Metabolic Effects of Intraoperative Amino Acid Infusion in Mongrel Dogs

Abstract

Background: Intraoperative amino acid infusion can attenuate the decrease in core temperature, but the metabolic effects are uncertain. Methods: Thirty-six healthy mongrel dogs undergoing ileectomy under general anesthesia were infused intraoperatively with normal saline or 18 compound amino acids at 6, 12, and 24 kJ·kg^–1·h^–1 (NS, 6-, 12-, and 24-kJ groups) and studied until 24 h after the operation. Blood glucose, plasma insulin, free fatty acids, and triglyceride concentrations were determined at 7 defined time points. Muscle aminograms, urinary urea, and 3-methylhistidine excretions were measured before and after the operation. Results: Blood glucose and plasma insulin increased amino acid dose dependently during the operation and in the early period after the operation. Free fatty acids were significantly lower in the 12- and 24-kJ groups compared with the NS group at the end of the operation. The negative nitrogen balance was alleviated dose dependently in the amino acid groups on operation day. The urinary 3-methylhistidine decreased significantly during the first 24 h after the operation in the 24-kJ group, while it increased in the other groups with the largest increase in the NS group. Basic, branched-chain, and aromatic amino acids in the vastus lateralis muscle increased dose dependently at the end of the operation in the amino acid groups. Conclusion: Intraoperative amino acid infusion has the dose-dependent effects of increasing blood glucose, inhibiting fat mobilization and muscle protein breakdown.

Leucine and Protein Metabolism in Obese Zucker Rats

“…Hyperaminoacidemia and elevated plasma Leu have been linked to increased mTOR activity [10], [22], [23] and PKC pathway activation [71], [72]. These pathways have been linked to activation of protein synthesis consistent with our observations in obese rats.…”

“…[22]. In contradistinction, hyperaminoacidemia in obese Zucker rats was associated with an increase in both protein synthesis and degradation.…”

“…However this too has not always been observed [20], [21] and seems inconsistent with the findings that aminoacidemia in lean animals and in obesity activates mTOR kinase activity. In lean animals, such signaling by BCAAs increases protein synthesis and inhibits muscle protein degradation as measured by changes in 3-methylhistidine (3-MeHis) [10], [22], [23]. However skeletal muscle mass is reduced in obese Zucker rats consistent with increased 3-MeHis [24], [25], [26].…”

Inadvertent Perianesthetic Hypothermia in Small Animal Patients

“…Although this technique is not yet recommended for use in a veterinary clinical setting, studies in humans and dogs have demonstrated safety and effectiveness. 51,52 COMPLICATIONS Complications associated with using techniques to reduce the severity of IPH are usually associated with the specific technique. Patient skin burns are one of the more severe complications and have been associated with heat lamps or defective or inappropriately operated active technique equipment.…”

Intravenous infusion of amino acids in dogs attenuates hypothermia during anaesthesia and stimulates insulin secretion

“…The metabolic and thermogenic effects of intraoperative amino acid infusion have also been studied in dogs (Jin et al. ; Clark‐Price et al. ).…”