Transient Bax-protein immunoreactivity prior to apoptosis of spiral ganglion neurons in the postnatal rat.
The apoptosis occurring in the postnatal developing spiral ganglion cells (SGCs) and the concomitant change in Bax-protein immunoreactivity were investigated in rats at postnatal days (P) 1, 3, 5, 7, 10 and 14, and also in adult rats. In P5 and P7 rats, some neurons showed structural features of apoptosis, including cell shrinkage, condensed chromatin around the margin of the nucleus and phagocytosis of apoptotic bodies by satellite cells. The percentage of Bax-protein-positive neurons in the spiral ganglion was significantly higher in P1, P3, P5, and P7 rats compared with adult rats. Our results confirm the occurrence of neuronal cell apoptosis in the spiral ganglion at the end of the first postnatal week, and demonstrate the transient change in Bax-protein immunoreactivity prior to neuronal cell apoptosis. Thus, we speculate that the transient change in Bax protein could be involved in neuronal cell apoptosis of the postnatal developing SGCs of rats.
Wang
Z
Z
Department of Otolaryngology, EENT Hospital, Shanghai Medical University, People's Republic of China. zmwang@shmu.edu.cn
Li
H
H
Chi
F
F
Li
H
H
Shen
Y
Y
D000818:Animals; D017209:Apoptosis; D005260:Female; D018072:Hair Cells, Auditory, Outer / Q000378:metabolism; D008297:Male; D011518:Proto-Oncogene Proteins / Q000276:immunology* / Q000378:metabolism; D019253:Proto-Oncogene Proteins c-bcl-2; D051381:Rats; D017207:Rats, Sprague-Dawley; D013136:Spiral Ganglion / Q000378:metabolism / Q000648:ultrastructure*; D051028:bcl-2-Associated X Protein
C494828:Bax protein, rat; D011518:Proto-Oncogene Proteins; D019253:Proto-Oncogene Proteins c-bcl-2; D051028:bcl-2-Associated X Protein