Fibroblast growth factor 2 stimulates noggin via the ERK mitogen-activated protein kinase and NF-κB pathways. Nucleus pulposus cells isolated from bovine intervertebral disc were cultured in a monolayer in 12-well plates at 8 × 105 cells/cm2, and were serum-starved by changing the media to serum-free DMEM/F-12 with antibiotics for 24 hours before treatment. (a) Cells were then treated with 0.1 to 10 ng/ml fibroblast growth factor 2 (FGF2) and 1 ng/ml IL-1β. (b) Serum-starved cells were treated with 10 ng/ml FGF2 in the presence or absence of the chemical inhibitors of ERK (ERKi, 25 μM) or IKK (IKKi, 25 μM). The cells were collected after 24 hours, and total RNA was extracted to perform real-time RT-PCR of the noggin gene. Error bars represent three different donors in three separate experiments.