Journal:
Article Title: Hypoxia-induced mitogenic factor/FIZZ1 induces intracellular calcium release through the PLC-IP 3 pathway
doi: 10.1152/ajplung.90416.2008
Figure Lengend Snippet: Effects of 2-aminoethoxydiphenyl borate (2-APB) and ryanodine on HIMF-induced intracellular Ca2+ release and induction of intracellular inositol 1,4,5-trisphosphate (IP3). Fluo 4-loaded human pulmonary artery SMC were pretreated with 50 μmol/l 2-APB (IP3 receptor antagonist) or 100 μmol/l ryanodine (ryanodine receptor antagonist) for 30 min at room temperature and maintained in Ca2+-free buffer at the time of HIMF stimulation. Complete blockade of [Ca2+]i response to HIMF by 2-APB (A), but not by ryanodine (B), indicates that HIMF initiates Ca2+ release via IP3 receptors. Although ryanodine did not prevent HIMF-induced Ca2+ release, it did reduce the resulting fluorescence intensity (P < 0.05), suggesting that Ca2+ release via ryanodine receptor might also be attributable to HIMF-induced increases in [Ca2+]i. Values are means ± SE of 3 independent experiments. C: IP3 levels in human pulmonary artery SMC were determined by Amersham IP3 assay kit at 0, 30, 60, 90, 120, and 300 s after HIMF stimulation. HIMF induced a rapid IP3 increase that peaked at 60 s (P < 0.05) and returned to baseline after 120 s. Values are means ± SE of 3 independent determinations.
Article Snippet: Primary human pulmonary artery SMC (Cambrex Biosciences, Walkersville, MD) were maintained in the growth medium SGM-2 (Cambrex Biosciences) containing 5% FCS, 0.5 ng/ml human epithelial growth factor, 2 ng/ml human fibroblast growth factor, and 5 μg/ml insulin under 5% CO 2 -21% O 2 in a humidified incubator at 37°C.
Techniques: Fluorescence