Thrombopotein is considered to be the primary growth factor for regulating rnegakaryopoiesis and thrombopoiesis. It do its action t1routhbinding to its receptor (Thvombopotei n receptor)present in platelets megakaryocytes. The predominant site of TPO production is liver and to lesser density the kidneys. Reticulated platelets is the most recentplatelets released in the circulation. with advancement of liver disease platelets increase.