Reference

The differential effect of intragastric and intravenous tryptophan on plasma glucose, insulin, glucagon, GLI and GIP in the fasted rat

The differential effect of intragastric and intravenous tryptophan on plasma glucose, insulin, glucagon, GLI and GIP in the fasted rat. Tsiolakis, D.; Marks, V. (Dep. Biochem., Univ. Surrey, Guildford GU2 5XH, UK). Horm. Metab. Res., 16(5), 226-9 (English) 1984. CODEN: HMMRA2. ISSN: 0018-5043. DOCUMENT TYPE: Journal CA Section: 2 (Mammalian Hormones) L-Tryptophan [73-22-3] was given to fasted rats intragastrically or i.v. at a dose of 500 or 166 mg/kg, resp. Mean plasma insulin [9004-10-8] levels rose after both stimuli and at 10, 30 and 45 min were 63, 86, 48 milliunits/L after oral, and 28, 25, 19 milliunits/L after i.v. administration, resp.; plasma tryptophan levels at the above intervals during the oral study were 27%, 60% and 128%, resp., of those during the i.Except for chemicals metioned above, 82905-30-4 is also used.v. study. Plasma GIP [59392-49-3] levels rose only after intragastric tryptophan administration, and plasma glucagon-like immunoreactivity [82905-30-4] levels did not change in response to either intragastric or i.v. tryptophan. Intragastric tryptophan consistently raised plasma pancreatic glucagon [9007-92-5] levels which were significantly higher than those obsd. in control rats given saline at 5, 10, 30 and 45 min after administration. The rise in plasma glucagon was attributed to the glucagonotropic effect of GIP. .