Evidence for two Ca2(+)-mobilizing purinoceptors on rat hepatocytes.
Aequorin measurements of cytosolic free Ca2+ in single rat hepatocytes show that ADP and ATP, thought to act through the same P2Y purinoceptor, elicited very different responses in the majority of cells tested. ADP invariably induced transients of short duration (approx. 9 s), whereas ATP induced either similar transients or transients with a much longer duration (approx. 49 s). We explain this variability in terms of two separate purinoceptors on rat hepatocytes, one of which responds to either ATP or ADP to generate free-Ca2+ transients of short duration, and the other responds to ATP only, with transients of longer duration.
Dixon
C J
CJ
Department of Human Anatomy and Cell Biology, University of Liverpool, U.K.
Woods
N M
NM
Cuthbertson
K S
KS
Cobbold
P H
PH
D000244:Adenosine Diphosphate / Q000494:pharmacology; D000255:Adenosine Triphosphate / Q000031:analogs & derivatives / Q000494:pharmacology; D000331:Aequorin; D000818:Animals; D002118:Calcium / Q000378:metabolism*; D008099:Liver / Q000187:drug effects / Q000378:metabolism*; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D011983:Receptors, Purinergic / Q000378:metabolism*
D011983:Receptors, Purinergic; C022571:adenosine 5'-O-(3-thiotriphosphate); D000331:Aequorin; D000244:Adenosine Diphosphate; D000255:Adenosine Triphosphate; D002118:Calcium