TY - JOUR
T1 - Expression of aquaporin-2 in the collecting duct and responses to tolvaptan
AU - Kakeshita, Kota
AU - Koike, Tsutomu
AU - Imamura, Teruhiko
AU - Fujioka, Hayato
AU - Yamazaki, Hidenori
AU - Kinugawa, Koichiro
PY - 2021/2/1
Y1 - 2021/2/1
N2 - Tolvaptan, a vasopressin type-2 receptor antagonist, is indicated for fluid retention. It is considered that the response to tolvaptan reduces as renal function deteriorates, whereas we sometimes experience "non-responders" to tolvaptan despite well-preserved renal function. While the expression of aquaporin-2 might be a key to response to tolvaptan, detailed mechanism of refractoriness to tolvaptan remains unknown. We experienced two patients with congestive heart failure and diabetic nephropathy, in whom the responses to tolvaptan were uniquely opposite. In one case, immunohistochemical staining showed expression of aquaporin-2 in the collecting duct despite severely reduced renal function, followed by the good response to tolvaptan with increased urine output. In another case, immunohistochemical staining showed absence of aquaporin-2 with infiltration of inflammatory cells in the kidney medulla despite relatively preserved renal function, followed by refractoriness to tolvaptan without any increase in urine output. Inactivated aquaporin-2 expression in the collecting duct, which was for example caused by pre-clinical urinary infection as our latter case, might have an association with refractoriness to tolvaptan.
AB - Tolvaptan, a vasopressin type-2 receptor antagonist, is indicated for fluid retention. It is considered that the response to tolvaptan reduces as renal function deteriorates, whereas we sometimes experience "non-responders" to tolvaptan despite well-preserved renal function. While the expression of aquaporin-2 might be a key to response to tolvaptan, detailed mechanism of refractoriness to tolvaptan remains unknown. We experienced two patients with congestive heart failure and diabetic nephropathy, in whom the responses to tolvaptan were uniquely opposite. In one case, immunohistochemical staining showed expression of aquaporin-2 in the collecting duct despite severely reduced renal function, followed by the good response to tolvaptan with increased urine output. In another case, immunohistochemical staining showed absence of aquaporin-2 with infiltration of inflammatory cells in the kidney medulla despite relatively preserved renal function, followed by refractoriness to tolvaptan without any increase in urine output. Inactivated aquaporin-2 expression in the collecting duct, which was for example caused by pre-clinical urinary infection as our latter case, might have an association with refractoriness to tolvaptan.
KW - Arginine vasopressin
KW - Diuretics
KW - Responder
UR - http://www.scopus.com/inward/record.url?scp=85100359610&partnerID=8YFLogxK
U2 - 10.1007/s13730-020-00518-1
DO - 10.1007/s13730-020-00518-1
M3 - 学術論文
C2 - 32779125
AN - SCOPUS:85100359610
SN - 2192-4449
VL - 10
SP - 69
EP - 73
JO - CEN case reports
JF - CEN case reports
IS - 1
ER -