Polarization of hepatocytes is manifested by bile canalicular network formation and activation of LKB1 and AMPK, which control cellular energy metabolism. The bile acid, taurocholate, also regulates development of the canalicular network through activation of AMPK. In the present study, we used collagen sandwich hepatocyte cultures from control and liver-specific LKB1 knockout mice to examine t...

Aquaporin-8 (AQP8) water channels, which are expressed in rat hepatocyte bile canalicular membranes, are involved in water transport during bile formation. Nevertheless, there is no conclusive evidence that AQP8 mediates water secretion into the bile canaliculus. In this study, we directly evaluated whether AQP8 gene silencing by RNA interference inhibits canalicular water secretion in the huma...

Bile acid transport and secretion in hepatocytes require phosphatidylinositol (PI) 3-kinase-dependent recruitment of ATP-dependent transporters to the bile canalicular membrane and are accompanied by increased canalicular PI 3-kinase activity. We report here that the lipid products of PI 3-kinase also regulate ATP-dependent transport of taurocholate and dinitrophenyl-glutathione directly in can...

We report four unusual cases of upper eyelid retraction following periorbital trauma. Four previously healthy patients were evaluated for unilateral upper eyelid retraction following periorbital trauma. A 31-year-old man (Case 1) and a 24-year-old man (Case 2) presented with left upper eyelid retraction which developed after blow-out fractures, a 44-year-old woman (Case 3) presented with left u...

PURPOSE To analyze the features of lacrimal drainage system obstruction confirmed during external dacryocystorhinostomy surgeries and report the surgical outcomes. METHODS We reviewed the medical records of a total of 769 cases who underwent external dacryocystorhinostomy for primary lacrimal drainage obstruction between 2005 and 2014. Data about detailed location and extent of obstruction we...

Hepatic organic cation transport consists, in part, of carrier-mediated sinusoidal uptake stimulated by an inside-negative membrane potential and canalicular excretion driven by electroneutral organic cation/H+ exchange. Intracellular organic cation transport involves sequestration into acidified organelles, also mediated by organic cation/H+ exchange. A sinusoidal organic cation transporter ha...