MCQ IN MEDICINE

Detailed explanation-1: -VEGF-A and its receptors, VEGFR-1 and VEGFR-2, play a major role in vasculogenesis and angiogenesis. In addition, sFlt-1, a soluble form of VEGFR-1, is expressed in various cells such as trophoblasts and negatively regulates angiogenesis.

Detailed explanation-2: -The basic steps of sprouting angiogenesis include enzymatic degradation of capillary basement membrane, endothelial cell (EC) proliferation, directed migration of ECs, tubulogenesis (EC tube formation), vessel fusion, vessel pruning, and pericyte stabilization.

Detailed explanation-3: -Angiogenesis is responsible for the remodeling and expansion of this network. While vasculogenesis refers to in situ differentiation and growth of blood vessels from mesodermal derived hemangioblasts, angiogenesis comprises two different mechanisms: endothelial sprouting and intussusceptive microvascular growth (IMG).

Detailed explanation-4: -The VEGF signaling pathway Upstream activators stimulate the production of VEGF. VEGF binds to receptors on endothelial cells. Angiogenesis is mediated primarily through the interaction of VEGF-A with VEGFR-2. Other variants of the VEGF ligand and receptor play a secondary role in this process.