title: Circadian rhythm of urinary potassium excretion during treatment with an angiotensin receptor blocker.
abstract: BACKGROUND
  We have reported that the circadian rhythm of urinary potassium excretion (U(K)V) is determined by the rhythm of urinary sodium excretion (U(Na)V) in patients with chronic kidney disease (CKD). We also reported that treatment with an angiotensin receptor blocker (ARB) increased the U(Na)V during the daytime, and restored the non-dipper blood pressure (BP) rhythm into a dipper pattern. However, the circadian rhythm of U(K)V during ARB treatment has not been reported.
  
  
  METHODS
  Circadian rhythms of U(Na)V and U(K)V were examined in 44 patients with CKD undergoing treatment with ARB.
  
  
  RESULTS
  Whole-day U(Na)V was not altered by ARB whereas whole-day U(K)V decreased. Even during the ARB treatment, the significant relationship persisted between the night/day ratios of U(Na)V and U(K)V (r=0.56, p<0.0001). Whole-day U(K)V/U(Na)V ratio (p=0.0007) and trans-tubular potassium concentration gradient (p=0.002) were attenuated but their night/day ratios remained unchanged. The change in the night/day U(K)V ratio correlated directly with the change in night/day U(Na)V ratio (F=20.4) rather than with the changes in aldosterone, BP or creatinine clearance.
  
  
  CONCLUSIONS
  The circadian rhythm of U(K)V was determined by the rhythm of UNaV even during ARB treatment. Changes in the circadian U(K)V rhythm were not determined by aldosterone but by U(Na)V.
authors: Department of Cardio-Renal Medicine and Hypertension, Nagoya City University Graduate School of Medical Sciences, Japan.
authors: Yoshiaki
authors: Y
authors: Ogiyama
authors: Department of Cardio-Renal Medicine and Hypertension, Nagoya City University Graduate School of Medical Sciences, Japan.
authors: Toshiyuki
authors: T
authors: Miura
authors: Department of Cardio-Renal Medicine and Hypertension, Nagoya City University Graduate School of Medical Sciences, Japan.
authors: Shuichi
authors: S
authors: Watanabe
authors: Department of Cardio-Renal Medicine and Hypertension, Nagoya City University Graduate School of Medical Sciences, Japan.
authors: Daisuke
authors: D
authors: Fuwa
authors: Department of Cardio-Renal Medicine and Hypertension, Nagoya City University Graduate School of Medical Sciences, Japan.
authors: Tatsuya
authors: T
authors: Tomonari
authors: Department of Cardio-Renal Medicine and Hypertension, Nagoya City University Graduate School of Medical Sciences, Japan.
authors: Keisuke
authors: K
authors: Ota
authors: Department of Cardio-Renal Medicine and Hypertension, Nagoya City University Graduate School of Medical Sciences, Japan.
authors: Yoko
authors: Y
authors: Kato
authors: Department of Cardio-Renal Medicine and Hypertension, Nagoya City University Graduate School of Medical Sciences, Japan.
authors: Tadashi
authors: T
authors: Ichikawa
authors: Department of Cardio-Renal Medicine and Hypertension, Nagoya City University Graduate School of Medical Sciences, Japan.
authors: Yuichi
authors: Y
authors: Shirasawa
authors: Department of Cardio-Renal Medicine and Hypertension, Nagoya City University Graduate School of Medical Sciences, Japan.
authors: Akinori
authors: A
authors: Ito
authors: Department of Cardio-Renal Medicine and Hypertension, Nagoya City University Graduate School of Medical Sciences, Japan.
authors: Atsuhiro
authors: A
authors: Yoshida
authors: Department of Cardio-Renal Medicine and Hypertension, Nagoya City University Graduate School of Medical Sciences, Japan m-fukuda@med.nagoya-cu.ac.jp.
authors: Michio
authors: M
authors: Fukuda
authors: Department of Cardio-Renal Medicine and Hypertension, Nagoya City University Graduate School of Medical Sciences, Japan.
authors: Genjiro
authors: G
authors: Kimura
mesh_terms: D057911:Angiotensin Receptor Antagonists / Q000494:pharmacology*; D002940:Circadian Rhythm / Q000187:drug effects*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011188:Potassium / Q000652:urine*; D012964:Sodium / Q000652:urine
chemical_list: D057911:Angiotensin Receptor Antagonists; D012964:Sodium; D011188:Potassium
keywords: Circadian rhythm; angiotensin receptor blocker; chronic kidney disease; sodium; urinary potassium excretion