True about prostaglandins is
|B||Present in many tissues|
|C||Some require c-AMP for their action|
|D||All are true|
Eicosanoids are formed from polyunsaturated fatty acid (eg Arachidonate)
Eg. of Eicosanoids: - Prostaglandins, thromboxanes, Leukotrienes
a. Prostaglandin →most if not all PG, are coupled by receptor to G-proteins and affect intracellular cAMP and
b. IP3 level.
c. Protective for gastric mucosa
d. Thromboxane A →synthesized by platelets and promotes vasoconstriction and platelets aggregation.
e. Prostacyclin →produced by endothelial cells and smooth muscle cells in the walls of blood vessels →it
f. inhibit platelets aggregation and, is a vasodilator.
g. Lipoxin A →dilates the microvasculature; lipoxin A and B →both inhibits the cytotoxic effect of the NK
i. Leukotrienes (B4, C4, D4) →causes Bronchoconstriction, constrict arterioles, increase vascular permeability
j. and chemoattractants for neutrophils, and eosinophils.