| Literature DB >> 15009676 |
Isabel Roncero1, Elvira Alvarez, Julie A Chowen, Carmen Sanz, Alberto Rábano, Patricia Vázquez, Enrique Blázquez.
Abstract
The glucose transporter isoform-2 (GLUT-2) and glucokinase are considered to be components of a glucose sensor system controlling several key processes, and hence may modulate feeding behaviour. We have found GLUT-2 and glucokinase mRNAs in several brain regions, including the ventromedial and arcuate nuclei of the hypothalamus. GLUT-2, glucokinase and glucokinase regulatory protein mRNAs and proteins were present in these areas as determined by biochemical approaches. In addition, glucose-phosphorylating activity with a high apparent Km for glucose that displayed no product inhibition by glucose-6-phosphate was observed. Increased glycaemia after meals may be recognized by specific hypothalamic neurones due to the high Km of GLUT-2 and glucokinase. This enzyme is considered to be the true glucose sensor because it catalyses the rate-limiting step of glucose catabolism its activity being regulated by interaction with glucokinase regulatory protein, that functions as a metabolic sensor.Entities:
Mesh:
Substances:
Year: 2004 PMID: 15009676 DOI: 10.1046/j.1471-4159.2003.02269.x
Source DB: PubMed Journal: J Neurochem ISSN: 0022-3042 Impact factor: 5.372