Increased neural activity in transgenic mice with brain IGF-I overexpression: a [3H]2DG study.
To evaluate whether insulin-like growth factor-I (IGF-I) modulates neural activity in vivo, relative levels of brain [3H]2-deoxyglucose (2DG) uptake were compared in adult behaving and anesthetized wild type (wt) mice, and transgenic (Tg) mice with either brain IGF-I overexpression or ectopic brain expression of IGF binding protein-1 (IGFBP-1). Overall, awake behaving IGF-I Tg mice showed significant increases in brain 2DG uptake compared with wt and IGFBP-1 Tg mice. These differences were eliminated after anesthesia. 2DG uptake was similar in awake behaving, and anesthetized wt and IGFBP-1 Tg mice. Our observations thus suggest that IGF-I increases neural activity levels in vivo, and that it is not involved in regulating glucose consumption in the adult brain.
Gutiérrez-Ospina
G
G
Department of Pediatrics, University of North Carolina at Chapel Hill, 27599-7220, USA.
Saum
L
L
Calikoglu
A S
AS
Díaz-Cintra
S
S
Barrios
F A
FA
D'Ercole
A J
AJ
D000818:Animals; D001921:Brain / Q000254:growth & development / Q000378:metabolism*; D003847:Deoxyglucose / Q000378:metabolism*; D018970:Insulin-Like Growth Factor Binding Protein 1 / Q000378:metabolism; D007334:Insulin-Like Growth Factor I / Q000096:biosynthesis*; D008297:Male; D051379:Mice; D008822:Mice, Transgenic; D009419:Nerve Tissue Proteins / Q000378:metabolism; D011869:Radioligand Assay; D009435:Synaptic Transmission / Q000502:physiology*; D014316:Tritium
D018970:Insulin-Like Growth Factor Binding Protein 1; D009419:Nerve Tissue Proteins; D014316:Tritium; D007334:Insulin-Like Growth Factor I; D003847:Deoxyglucose