Abstract
1. The effect of hyperinsulinaemia upon the influx of tryptophan into the brain was determined. A raised level of insulin was maintained in the circulation of rabbits for periods of up to 120 min by means of a continuous, programmed intravenous injection of the hormone, given by an electronically controlled variable-drive syringe. A similar, appropriately programmed, intravenous injection of glucose, given simultaneously with the insulin, maintained the concentration of the blood glucose within normal limits throughout each experiment, so that the results were not vitiated by the development of hypoglycaemia. 2. Raised levels of insulin in the blood affect the supply of tryptophan to the brain in two opposing ways: (a) by increasing the binding of tryptophan to the albumin in the blood, thereby reducing the level of the free tryptophan in the circulation by about a half, which would decrease the influx of tryptophan into the brain; (b) by simultaneously reducing the levels in the blood of six or more of the amino acids which compete with tryptophan for transport carriers into the brain, which would increase the influx of tryptophan. The net result of these two opposing effects is that insulin causes only a slight increase in th...Continue Reading
Citations
Jul 24, 2012·Pharmacology & Therapeutics·William A BanksMichelle A Erickson
Jul 26, 1975·Lancet·P StrattaA Vercellone
Jan 1, 1995·Cancer Chemotherapy and Pharmacology·J N RichH S Friedman
Mar 1, 1990·Journal of Neurochemistry·W M Pardridge, G Fierer
May 1, 1985·Journal of Neurochemistry·G S SarnaG Curzon
Feb 1, 1986·Journal of Neurochemistry·P Brust
Nov 1, 1982·Journal of Neurochemistry·G S SarnaG Curzon
Dec 3, 1992·Nature·K R BhaskarJ T LaMont
Feb 1, 1986·Digestive Diseases and Sciences·R S WeinsteinB U Pauli
Apr 14, 2020·Cell Proliferation·Xiao Han ZouRan Ji Cui
Feb 23, 2020·The British Journal of Nutrition·Yan LiDongfeng Zhang
Jul 15, 2015·Review of General Psychology : Journal of Division 1, of the American Psychological Association·Rafael Wlodarski, Robin I M Dunbar
Jul 11, 2012·Endocrinology·William A Banks
Jun 19, 2018·Molecular Psychiatry·Marion SotoC Ronald Kahn
May 28, 2019·Nature Reviews. Endocrinology·William A Banks
Nov 27, 2015·Metabolic Brain Disease·Eder GambetaJanaina Menezes Zanoveli
Jan 1, 1987·Acta Medica Scandinavica. Supplementum·A D ThomsonG K Shaw
Nov 1, 1982·Pharmacology, Biochemistry, and Behavior·J A FinkelsteinJ E Fischer
Jun 3, 2021·Journal of Personalized Medicine·Lina Begdache, Cara M Patrissy