Fig. 5.

Histamine stimulation of BMSCs regulates IL-6 production via the MAP Kinase Pathway

(A) We measured cytosolic Ca²⁺ concentrations with Fura2 in individual cells. Addition of histamine (10⁻⁵ M) evoked a rapid increase in cytosolic Ca²⁺ peaking at 30 seconds after stimulation, followed by a sustained elevation.

(B) IL-6 increase in the presence of specific PLC inhibitor

(C) Western blot analysis shows the presence of p38, ERK and JNK. Addition of histamine elicited the activation of p38, ERK, and JNK after 15 minutes and declined to basal level by 60 minutes.

(D) IL-6 increase in the presence of specific MAP kinase inhibitors. SB203580, a specific p38 inhibitor, PD98059, a specific ERK inhibitor and SP600125, a specific JNK inhibitor all significantly impaired histamine's ability to induce BMSCs IL-6 production.