Age-related alteration of taste bud distribution in the common marmoset.

Alteration in the number of taste buds on the soft palate (SP), fungiform (FF), foliate (FL) and circumvallate (CV) papillae in the common marmoset at different postnatal ages was examined histologically. After paraffin embedding, complete serial sections at 10 microm thickness were made and stained by HE. Digitized images for each section were examined carefully. The number of FF taste buds at day 1 was 334. While only 20% of all the taste buds at birth possessed a taste pore, 39% of 174 SP taste buds at day 1 possessed a taste pore. The number of taste buds with pores at day 1 was small for the center CV (19 of 59), one side CV (7 of 25), and one side FL (2 of 16). These results suggest that the functional maturation of SP taste buds may precede maturation in other areas of the tongue. The total number of taste buds increased with increasing age, reached a maximum at 2 months of age: FF, 1069; SP, 609; CV-center, 530; CV-side, 390; FL, 201, and decreased thereafter. Almost all taste buds possessed a taste pore after 2 months of age. The decrease in the number of taste buds in the oral cavity with increase in age may change taste sensitivity.