Transient increase of TUNEL-positive cells on postnatal day 20 in the developing rat olfactory bulb.
In the developing central nervous system, apoptosis plays an important role in the normal organization of the neuronal circuit. The timing of neurogenesis, proliferation, and migration of the neurons in the developing olfactory bulb (OB) is well studied; however, the involvement of apoptosis in this process is not fully understood. In this study, we examined the changes in the distribution and the number of apoptotic cells in the rat OB during embryonic and postnatal periods, by using terminal deoxynucleotidyl transferase-mediated dUTP-digoxigenin nick end-labeling (TUNEL) staining. Although the number of TUNEL-positive cells was relatively small during the embryonic period, it gradually increased after birth, and peaked on postnatal day 20 with statistical significance, especially in the granule cell layer of the main OB. This transient increase of TUNEL-positive cells on postnatal day 20 may be involved in a critical event during maturation of the OB.
Saito
Kyoko
K
Division of Anatomy and Embryology, Department of Integrated Basic Medical Science, School of Medicine, Ehime University, Shitsukawa, Shigenobu-cho, Onsen-gun, Ehime 791-0295, Japan.
Saito
Shouichiro
S
Taniguchi
Kazuyuki
K
Kobayashi
Naoto
N
Terashita
Takehiro
T
Shimokawa
Tetsuya
T
Mominoki
Katsumi
K
Miyawaki
Kyojy
K
Chen
Jie
J
Gao
Shuang-Yan
SY
Li
Chun-Yu
CY
Matsuda
Seiji
S
D000818:Animals; D000831:Animals, Newborn; D017209:Apoptosis / Q000502:physiology*; D002452:Cell Count; D005260:Female; D005333:Fetus; D020287:In Situ Nick-End Labeling; D008297:Male; D009474:Neurons / Q000166:cytology*; D009830:Olfactory Bulb / Q000254:growth & development*; D051381:Rats; D017208:Rats, Wistar