[The effects of biotin on the metabolism of ammonia and amino acids in urease-induced hyperammonemic rats].
The effects of oral and intraperitoneal administration of biotin in urease-induced hyperammonemic rats, as well as the influence of biotin deficiency, have been studied. Biotin deficiency was produced by feeding standard diet MF (Oriental Yeast Co.) supplemented with dry egg-white (egg-white group). Egg-white + biotin group had free access to 0.0014% of biotin solution at all time. Following an intraperitoneal injection of urease, 25 U/kg (B.W.), plasma ammonia levels in egg-white + biotin group were lower than in egg-white group, especially there was significance (p less than 0.05) at 8 hours after the urease injection. Similarly, plasma ammonia levels in biotin-injected rats, in which 1 mg of biotin had been injected intraperitoneally prior to the experiment, were significantly low compared with saline-injected controls at 4 and 6 hours after urease administration. Results of plasma amino acid analysis, 9 hours after the urease injection indicated that Fischer's molar ratio (Leu + Ileu + Val/Tyr + Phe) was significantly higher in the biotin-injected rats than the saline-injected control. It suggests that biotin might decrease blood ammonia by facilitating the detoxification mechanism as follow: L-glutamate + NH3----L-glutamine.
Nagamine
T
T
Saito
S
S
Yamada
S
S
Sekiguchi
T
T
Kobayashi
S
S
Nakano
M
M
D000596:Amino Acids / Q000378:metabolism*; D000641:Ammonia / Q000097:blood / Q000378:metabolism*; D000818:Animals; D001710:Biotin / Q000172:deficiency / Q000494:pharmacology*; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D014510:Urease / Q000009:adverse effects*
D000596:Amino Acids; D001710:Biotin; D000641:Ammonia; D014510:Urease