Increased permeability in acute inflammation is due to-

Ans. (a) Histamine(Ref: Robbins 9th/pg 74; 8th/pg 47)Increased vascular permeabilityFormation of endothelial gaps (Immediate transient response) is the most common mechanism Q for increased permeability.Most important immediate mediator responsible for Immediate transient response Q is histamine QOther immediate mediators: bradykinin, leukotriene, substance PSomewhat delayed mediators: TNF,IL-1,lFN-gOption b: IL2: IL-2 is known to activate T-cells, especially CD4+ T-helper cells. Other minor function of IL2 are: IL2 can activate lipoxygenase pathway with release of lipoxygenase metabolites which play a role in pulmonary vascular permeability. (Cytokines and Inflammation By Edward S. Kimball, pg215)Option c and d: are mediators of chronic inflammation Here the answer is definitely histamine [?]IL2