Local transport kinetics of glucose during acute and chronic nicotine infusion in rat brains.
Acute and chronic infusion of nicotine is known to result in a distinct increase in local cerebral glucose utilization (LCGU) in several brain structures. The present study addresses the question whether this increase in LCGU is paralleled by a local change in glucose transport in rat brain. Nicotine was infused either acutely for 3 hours or chronically by osmotic minipumps for one week. Local rate constants for glucose transport were measured in brain cryosections using the 3-O-[14C]methylglucose method. Local rate constants K1 and k2 were lower in part of the brain structures during acute (-10% to -20%) and in nearly all structures during chronic (-39% to -41%) nicotine. The finding of a decreased glucose transport during chronic nicotine was confirmed by additional experiments of 3-O-[14C]methylglucose transfer in an epithelial cell culture. It is concluded that acute and chronic nicotine infusion results in decreased glucose transport although LCGU is either unchanged or increased.
Duelli
R
R
Department of Physiology, University of Heidelberg, Federal Republic of Germany.
Staudt
R
R
Maurer
M H
MH
Kuschinsky
W
W
D019325:3-O-Methylglucose / Q000378:metabolism; D000818:Animals; D001692:Biological Transport / Q000502:physiology; D001921:Brain / Q000166:cytology / Q000378:metabolism*; D002460:Cell Line; D004285:Dogs; D004847:Epithelial Cells / Q000378:metabolism; D005947:Glucose / Q000378:metabolism*; D007260:Infusion Pumps; D007700:Kinetics; D008297:Male; D009538:Nicotine / Q000008:administration & dosage* / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D013997:Time Factors
D019325:3-O-Methylglucose; D009538:Nicotine; D005947:Glucose