. Thus, the present proposal was designed to study this apparent relationship. The two specific aims are (I) to test the hypothesis that changes in the proportion of proline-rich proteins in rat parotid saliva are associated with parallel disproportionate changes in b-receptor density or biologic activity and (II) to determine at what stage of postnatal development of the rat parotid gland proline-rich proteins appear. A delay in their appearance until b-receptors exhibit biologic activity would support the hypothesis. In these studies the proportion of proline-rich proteins in parotid saliva will be correlated with b-receptor density or biologic activity. The composition of proteins will be determined by densitometric scanning of color positives taken of acrylamide gels following SDS-PAGE. These findings will be correlated with studies which test the biologic activity of the b-receptors as well as their density. The former involves in vitro assays of the ability of receptors to respond to an appropriate stimulus; the latter involves radioligand binding studies for quantitation of numbers of receptors. The proposed work may result in a better understanding of factors which regulate this unique group of salivary proteins.

Agency
National Institute of Health (NIH)
Institute
National Institute of Dental & Craniofacial Research (NIDCR)
Type
Research Project (R01)
Project #
5R01DE006000-06
Application #
3219723
Study Section
Oral Biology and Medicine Study Section (OBM)
Project Start
1981-06-01
Project End
1988-05-31
Budget Start
1986-06-01
Budget End
1987-05-31
Support Year
6
Fiscal Year
1986
Total Cost
Indirect Cost
Name
University of Texas Health Science Center San Antonio
Department
Type
Schools of Dentistry/Oral Hygn
DUNS #
800772162
City
San Antonio
State
TX
Country
United States
Zip Code
78229
Johnson, D A; Lopez, H; Navia, J M (1995) Effects of protein deficiency and diet consistency on the parotid gland and parotid saliva of rats. J Dent Res 74:1444-52
Johnson, D A; Cardenas, H L (1993) Effects of food mastication on rat parotid gland adrenergic and cholinergic cell surface receptors. Crit Rev Oral Biol Med 4:591-7
Johnson, D A; Kalu, D N (1988) Influence of thyroxine in the regulation of rat parotid salivary protein composition. J Dent Res 67:812-6
Johnson, D A (1988) Changes in rat parotid saliva protein composition following chronic reserpine treatment and their relation to inanition. Arch Oral Biol 33:463-6
Johnson, D A; Cortez, J E (1988) Chronic treatment with beta adrenergic agonists and antagonists alters the composition of proteins in rat parotid saliva. J Dent Res 67:1103-8
Johnson, D A; Alvares, O F; Etzel, K R et al. (1987) Regulation of salivary proteins. J Dent Res 66:576-82
Johnson, D A; Etzel, K R; Alvares, O F et al. (1987) Regulation of parotid salivary proteins by glucocorticoids. J Dent Res 66:1563-8