Endoplasmic reticulum may not be involved in the lead-induced apoptosis in PC 12 cells in vitro.
Recent researches indicated that mitochondrial pathway might play an important role in lead-induced apoptosis. Our previous study also found that lead could induce apoptosis in PC 12 cells, and mitochondrial pathway events were involved in this process. As lead can disturb Ca(2+) homeostasis, the present study was undertaken to determine whether lead can activate key cellular events in the endoplasmic reticulum (ER) pathway, including the expressions of C/EBP homology protein (CHOP) and glucose-regulated protein 78 (GRP78), and the activation of caspase-12 and calpain. The results showed that lead could increase the expression of GRP78, while the expressions of CHOP and procaspase-12 remained unchanged. Moreover, the caspase-12 and calpain were not activated, and the ultrastructure of endoplasmic reticulum was not altered. Therefore, it suggests that lead may induce apoptosis in PC 12 cells through mitochondrial pathway, but not through the endoplasmic reticulum pathway.
Xu
Jin
J
Institute of Preventative Medicine, School of Medicine, Ningbo University, Ningbo, People's Republic of China.
Ji
Lin-Dan
LD
Xu
Li-Hong
LH
D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D002154:Calpain / Q000235:genetics / Q000378:metabolism; D053454:Caspase 12 / Q000235:genetics / Q000378:metabolism; D004721:Endoplasmic Reticulum / Q000187:drug effects* / Q000378:metabolism; D004789:Enzyme Activation; D005786:Gene Expression Regulation / Q000187:drug effects; D006360:Heat-Shock Proteins / Q000235:genetics / Q000378:metabolism; D009942:Organometallic Compounds / Q000633:toxicity*; D016716:PC12 Cells; D051381:Rats; D051742:Transcription Factor CHOP / Q000235:genetics / Q000378:metabolism; D000091342:Endoplasmic Reticulum Chaperone BiP
D002154:Calpain; D053454:Caspase 12; D006360:Heat-Shock Proteins; D009942:Organometallic Compounds; D051742:Transcription Factor CHOP; C051684:GRP78 protein, rat; D000091342:Endoplasmic Reticulum Chaperone BiP; C008261:lead acetate