Pentobarbital inhibits glucose uptake, but not water transport by glucose transporter type 3.
To understand the mechanisms underlying the neuroprotective efficacy of barbiturates, the effect of pentobarbital on glucose uptake and water transport was determined in Xenopus oocytes expressing glucose transporter type 3 (GLUT3). Pentobarbital induced a 50% concentration-dependent inhibition in glucose uptake, but exerted no effect on water transport by GLUT3. Eadie-Hofstee analysis showed that pentobarbital decreased Vmax significantly, but not Km of GLUT3 for 2-deoxy-D-glucose. Although the protein kinase C (PKC) activator significantly decreased glucose uptake by GLUT3, no additive or synergistic interactions were observed between the PKC activator and pentobarbital. Our results suggest that pentobarbital may play an important role in neuroprotection by inhibition of glucose uptake by GLUT3 by a mechanism involving PKC.
Department of Dental Anesthesiology, Institute of Health Biosciences, The University of Tokushima Graduate School, Tokushima, Japan. tomioka@dent.tokushima-u.ac.jp
Shigemasa
S
Tomioka
Miyuki
M
Kaneko
Nobuyoshi
N
Nakajo
D000818:Animals; D001692:Biological Transport / Q000187:drug effects; D018757:GABA Modulators / Q000494:pharmacology*; D005947:Glucose / Q000378:metabolism*; D051274:Glucose Transporter Type 3 / Q000187:drug effects* / Q000378:metabolism; D018696:Neuroprotective Agents / Q000494:pharmacology*; D009865:Oocytes / Q000187:drug effects / Q000378:metabolism; D010424:Pentobarbital / Q000494:pharmacology*; D011493:Protein Kinase C / Q000378:metabolism*; D014867:Water / Q000378:metabolism; D014982:Xenopus laevis
D018757:GABA Modulators; D051274:Glucose Transporter Type 3; D018696:Neuroprotective Agents; D014867:Water; D011493:Protein Kinase C; D010424:Pentobarbital; D005947:Glucose