Abstract
Exogenous tyrosine lowers blood pressure in spontaneously hypertensive rats (SHR). The artificial sweetener aspartame also elevates blood and brain tyrosine levels in rats by being hydrolyzed to phenylalanine, which is then rapidly hydroxylated to tyrosine in the liver. Hence we tested the ability of aspartame; its hydrolytic products phenylalanine, aspartic acid and methanol; and of tyrosine itself to lower blood pressure in SHR. For one week prior to experimentation rats were acclimated to the indirect blood pressure measurement technique; on the day of an experiment they received I.P. injections (mg/kg) of aspartame (12.5-200), tyrosine (25-200) or phenylalanine (100-200), or of aspartic acid or methanol in the doses theoretically contained within 200 mg/kg aspartame. Animals receiving 50, 100 or 200 mg/kg of aspartame exhibited maximum falls in blood pressure of 17.3, 24.2 and 19.3 mmHg, respectively. All changes were significant, as determined by ANOVA and the Newman-Keuls test (p less than 0.05). Tyrosine or phenylalanine also lowered blood pressure, but aspartic acid or methanol produced no significant effects. Co-administration of aspartame with valine, a large neutral amino acid that competes with phenylalanine or tyro...Continue Reading
References
Jan 1, 1978·Annual Review of Pharmacology and Toxicology·A J Mandell
Apr 3, 1978·Life Sciences·N WeinerE Barnes
Aug 1, 1975·Proceedings of the National Academy of Sciences of the United States of America·W LovenbergI Hanbauer
Jul 1, 1979·Proceedings of the National Academy of Sciences of the United States of America·A F SvedR J Wurtman
Jan 1, 1976·Life Sciences·J A Zivin, J J Bartko
Mar 30, 1986·Toxicology and Applied Pharmacology·R A Coulombe, R P Sharma
Nov 9, 1985·Lancet·R J Wurtman
Apr 30, 1985·Biochemical and Biophysical Research Communications·D Grobelny, R E Galardy
Mar 1, 1986·The Journal of Nutrition·H Yokogoshi, R J Wurtman
Apr 28, 1983·Nature·S El MestikawyM Hamon
Jul 1, 1984·The American Journal of Clinical Nutrition·H YokogoshiR J Wurtman
May 1, 1984·The American Journal of Clinical Nutrition·T J MaherR J Wurtman
Oct 1, 1983·Journal of Neurochemistry·B S GlaeserR J Wurtman
Apr 4, 1983·Life Sciences·J D FernstromM A Gillis
Aug 18, 1983·The New England Journal of Medicine·R J Wurtman
Oct 1, 1982·Journal of Neurochemistry·M C AragónF Valdivieso
May 1, 1981·Science·L A ConlayR J Wurtman
Oct 1, 1996·Human Gene Therapy
Citations
Jan 1, 1987·Journal of Neural Transmission·R J Wurtman, T J Maher
Jan 31, 1989·European Journal of Pharmacology·D L Yourick, R E Tessel
May 1, 1990·Pharmacology & Toxicology·S Ekholm, H Karppanen
Nov 3, 2007·Neuropharmacology·Brian P BergstromTricia A Skaggs
Nov 14, 1997·Pharmacology & Toxicology·N Hutri-KähönenM Kähönen
Nov 16, 2010·The Journal of Urology·Amy E KrambeckJohn C Lieske
Jul 1, 1995·The Journal of Urology·C WeberR Rettig
Sep 1, 1995·The Journal of Urology·M GuptaM L Stoller
Dec 30, 2011·The American Journal of Clinical Nutrition·Maria MaerskBjørn Richelsen
Jun 1, 1994·Hypertension·W Auch-SchwelkE Fleck
Sep 18, 2015·Neural Computation·Takashi Takenouchi
Oct 30, 2001·British Journal of Pharmacology·N HosogaiT Goto