title: Aging affects morphology but not stimulated secretion of saliva in rats.
abstract: BACKGROUND
  The role of aging on the salivary gland function still remains controversial and inconclusive. This study was undertaken to determine the effects of aging on the morphology and secretion of salivary glands using male Wistar rats.
  
  
  METHODS
  There were three age groups; group A (3 months old; n = 8), group B (6 months old; n = 8), and group C (9 months old; n = 8). Body weights, salivary gland weights, salivary flow rates, pH and salivary levels of sodium, potassium, calcium, chloride, bicarbonate, phosphate and total protein were measured and compared. Hematoxylin-eosin stained histological slides of the salivary glands were assessed for morphological changes.
  
  
  RESULTS
  Body weights increased with age while mean parotid gland weight was significantly higher in group B than in groups A and C. Mean salivary flow rate was significantly higher in group B and C than in group A, and mean salivary pH was significantly higher in group B and C than group A. Analysis of salivary electrolytes and total protein showed that mean levels of sodium, potassium and bicarbonate increased with age significantly while mean levels of calcium, chloride, phosphate and total protein did not show significant change among the groups.
  
  
  CONCLUSIONS
  These findings showed that varying changes were observed in the morphology of salivary glands of aging rats without impaired function.
authors.affiliation: Department of Physiology, College of Medicine, University of Ibadan, Ibadan, Nigeria ; Department of Oral Pathology, College of Medicine, University of Ibadan, Ibadan, Nigeria.
authors.forename: T J
authors.initials: TJ
authors.lastname: Lasisi
authors.affiliation: Department of Physiology, College of Medicine, University of Ibadan, Ibadan, Nigeria.
authors.forename: S T
authors.initials: ST
authors.lastname: Shittu
authors.affiliation: Department of Physiology, College of Medicine, University of Ibadan, Ibadan, Nigeria.
authors.forename: M M
authors.initials: MM
authors.lastname: Oguntokun
authors.affiliation: Department of Physiology, College of Medicine, University of Ibadan, Ibadan, Nigeria.
authors.forename: N A
authors.initials: NA
authors.lastname: Tiamiyu
keywords: Aging; Salivary Glands; Salivary electrolytes; Salivary flow rates; Salivary total protein