protein kinase
C beta
Nuclear factor
NF-kappa-B p105
subunit
Gq protein
signaling
cascade
Phospholipase C
Inositol 1,4,5-
trisphosphate
receptor type 1
Protein kinase
C alpha type
Voltage-
dependent
P/Q-type
calcium channel
subunit
alpha-1A
Voltage-
dependent
L-type calcium
channel subunit
beta-1
Voltage-
dependent
calcium channel
subunit
alpha-2/delta-2
Histamine H1
receptor
Inositol 1,4,5-trisphosphate
Histamine
Doxylamine
Ca+
Ca+
Doxylamine
Phosphatidylinositol
4,5-bisphosphate
Calcium
↑ Mediator Release
Diacylglycerol
↑ Pro-inflammatory
Cytokines, Cell Adhesion
Molecules, Chemotactic
Factors
Mast Cells
Release
Histamine
Ca+
Calcium
Nucleus
↑ Antigen Presentation
↓ Mast Cell Stabilization
Endoplamic Reticulum
There is an overall decrease
in calcium levels in the
cytosol caused by the
inhibition of the Gq
signaling cascade
Cytosol
T Cell
Clemastine antagonizes
Histamine H1 receptors in
endothelial cells,
preventing histamine from
activating the receptor
T Cell