Development and maturation of taste buds of the palatal epithelium of the rat: Histological and immunohistochemical study
Open Access
- 16 May 2001
- journal article
- research article
- Published by Wiley in The Anatomical Record
- Vol. 263 (3) , 260-268
- https://doi.org/10.1002/ar.1095
Abstract
Palatal taste buds are intriguing partners in the mediation of taste behavior and their spatial distribution is functionally important for suckling behavior, especially in the neonatal life. Their prenatal development has not been previously elucidated in the rat, and the onset of their maturation remains rather controversial. We delineated the development and frequency distribution of the taste buds as well as the immunohistochemical expression of α‐gustducin, a G protein closely related to the transduction of taste stimuli, in the nasoincisor papilla (NIP) and soft palate (SP) from the embryonic day 17 (E17) till the postnatal day 70 (PN70). The main findings in the present study were the development of a substantial number of taste pores in the SP of fetal rats (60.3 ± 1.7 out of 122.8 ± 5.5; mean ± SD/animal at E19) and NIP of neonatal rats (9.8 ± 1.0 out of 44.8 ± 2.2 at PN4). α‐gustducin‐like immunoreactivity (‐LI) was not expressed in the pored taste buds of either prenatal or newborn rats. The earliest expression of α‐gustducin‐LI was demonstrated at PN1 in the SP (1.5 ± 0.5 cells/taste bud; mean ± SD) and at PN4 in the NIP (1.4 ± 0.5). By age the total counts of pored taste buds continuously increased and their morphological features became quite discernible. They became pear in shape, characterized by distinct pores, long subporal space, and longitudinally oriented cells. Around the second week, a remarkable transient decrease in the total number of taste buds was recorded in the oral epithelium of NIP and SP, which might be correlated with the changes of ingestive behaviors. The total counts of cells showing α‐gustducin‐LI per taste bud gradually increased till the end of our investigation (14.1 ± 2.7 in NIP and 12.4 ± 2.5 in SP at PN70). We conclude that substantial development of taste buds began prenatally in the SP, whereas most developed entirely postnatal in the NIP. The present study provides evidence that the existence of a taste pore which is considered an important criterion for the morphological maturation of taste buds is not enough for the onset of the taste transduction, which necessitates also mature taste cells. Moreover, the earlier maturation of palatal taste buds compared with the contiguous populations in the oral cavity evokes an evidence of their significant role in the transmission of gustatory information, especially in the early life of rat. Anat Rec 263:260–268, 2001.Keywords
This publication has 18 references indexed in Scilit:
- Monoclonal antibodies against recombinant parts of the Ki‐67 antigen (MIB 1 and MIB 3) detect proliferating cells in microwave‐processed formalin‐fixed paraffin sectionsThe Journal of Pathology, 1992
- Postnatal development of palatal and laryngeal taste buds in the hamsterJournal of Comparative Neurology, 1990
- Papilla palatina, Nasopalatine Duct and Taste Buds of Young and Adult RatsCells Tissues Organs, 1987
- The neural activities of the greater superficial petrosal nerve of the rat in response to chemical stimulation of the palateChemical Senses, 1986
- Quantitative taste bud distribution in the hamsterPhysiology & Behavior, 1984
- Fetal development of primate chemosensory corpuscles. I. Synaptic relationships in late gestationJournal of Comparative Neurology, 1983
- Taste bud distribution and innervation on the palate of the ratChemical Senses, 1982
- The ontogeny of feeding in rats: IV. Taste development as measured by intake and behavioral responses to oral infusions of sucrose and quinine.Journal of Comparative and Physiological Psychology, 1981
- A Cineradiographic Study of Breast FeedingThe British Journal of Radiology, 1958
- Ueber die Verbreitung der Geschmacksknospen beim MenschenVirchows Archiv, 1875