You started a patient on oral warfarin. Which of the following factors show the most rapid decline in the blood levels after the initiation of warfarin therapy?
Protein C, protein S (both having anticoagulant property) and osteocalcin contain glutamate residues that require Vit. K dependent γ carboxylation. These are also inhibited by oral anticoagulants, but density of adult bone is not affected, though new bone formation may be depressed.
Reference: Essentials of Medical Pharmacology Seventh Edition KD TRIPATHI  page no 621
Factor VII
Protein C
Factor X
Prothrombin