Following MI, staining of cardiac tissue with TTC within 12 hours of infarction showed red color. This red colour is seen:

Ans: b (In the non infracted.....) Ref: Direct pick from Robbins, 7th ed, p. 578-79Myocardial infarcts 2-3 hours after infarct can be stained by immersion of tissue slices in a solution - Triphenyl tetrazolium chloride (TTC). This histochemical stain imparts a brick red colour to the intact, non infarcted myocardium where the dehydrogenase enzymes are preserved.But the dehydrogenase enzymes are depleted in the area of ischaemic necrosis (they leak out through the damaged cell membrane).So the infarcted area is revealed as an unstained pale zone.