The hyperpolarization-activated cyclic nucleotide-gated HCN2 channel transports ammonium in the distal nephron
Por:
Carrisoza-Gaytán R., Rangel C., Salvador C., Saldana-Meyer, R, Escalona C., Satlin L.M., Liu W., Zavilowitz B., Trujillo J., Bobadilla N.A., Escobar L.I.
Publicada:
1 oct 2011
Categoría:
Nephrology
Resumen:
Recent studies have identified Rhesus proteins as important molecules for ammonia transport in acid-secreting intercalated cells in the distal nephron. Here, we provide evidence for an additional molecule that can mediate NH3/NH4 excretion, the subtype 2 of the hyperpolarization-activated cyclic nucleotide-gated channel family (HCN2), in collecting ducts in rat renal cortex and medulla. Chronic metabolic acidosis in rats did not alter HCN2 protein expression but downregulated the relative abundance of HCN2 mRNA. Its cDNA was identical to the homolog from the brain and the protein was post-translationally modified by N-type glycosylation. Electrophysiological recordings in Xenopus oocytes injected with HCN2 cRNA found that potassium was transported better than ammonium, each of which was transported significantly better than sodium, criteria that are compatible with a role for HCN2 in ammonium transport. In microperfused rat outer medullary collecting duct segments, the initial rate of
Filiaciones:
Carrisoza-Gaytán R.:
Univ Nacl Autonoma Mexico, Dept Fisiol, Fac Med, Mexico City 04510, DF, Mexico
Rangel C.:
Univ Nacl Autonoma Mexico, Dept Fisiol, Fac Med, Mexico City 04510, DF, Mexico
Salvador C.:
Univ Nacl Autonoma Mexico, Dept Fisiol, Fac Med, Mexico City 04510, DF, Mexico
Saldana-Meyer, R:
Univ Nacl Autonoma Mexico, Dept Fisiol, Fac Med, Mexico City 04510, DF, Mexico
Escalona C.:
Univ Nacl Autonoma Mexico, Dept Fisiol, Fac Med, Mexico City 04510, DF, Mexico
Satlin L.M.:
Department of Pediatrics, Mount Sinai School of Medicine, New York, NY, United States
Liu W.:
Department of Pediatrics, Mount Sinai School of Medicine, New York, NY, United States
Zavilowitz B.:
Department of Pediatrics, Mount Sinai School of Medicine, New York, NY, United States
Trujillo J.:
Univ Nacl Autonoma Mexico, Inst Nacl Ciencis Med & Nutr, Inst Invest Biomed, Unidad Fisiol Mol, Mexico City 04510, DF, Mexico
Bobadilla N.A.:
Univ Nacl Autonoma Mexico, Inst Nacl Ciencis Med & Nutr, Inst Invest Biomed, Unidad Fisiol Mol, Mexico City 04510, DF, Mexico
Escobar L.I.:
Univ Nacl Autonoma Mexico, Dept Fisiol, Fac Med, Mexico City 04510, DF, Mexico
All Open Access, Bronze
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