Figure 2.

Lactisole increases ER Ca²⁺ content and size. (a) The 20 mM lactisole 1 h pretreatment increases peak Ca²⁺ release by 275% and ER Ca²⁺ content by 200%. (b) Analyzing the initial linear slope from trace in experiment (a), as highlighted by red circle and enlarged in graph on the right, revealed that lactisole treatment (20 mM, 1 h) caused a 300% steeper slope relative to untreated cells. (c) Beas-2B cells treated with 20 mM lactisole for 1 h revealed a decrease in ER tracker fluorescence. (d) Beas-2Bs expressing ER Ca²⁺ sensor D1ER show that denatonium treatment reduced ER Ca²⁺ stores 250% with 20 mM lactisole pretreatment (1 h). (e) Lactisole increases denatonium-induced Ca²⁺ release regardless of extracellular Ca²⁺ (f) Both 10 and 20 mM lactisole pretreatment (1 h) increases histamine-induced Ca²⁺ release by 50%. Traces are representative of ≥3 experiments. Bar graphs containing two comparisons were analyzed via t-test; bar graphs containing >2 comparisons were analyzed via ANOVA using Bonferroni’s post-test for multiple comparisons * p < 0.05, ** p < 0.01, *** p < 0.001.