Titre du document / Document title

Effect of prolonged treatment with tyramine on glucose tolerance in streptozotocin-induced diabetic rats

Auteur(s) / Author(s)

VISENTIN V. ; MARQ P. ; BOUR S. ; SUBRA C. ; PREVOT D. ; MORIN N. ; VALET P. ; MONJE M. C. ; NEPVEU F. ; CARPENE C. ;

Résumé / Abstract

The biogenic amine tyramine has been reported to stimulate in vitro glucose transport in adipocytes, cardiomyocytes and skeletal muscle, and to improve in vivo glucose utilization in rats. These effects were dependent on amine oxidation, since they were blocked by inhibitors of monoamine oxidase (MAO) and semicarbazide-sensitive amine oxidase (SSAO). We thus tested in this work whether a prolonged treatment with tyramine could improve glucose tolerance in streptozotocin-induced diabetic rats. First, tyramine content of standard rodent chow was determined by HPLC and daily tyramine intake of control rats was estimated to be around 26 pmol/kg body weight. Then, tyramine was administred during 3 weeks in streptozotocin-induced diabetic rats at 29 pmol/kg by daily i.p. injection alone or together with vanadate 0.02 pmol/kg. In another group of diabetic rats, tyramine was subcutaneously delivered at 116 pmol/kg/day by osmotic minipumps. All tyramine treatments resulted in a decrease of the hyperglycemic responses to an i.p. glucose load. Adipocytes isolated from either untreated or treated diabetic rats were sensitive to the stimulation of glucose uptake by tyramine. However, diabetic animals receiving tyramine for three weeks did not recover from their hyperglycemia, hypoinsulinemia and glucosuria. These results show that the improvement of glucose tolerance induced by prolonged tyramine administration occurs in an insulin-depleted model and probably results from peripheral insulin-like actions of the oxidation of MAO/SSAO substrates, such as the stimulation of glucose uptake into adipocytes.

Revue / Journal Title

Journal of physiology and biochemistry   ISSN 1138-7548   CODEN JPBIF2 

Source / Source

2003, vol. 59, n^o3, pp. 225-232 [8 page(s) (article)]

Langue / Language

Anglais

Editeur / Publisher

Universidad de Navarra, Pamplona, ESPAGNE  (1996) (Revue)

Localisation / Location

INIST-CNRS, Cote INIST : 3161, 35400011595296.0100