Ultrastructural Study of the Age-dependent Effects of the Alendronate Sodium Hydrate Treatment on the Parathyroid Gland in Golden Hamsters

We examined the age-dependent effects of the alendronate sodium hydrate (alendronate) on the ultrastructure of the golden hamster parathyroid gland (PTG). At 1 year of age, the percent area of Golgi apparatus and lysosomes in alendronate-treated hamster PTG was significantly increased in comparison to control hamsters, while at 2 years of age, the percent area of lipid droplets was significantly decreased relative to control hamsters. These findings suggest that alendronate promotes the synthesis of hamster parathyroid hormone at 1 year but not 2 years of age. These results indicate that the sensitivity of PTG to alendronate is age-dependent.