Evidence that L-glutamine is better than L-alanine as gluconeogenic substrate in perfused liver of weaned fasted rats submitted to short-term insulin-induced hypoglycaemia.
Gluconeogenesis in livers from overnight fasted weaned rats submitted to short-term insulin-induced hypoglycaemia (IIH) was investigated. For this purpose, a condition of hyperinsulinemia/hypoglycaemia was obtained with an intraperitoneal (ip) injection of regular insulin (1.0 U kg(-1)). Control group (COG group) received ip saline. The studies were performed 30 min after insulin (IIH group) or saline (COG group) injection. The livers from IIH and COG rats were perfused with L-alanine (5 mM), L-lactate (2 mM), L-glutamine (10 mM) or glycerol (2 mM). Hepatic glucose, L-lactate and pyruvate production from L-alanine was not affected by IIH. In agreement with this result, the hepatic ability in producing glucose from L-lactate or glycerol remained unchanged (IIH group vs. COG group). However, livers from IIH rats showed higher glucose production from L-glutamine than livers from COG rats and, in the IIH rats, the production of glucose from L-glutamine was higher than that from L-alanine. The higher glucose production in livers from the IIH group, when compared with the COG group was due to its entrance further on gluconeogenic pathway. Taken together, the results suggest that L-glutamine is better than L-alanine, as gluconeogenic substrate in livers of hypoglycaemic weaned rats.
Oliveira-Yamashita
Fabiana
F
Department of Pharmacy and Pharmacology, State University of Maringá, Maringá, PR, Brazil.
Garcia
Rosangela Fernandes
RF
Felisberto-Junior
Antonio Machado
AM
Curi
Rui
R
Bazotte
Roberto Barbosa
RB
D000409:Alanine / Q000378:metabolism / Q000494:pharmacology*; D000818:Animals; D005215:Fasting / Q000378:metabolism*; D005943:Gluconeogenesis / Q000187:drug effects*; D005947:Glucose / Q000378:metabolism; D005973:Glutamine / Q000378:metabolism / Q000494:pharmacology*; D005990:Glycerol / Q000378:metabolism; D006946:Hyperinsulinism / Q000139:chemically induced / Q000378:metabolism; D007003:Hypoglycemia / Q000139:chemically induced / Q000378:metabolism*; D007004:Hypoglycemic Agents / Q000009:adverse effects* / Q000494:pharmacology; D007328:Insulin / Q000009:adverse effects* / Q000494:pharmacology; D019344:Lactic Acid / Q000378:metabolism; D008099:Liver / Q000378:metabolism*; D008297:Male; D010477:Perfusion; D019289:Pyruvic Acid / Q000378:metabolism; D051381:Rats; D013997:Time Factors; D014886:Weaning
D007004:Hypoglycemic Agents; D007328:Insulin; D005973:Glutamine; D019344:Lactic Acid; D019289:Pyruvic Acid; D005947:Glucose; D000409:Alanine; D005990:Glycerol