Discrete brain areas express the insulin-responsive glucose transporter GLUT4.
Whether or not glucose utilization in the brain is insulin-dependent is still a controversial issue. We looked for the presence of the insulin-sensitive glucose transporter (GLUT4) in rat brain and obtained the following results: (1) poly(A) RNAs from the hypothalamus and anterior medulla oblongata hybridize with a cDNA probe for GLUT4; (2) reverse transcription-polymerase chain reaction (RT-PCR) on RNA from various brain nuclei detects GLUT4 transcripts; (3) immunocytochemistry, using a polyclonal antibody to GLUT4; reveals a specific immunostaining pattern, whereas both electronic microscopy and double immunofluorescence staining, using a neurofilament protein marker, indicate a neuronal localization. These results are discussed in terms of a putative neuromodulator role of insulin, via glucose utilization, in brain areas involved in the regulation of fuel metabolism.
Leloup
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C
Laboratoire de Physiopathologie de la Nutrition, CNRS, Paris, France.
Arluison
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M
Kassis
N
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Lepetit
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N
Cartier
N
N
Ferré
P
P
Pénicaud
L
L
D000595:Amino Acid Sequence; D000818:Animals; D015152:Blotting, Northern; D001923:Brain Chemistry / Q000502:physiology*; D005260:Female; D051275:Glucose Transporter Type 4; D007150:Immunohistochemistry; D007328:Insulin / Q000502:physiology*; D008969:Molecular Sequence Data; D009004:Monosaccharide Transport Proteins / Q000032:analysis* / Q000235:genetics; D009124:Muscle Proteins; D009419:Nerve Tissue Proteins / Q000032:analysis* / Q000235:genetics; D016133:Polymerase Chain Reaction / Q000379:methods; D012333:RNA, Messenger / Q000032:analysis*; D051381:Rats; D017208:Rats, Wistar; D014158:Transcription, Genetic
D051275:Glucose Transporter Type 4; D007328:Insulin; D009004:Monosaccharide Transport Proteins; D009124:Muscle Proteins; D009419:Nerve Tissue Proteins; D012333:RNA, Messenger; C495694:Slc2a4 protein, rat