![]() |
|
|
Department of Animal Science and Faculty of Nutrition, Texas A&M University, College Station, TX 77843-2471 * Research Diets Inc., New Brunswick, NJ 08901-3275
This study was designed to quantify the effect of dietary manganese deficiency on rat hepatic Mn concentration and arginase activity. Weanling male Sprague-Dawley rats were randomly assigned to two groups of nine rats each and fed L-amino acid diets with 0 or 48 µg Mn/g diet for 21 d. After 21 d, hepatic Mn concentration (µmol/g liver dry wt, mean ± SEM) was 0.130 ± 0.005 for the control group but was lower (P < 0.01) in the Mn-deficient group (0.040 ± 0.003). There were no differences in the hepatic concentrations of any other measured mineral. Hepatic arginase activity [mmol ornithine/(g hepatic protein·min)] was 1.55 ± 0.22 in the control group and was lower (P < 0.01) in the Mn-deficient group (1.12 ± 0.26). Plasma ammonia concentration was 301 ± 6 µmol/L in the control group and was higher (P < 0.01) in the Mn-deficient group (480 ± 8 µmol/L). In contrast, plasma urea concentration was higher (P < 0.01) in the control group (350 ± 10 µmol/L) than in the Mn-deficient group (267 ± 7 µmol/L). There were no differences in plasma concentrations of arginine or other amino acids between the control and the Mn-deficient groups. Our results demonstrate for the first time that dietary Mn deficiency results in altered plasma concentrations of ammonia and urea in association with decreased hepatic Mn concentration and arginase activity in young growing rats.
KEY WORDS: manganese arginase ammonia urea cycle rats
1 Supported by teaching funds from Texas A&M University, a Hatch project #8200 from the Texas Agricultural Experiment Station (to G. Wu), and donations from Research Diets, Inc. (New Brunswick, NJ).
2 The costs of publication of this article were defrayed in part by the payment of page charges. This article must therefore be hereby marked "advertisement" in accordance with 18 USC section 1734 solely to indicate this fact.
3 To whom correspondence should be addressed
Manuscript received 5 August 1993. Revision accepted 27 October 1993.
This article has been cited by other articles:
![]() |
A. Z. Kalea, D. A. Schuschke, P. D. Harris, and D. J. Klimis-Zacas Cyclo-Oxygenase Inhibition Restores the Attenuated Vasodilation in Manganese-Deficient Rat Aorta J. Nutr., September 1, 2006; 136(9): 2302 - 2307. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. Sabbatini, A. Pisani, F. Uccello, G. Fuiano, R. Alfieri, A. Cesaro, B. Cianciaruso, and V. E. Andreucci Arginase inhibition slows the progression of renal failure in rats with renal ablation Am J Physiol Renal Physiol, April 1, 2003; 284(4): F680 - F687. [Abstract] [Full Text] [PDF] |
||||