KEGG   PATHWAY: ko04966
Entry
ko04966                     Pathway                                

Name
Collecting duct acid secretion
Description
One of the important roles of the collecting duct segment of the kidney nephron is acid secretion. As daily food intake loads acid into the body, urinary acid excretion is essential, and urine pH can drop as low as 4.5. The alpha-intercalated cell of collecting duct is the main responsible for hydrogen secretion into the urine. The carbon dioxide, which is generated in the cells and enters from the blood, is changed to carbonic acid. This carbonic acid is divided into hydrogen ion and bicarbonate ion. Intracellular CA II catalyses the formation of these ions. The hydrogen ion is secreted into the lumen by the luminal H(+)-ATPase. The bicarbonate ion is transported to the blood side by the anion exchanger type 1. Hydrogen ion in the lumen is trapped by urinary buffers. These include ammonium and phosphate.
Class
Organismal Systems; Excretory system
Pathway map
ko04966  Collecting duct acid secretion
ko04966

Disease
H00241  Combined proximal and distal renal tubular acidosis
H00428  Distal renal tubular acidosis (RTA type 1)
H02310  Renal tubular acidosis
Orthology
K18245  carbonic anhydrase 2 [EC:4.2.1.1]
K02145  V-type H+-transporting ATPase subunit A [EC:7.1.2.2]
K02147  V-type H+-transporting ATPase subunit B
K02152  V-type H+-transporting ATPase subunit G
K02148  V-type H+-transporting ATPase subunit C
K02149  V-type H+-transporting ATPase subunit D
K02150  V-type H+-transporting ATPase subunit E
K02151  V-type H+-transporting ATPase subunit F
K02153  V-type H+-transporting ATPase subunit e
K02154  V-type H+-transporting ATPase subunit a
K02155  V-type H+-transporting ATPase 16kDa proteolipid subunit
K02146  V-type H+-transporting ATPase subunit d
K01542  H+/K+-exchanging ATPase subunit alpha [EC:7.2.2.19]
K01543  H+/K+-exchanging ATPase subunit beta [EC:7.2.2.19]
K06573  solute carrier family 4 (anion exchanger), member 1
K13627  solute carrier family 12 (potassium/chloride transporter), member 7
K05018  chloride channel Kb
Compound
C00001  H2O
C00011  CO2
C00014  Ammonia
C00080  H+
C00238  Potassium cation
C00288  HCO3-
C00698  Cl-
C01353  Carbonic acid
Reference
  Authors
Wagner CA, Kovacikova J, Stehberger PA, Winter C, Benabbas C, Mohebbi N
  Title
Renal acid-base transport: old and new players.
  Journal
Nephron Physiol 103:p1-6 (2006)
DOI:10.1159/000090217
Reference
  Authors
Wagner CA, Devuyst O, Bourgeois S, Mohebbi N
  Title
Regulated acid-base transport in the collecting duct.
  Journal
Pflugers Arch 458:137-56 (2009)
DOI:10.1007/s00424-009-0657-z
Reference
  Authors
Koeppen BM
  Title
The kidney and acid-base regulation.
  Journal
Adv Physiol Educ 33:275-81 (2009)
DOI:10.1152/advan.00054.2009
Reference
PMID:9550618
  Authors
Hayashi M
  Title
Physiology and pathophysiology of acid-base homeostasis in the kidney.
  Journal
Intern Med 37:221-5 (1998)
DOI:10.2169/internalmedicine.37.221
Reference
  Authors
Fry AC, Karet FE
  Title
Inherited renal acidoses.
  Journal
Physiology (Bethesda) 22:202-11 (2007)
DOI:10.1152/physiol.00044.2006
Reference
  Authors
Pereira PC, Miranda DM, Oliveira EA, Silva AC
  Title
Molecular pathophysiology of renal tubular acidosis.
  Journal
Curr Genomics 10:51-9 (2009)
DOI:10.2174/138920209787581262
Reference
  Authors
Rodriguez-Soriano J
  Title
New insights into the pathogenesis of renal tubular acidosis--from functional to molecular studies.
  Journal
Pediatr Nephrol 14:1121-36 (2000)
DOI:10.1007/s004670000407
Reference
  Authors
Alper SL
  Title
Genetic diseases of acid-base transporters.
  Journal
Annu Rev Physiol 64:899-923 (2002)
DOI:10.1146/annurev.physiol.64.092801.141759
Related
pathway
ko04530  Tight junction

DBGET integrated database retrieval system