Altered vitamin B6 homeostasis during aminophylline infusion in the beagle dog.
The effect of intravenous infusion of aminophylline, a strong inhibitor of pyridoxal kinase, on intra- and extracellular vitamin B6 homeostasis was investigated in four beagle dogs. Plasma and erythrocyte pyridoxal levels increased by 118% and 117% respectively after 3 hours of aminophylline infusion, (4 mg/kg body weight/hour), however, infusion of beta-hydroxyethyltheophylline, which does not inhibit pyridoxal kinase, had no effect on either intra- or extracellular vitamin B6 aldehyde derivative levels. It is suggested that theophylline induced pyridoxal kinase inhibition resulted in a disturbed equilibrium between pyridoxal and pyridoxal 5'-phosphate.
Delport
R
R
Department of Chemical Pathology, University of Pretoria, South Africa.
Ubbink
J B
JB
Bosman
H
H
Bissbort
S
S
Vermaak
W J
WJ
D000469:Alkaline Phosphatase / Q000097:blood / Q000378:metabolism; D000628:Aminophylline / Q000008:administration & dosage / Q000494:pharmacology*; D000818:Animals; D001993:Bronchodilator Agents / Q000008:administration & dosage / Q000494:pharmacology; D004285:Dogs; D004912:Erythrocytes / Q000187:drug effects / Q000378:metabolism; D006706:Homeostasis; D007262:Infusions, Intravenous; D011731:Pyridoxal Kinase / Q000037:antagonists & inhibitors; D011736:Pyridoxine / Q000097:blood / Q000378:metabolism*; D012709:Serum Albumin / Q000378:metabolism; D013806:Theophylline / Q000008:administration & dosage / Q000031:analogs & derivatives / Q000494:pharmacology
D001993:Bronchodilator Agents; D012709:Serum Albumin; D000628:Aminophylline; D013806:Theophylline; D011731:Pyridoxal Kinase; D000469:Alkaline Phosphatase; D011736:Pyridoxine; C008749:etofylline