Journal of Dental Research, Vol 67, 565-573, Copyright © 1988 by International & American Associations for Dental Research Online Journals
Age changes in secretory function of male and female rat parotid glands in response to methoxamine and pilocarpine
A. Inanaga, T. Habu, E. Tanaka, T. Taniguchi, T. Nishiura, K. Ishibashi, S. Naruse and K. Abe
First Department of Prosthodontics, Fukuoka Dental College, Japan.
Saliva secreted in response to methoxamine and pilocarpine was collected
from the cannulated ducts of both parotid glands of male and female rats at
weekly age intervals from three to 10 weeks, and at 3.5, 8, and 15 months
of age. It was analyzed for the concentrations of protein, potassium,
calcium, inorganic phosphate, and for amylase activity. The type of protein
were determined electrophoretically, and an amino acid analysis of the
total protein was also carried out. The wet weights of the glands increased
substantially up to eight weeks of age, then reached almost plateau values,
and finally tended to decrease at 15 months of age in both sexes. The
salivary volumes secreted in response to methoxamine and pilocarpine were
positively correlated with the parotid gland weights in both sexes. The
concentrations of protein, potassium, and inorganic phosphate were
inversely related to the salivary flow rates only at relatively low rates
of flow. The amylase activity was positively correlated with the
concentration of protein, independent of the nature of the stimulus, age,
and sex. With methoxamine as a stimulus, the amylase activity was
positively correlated with the concentration of calcium, independent of age
and sex. The types of protein and amino acid concentrations were
independent of the nature of the stimulus, age, and sex up to 15 months of
age. However, in parotid saliva of several rats at 8 and 15 months of age,
unusual proteins were observed electrophoretically, independent of the
nature of the stimulus and sex.
