Feeding and arginine deficient diets differentially alter free amino acid concentrations of hindlimb muscle in young rats

Abstract

Summary. The objective of these experiments was to examine short-and long-term (7 d) effects of arginine-deficient diets on free amino acid concentrations in hindlimb muscle of rats. In rats fed the control diet containing arginine (+Arg), muscle alanine and methionine concentrations were higher 1 and 2h after feeding compared to food-deprived rats, whereas branchedchain amino acids, arginine and asparagine concentrations were lower postprandially. In Experiment 1, rats were fed an arginine-deficient (-Arg) diet with glutamate (+Glu) substituted for arginine; alanine (+Ala), ornithine (+ Orn) or citrulline (+ Cit) were substituted for arginine in Experiment 2. In Experiment 1, arginine concentrations decreased in blood but not in muscle. This contrasts with rats fed -Arg/+ Ala or -Arg/+ Orn diets which had muscle arginine concentrations less than half the concentrations in controls or in rats fed the -Arg/+Cit diet. Muscle essential amino acids in Experiment 2 did not differ by diet, but muscle branched-chain amino acids were elevated relative to controls in the rats fed -Arg/+Ala or -Arg/+Orn diets; however, rats fed the -Arg/+ Cit diet had levels similar to the controls. Also, muscle branched-chain amino acids were correlated with glutamine concentrations in both blood and muscle. The measurements in the post-meal period suggest that muscle amino acid concentrations may more closely reflect dietary amino acid patterns than do blood amino concentrations.

Effects of low‐protein diet and feed restriction on mRNA expression of cationic amino acid transporters in porcine skeletal muscles

“…Here, both the LP and FR diets affected mostly lysine and arginine concentrations in the skeletal muscle rather than in plasma. Therefore, compared to blood, AA concentrations in the skeletal muscle may more closely reflect dietary AA status, which is consistent with previous findings (Hartman & Prior, 1997).…”

Effects of low-protein diet and feed restriction on mRNA expression of cationic amino acid transporters in porcine skeletal muscles

“…Here, both the LP and FR diets affected mostly lysine and arginine concentrations in the skeletal muscle rather than in plasma. Therefore, compared to blood, AA concentrations in the skeletal muscle may more closely re ect dietary AA status, which is consistent with previous ndings (Hartman and Prior 1997).…”

Effect of Amniotic Injection of N-Carbamylglutamate on Meat Quality of Broilers

“…The method of determining free amino acids was improved based on the foundation of Hartman et al [23] Briefly, the sample (frozen muscle, 0.5 g) was placed into a saline solution (ice-cold, 4.5 mL, 0.8%) to homogenize. After centrifugation (4 • C, 9000× g, 10 min), 300 µL supernatant was mixed with 300 µL 1.5 M perchloric acid, left to stand for 10 min, then mixed with 150 µL of a 2 M potassium carbonate solution and left to stand for 20 min.…”