Adenosine induces System A amino acid transport in cultured rat hepatocytes.
Adenosine caused a 2.5-fold increase in the sodium-dependent uptake of 2-aminoisobutyric acid in rat hepatocytes in primary culture following incubation for 3 h. The range of stimulating concentrations of adenosine corresponded to that of cAMP formation. Adenosine increased the Vmax of the transport without altering the Km for 2-aminoisobutyric acid. These effects of adenosine were abolished by actinomycin D. N6-L-Phenylisopropyladenosine also caused twofold increase in the amino acid transport. These findings suggest that adenosine induces System A amino acid transport in a transcription-dependent manner, and the P1-purinergic receptors are mainly involved in this action of the nucleoside.
Second Department of Internal Medicine, Osaka University Medical School.
H
H
Kiyokawa
H
H
Fukui
H
H
Mizuguchi
A
A
Kubo
N
N
Kono
S
S
Tarui
H
H
Wada
D000241:Adenosine / Q000494:pharmacology*; D000596:Amino Acids / Q000378:metabolism*; D000621:Aminoisobutyric Acids / Q000378:metabolism; D000818:Animals; D001693:Biological Transport, Active / Q000187:drug effects; D002478:Cells, Cultured; D007700:Kinetics; D008099:Liver / Q000187:drug effects* / Q000378:metabolism; D051381:Rats; D011983:Receptors, Purinergic / Q000187:drug effects / Q000378:metabolism
D000596:Amino Acids; D000621:Aminoisobutyric Acids; D011983:Receptors, Purinergic; C100049:2-aminoisobutyric acid; D000241:Adenosine