False statement about bilirubin is
Bilirubin transpo: Bilirubin circulates in plasma noncovalently, bound to albumin. It is taken up across the sinusoidal membrane of hepatocytes by a carrier-mediated mechanism. Bilirubin uptake is mediated by a liver-specific sinusoidal organic anion transpo protein, (OATP1B1, SLC21A6) Then bilirubin is directed by cytosolic binding proteins (e.g., glutathione S-transferase B, fatty acid binding protein) to the ER. It is conjugated with uridine diphosphate (UDP)-glucuronic acid by the enzyme bilirubin UDP-glucuronyl transferase (B-UGT). Conjugated bilirubin is directed toward the canalicular membrane, and it is transpoed into the bile canaliculus by an adenosine triphosphate (ATP)-dependent pump. The responsible protein is multidrug resistance-associated protein-2 (MRP2, ABCC2) Small amounts of bilirubin glucuronides are secreted across the sinusoidal membrane MRP3 (ABCC3) Conjugated bilirubin in plasma undergoes renal elimination Ref: Sleisenger and Fordtran's, E-9, P-324
Bilirubin circulating in plasma by covalently binding with albumin
Bilirubin is taken up across the sinusoidal (basolateral) membrane of hepatocytes by a carrier-mediated mechanism
Conjugated bilirubin in plasma undergoes stool elimination
Conjugated bilirubin is then directed primarily toward the canalicular (apical) membrane