Fig. 5.

Protein levels of vesicle monoamine transporter type 1 (VMAT1) and chromogranin A (CgA) (both major bands, CgA1 and CgA2) in KRJ-I cells, in response to different O₂ levels. VMAT1 protein expression remained unchanged during both hypoxia and hyperoxia (A and B). In contrast, there was a significant increase in CgA1 and CgA2 protein levels after 120 min of hypoxia (C). Hyperoxia induced a small but significant increase in CgA1, whereas CgA2 did not change significantly (D). Means ± SE, n = 4–8, *P < 0.04 compared with control.