And....



A decrease in glucose production is associated with an increase in plasma citrulline response to oral arginine in normal volunteers.

Apostol AT, et al. Show all

Metabolism. 2003 Nov;52(11):1512-6.

Department of Internal Medicine, Harbor-UCLA Medical Center, David Geffen School of Medicine at UCLA, Torrance, CA 90509, USA.

Abstract Acute arginine administration (30 g) increases insulin secretion and reduces glucose production (GP). A slower administration of L-arginine may have direct effect on the liver without increasing C-peptide or insulin secretion. We tested the direct effect of oral L-arginine on fasting GP in 15 normal-weight volunteers and compared these to a group of L-alanine-treated controls (placebo). Volunteers were admitted to the General Clinical Research Center for a 3-day stay. Three grams of freebase arginine or alanine was ingested hourly between 4 am and 2 pm. Neither arginine nor alanine had an effect on C-peptide or insulin concentration. Oral arginine, but not alanine, increased plasma arginine, citrulline, and ornithine concentrations. Arginine-treated volunteers had a greater fall in GP as compared to the alanine-treated group (16.2% +/- 1.9% v 9.7% +/- 3.6%, respectively; P<.05). Five volunteers treated with arginine had less than a 30% increase in citrulline concentration (26 +/-2 to 32 +/- 2 micromol/L, mean +/- SEM) and 10 volunteers had equal to or greater than a 30% increase in plasma citrulline concentration (29 +/- 2 to 49 +/- 4 micromol/L, P<.05). Since citrulline is generated in the conversion of arginine to nitric oxide (NO), the failure of oral arginine to increase citrulline concentration suggests that NO generation may be varied in different individuals. The increased plasma citrulline group reduced GP by 18.2% +/- 1.9% over the final 4 hours of arginine administration (2.00 +/- 0.08 to 1.64 +/- 0.07 mg/kg/min; P<.01). In contrast, GP only decreased by 12.4% +/- 3.9% (1.97 +/- 0.13 to 1.73 +/- 0.13 mg/kg/min; not significant [NS]) in those who had little to no increase in plasma citrulline concentration. The 12% decrease in GP in the hyporesponders was similar to the 10% decrease seen in the alanine-treated normal volunteers (9.7% +/- 3.6%). Individuals may have a variable NO response from an oral arginine administration. GP is suppressed in those who have a greater increase in plasma citrulline concentration.

PMID 14624416 [PubMed - indexed for MEDLINE]

Originally Posted by Right Hook

Are you sure? I haven't gone over the arginine /insulin response in years but a quick search showed...



Oral arginine does not stimulate an increase in insulin concentration but delays glucose disposal.

Gannon MC, et al. Show all

Am J Clin Nutr. 2002 Nov;76(5):1016-22.

Metabolic Research Laboratory and the Section of Endocrinology, Metabolism, and Nutrition, Minneapolis Veterans Administration Medical Center, Department of Food Science and Nutrition, University of Minnesota, Minneapolis 55417, USA. ganno004@tc.umn.edu

Abstract BACKGROUND: Ingested protein increases circulating insulin concentrations. Several years ago it was also determined that an intravenously administered mixture of 10 essential amino acids stimulated insulin secretion. Of these, arginine was the most potent. The effect was synergistic with administered glucose.

OBJECTIVE: Because the amounts of amino acid administered intravenously were very large and because ingested arginine is partially metabolized in the intestinal mucosa, we were interested in determining whether orally administered arginine stimulates a rise in circulating insulin concentration and whether arginine affects the glucose-induced rise in insulin concentration.

DESIGN: Nine healthy subjects (4 women and 5 men aged 21-52 y) ingested 1 mmol arginine/kg lean body mass, 1 mmol arginine/kg lean body mass + 25 g glucose, 25 g glucose alone, and water only, in random order on separate occasions, at 0800. Blood samples were obtained at baseline and at 10-min intervals over the next 2 h and were assayed for glucose, insulin, glucagon, and amino acid concentrations. The half-time for gastric emptying was determined by scintigraphy.

RESULTS: Unlike with intravenous administration, ingested arginine did not stimulate a rise in insulin concentration. The glucagon concentration was increased. Arginine attenuated and prolonged the glucose rise when it was ingested with glucose. Gastric emptying time was similar after ingestion of glucose alone or arginine plus glucose.

CONCLUSION: Arginine, in an amount likely to be ingested in a high-protein meal, does not stimulate insulin secretion but attenuates the increase in glucose when given with glucose.

ok, scratch what i said then