Purinergic modulation of Na(+),K(+),Cl(-) cotransport and MAP kinases is limited to C11-MDCK cells resembling intercalated cells from collecting ducts.
We demonstrated recently that in renal epithelial cells from collecting ducts of Madin-Darby canine kidneys (MDCK), Na(+),K(+), Cl(-) cotransport is inhibited up to 50% by ATP via its interaction with P(2Y) purinoceptors (Biochim. Biophys. Acta 1998. 1369:233-239). In the present study we examined which type of renal epithelial cells possesses the highest sensitivity of Na(+),K(+),Cl(-) cotransport to purinergic regulation. We did not observe any effect of ATP on Na(+),K(+),Cl(-) cotransport in renal epithelial cells from proximal and distal tubules, whereas in renal epithelial cells from rabbit and rat collecting ducts ATP decreased the carrier's activity by approximately 30%. ATP did not affect Na(+),K(+),Cl(-) cotransport in C7 subtype MDCK cells possessing the properties of principal cells but led to approximately 85% inhibition of this carrier in C11-MDCK cells in which intercalated cells are highly abundant. Both C7- and C11-MDCK exhibited ATP-induced IP(3) and cAMP production and transient elevation of [Ca(2+)](i). In contrast to the above-listed signaling systems, ATP-induced phosphorylation of ERK and JNK MAP kinases was observed in C11-MDCK only. Thus, our results reveal that regulation of renal Na(+),K(+),Cl(-) cotransport by P(2Y) receptors is limited to intercalated cells from collecting ducts and indicate the involvement of the MAP kinase cascade in purinergic control of this ion carrier's activity.
Orlov
S N
SN
Centre de recherche du CHUM, University of Montreal, Montreal, Quebec, Canada.
Dulin
N O
NO
Gagnon
F
F
Gekle
M
M
Douglas
J G
JG
Schwartz
J H
JH
Hamet
P
P
D000255:Adenosine Triphosphate / Q000378:metabolism; D000818:Animals; D002352:Carrier Proteins / Q000378:metabolism*; D002460:Cell Line; D002712:Chlorides / Q000378:metabolism*; D000242:Cyclic AMP / Q000378:metabolism; D004285:Dogs; D007685:Kidney Tubules, Collecting / Q000378:metabolism*; D007687:Kidney Tubules, Proximal / Q000378:metabolism; D008565:Membrane Proteins / Q000378:metabolism*; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism*; D011188:Potassium / Q000378:metabolism*; D011817:Rabbits; D051381:Rats; D012413:Rubidium / Q000378:metabolism; D012964:Sodium / Q000378:metabolism*; D028021:Sodium-Potassium-Chloride Symporters
D002352:Carrier Proteins; D002712:Chlorides; D008565:Membrane Proteins; D028021:Sodium-Potassium-Chloride Symporters; D000255:Adenosine Triphosphate; D012964:Sodium; D000242:Cyclic AMP; D020928:Mitogen-Activated Protein Kinases; D012413:Rubidium; D011188:Potassium