Effect of a prostacyclin analogue, iloprost, on urinary aquaporin-2 excretion in humans.
The regulation of aquaporin-2 (AQP2) water channel excretion in the collecting duct depends mainly on the action of vasopressin (AVP). Recently, however, other regulatory factors have been identified: atrial natriuretic factor, oxytocin and prostaglandins. In healthy volunteers (5 males, 5 females; mean age 23 +/- 3 years) we therefore evaluated the effect of a stable analogue of prostacyclin-2 (PGI(2)), iloprost, on renal function and on the urinary excretion of AQP2 (U-AQP2). After 6 h of iloprost infusion, U-AQP2 increased from 0.8 +/- 0.15 to 1.8 +/- 0.2 pmol/mg creatinine (p < 0.001), while the urinary flow rate increased from 1.4 +/- 0.2 to 1.8 +/- 4 (p < 0.01). No significant change was found in the AVP serum concentration, with a basal value of 3.17 +/- 0.12 vs. 3.15 +/- 0.12 pg/ml after 6 h of prostacyclin infusion. All the values returned to pre-study levels after a recovery period of 6 h. In conclusion, the PGI(2) analogue, iloprost, can induce U-AQP2 excretion independent of AVP.
Buemi
Michele
M
Chair of Nephrology, Department of Internal Medicine, University of Messina, Italy.
Di Pasquale
Giuseppe
G
Ruello
Antonella
A
Floccari
Fulvio
F
Aloisi
Carmela
C
Latassa
Giuseppe
G
Corsonello
Andrea
A
Sturiale
Alessio
A
Corica
Francesco
F
Frisina
Nicola
N
D015121:6-Ketoprostaglandin F1 alpha / Q000652:urine; D000328:Adult; D051399:Aquaporin 2; D051403:Aquaporin 6; D020346:Aquaporins / Q000652:urine*; D001127:Arginine Vasopressin / Q000652:urine; D003404:Creatinine / Q000378:metabolism; D015232:Dinoprostone / Q000652:urine; D011464:Epoprostenol / Q000031:analogs & derivatives; D005260:Female; D006801:Humans; D016285:Iloprost / Q000008:administration & dosage*; D008297:Male; D009994:Osmolar Concentration; D014665:Vasodilator Agents / Q000008:administration & dosage*
C496023:AQP2 protein, human; D051399:Aquaporin 2; D051403:Aquaporin 6; D020346:Aquaporins; D014665:Vasodilator Agents; D001127:Arginine Vasopressin; D015121:6-Ketoprostaglandin F1 alpha; D003404:Creatinine; D011464:Epoprostenol; D016285:Iloprost; D015232:Dinoprostone