Inhibition and labeling of the rat renal Na+/H+-exchanger by an antagonist of muscarinic acetylcholine receptors.
A covalently binding label for muscarinic acetylcholine receptors, propylbenzilylcholine mustard (PrBCM), irreversibly inhibits the Na+/H+ exchanger in rat renal brush-border membrane vesicles. Substrates of the antiporter, Na+ and Li+, as well as inhibitors, amiloride, 5-(N-ethyl-N-isopropyl)amiloride (EIPA) and propranolol, protect the antiporter from inactivation by PrBCM. With [3H]PrBCM a band with an app. Mr of 65 kDa is predominantly labeled. Amiloride protects this band from labeling with [3H]PrBCM and [14C]-N,N'-dicyclohexylcarbodiimide (DCCD) proving its identity with the renal Na+/H+ exchanger. Our data reveal a specific interaction of PrBCM with the Na+/H+ exchanger and suggest structural relations between antiporter and receptors.
Friedrich
T
T
Department of Medical Chemistry, Kyoto University Faculty of Medicine, Japan.
Burckhardt
G
G
D000165:Acridine Orange; D000345:Affinity Labels; D000584:Amiloride / Q000031:analogs & derivatives / Q000494:pharmacology; D000818:Animals; D002352:Carrier Proteins / Q000037:antagonists & inhibitors* / Q000378:metabolism; D002794:Choline / Q000031:analogs & derivatives*; D003978:Diazomethane / Q000031:analogs & derivatives / Q000378:metabolism; D004024:Dicyclohexylcarbodiimide / Q000378:metabolism / Q000494:pharmacology; D020120:Iodocyanopindolol / Q000031:analogs & derivatives*; D007668:Kidney / Q000378:metabolism*; D008094:Lithium / Q000494:pharmacology; D008297:Male; D008871:Microvilli / Q000378:metabolism; D010869:Pindolol / Q000031:analogs & derivatives / Q000378:metabolism; D011433:Propranolol / Q000494:pharmacology; D011438:Propylbenzilylcholine Mustard / Q000378:metabolism / Q000494:pharmacology*; D051381:Rats; D011919:Rats, Inbred Strains; D011976:Receptors, Muscarinic / Q000187:drug effects*; D012964:Sodium / Q000494:pharmacology; D017923:Sodium-Hydrogen Exchangers; D000254:Sodium-Potassium-Exchanging ATPase / Q000378:metabolism
D000345:Affinity Labels; D002352:Carrier Proteins; D011976:Receptors, Muscarinic; D017923:Sodium-Hydrogen Exchangers; C058075:iodocyanopindolol diazirine; D011438:Propylbenzilylcholine Mustard; D004024:Dicyclohexylcarbodiimide; D003978:Diazomethane; D000584:Amiloride; D020120:Iodocyanopindolol; D008094:Lithium; D012964:Sodium; D011433:Propranolol; D010869:Pindolol; D000254:Sodium-Potassium-Exchanging ATPase; D000165:Acridine Orange; D002794:Choline; C039614:ethylisopropylamiloride