Kidney Week

Abstract: SA-PO364

The Relationship between Intrarenal Dopamine and Intrarenal Renin-Angiotensin System in CKD Patients Is Dependent on Renal Function

Session Information

• CKD: Risk Factors for Incidence and Progression - III
  November 04, 2017 | Location: Hall H, Morial Convention Center
  Abstract Time: 10:00 AM - 10:00 AM

Category: Chronic Kidney Disease (Non-Dialysis)

• 301 CKD: Risk Factors for Incidence and Progression

Authors

• Matsuyama, Takashi, Hamamatsu University School of Medicine, Numazu, Japan

Takashi Matsuyama,

• Ohashi, Naro, Hamamatsu University School of Medicine, Numazu, Japan

Naro Ohashi,

• Ishigaki, Sayaka, Hamamatsu University School of Medicine, Numazu, Japan

Sayaka Ishigaki,

• Isobe, Shinsuke, Hamamatsu University School of Medicine, Numazu, Japan

Shinsuke Isobe,

• Tsuji, Naoko, Hamamatsu University School of Medicine , Hamamatsu, Shizuoka, Japan

Naoko Tsuji,

• Fujikura, Tomoyuki, Hamamatsu university school of medicine, Munich, Germany

Tomoyuki Fujikura,

• Tsuji, Takayuki, Hamamatsu University School of Medicine, Numazu, Japan

Takayuki Tsuji,

• Kato, Akihiko, Hamamatsu University Hospital, Hamamatsu, SHIZUOKA, Japan

Akihiko Kato,

• Yasuda, Hideo, Hamamatsu University School of Medicine, Numazu, Japan

Hideo Yasuda,

Background

The mechanisms to activate intrarenal renin-angiotensin system (RAS) depend on the conditions of kidney diseases. In the angiotensin II (AngII) infusion models, the circulating AngII is filtered into renal tubular lumens and activates intrarenal RAS. Intrarenal dopamine system activation was shown to reduce angiotensinogen (AGT) expression in the proximal tubules and suppress intrarenal RAS activity. In the chronic kidney disease (CKD) models where filtered plasma AGT into the tubular lumens due to glomerular injury activates intrarenal RAS, the relationship between intrarenal dopamine system and intrarenal RAS in CKD models has not been clarified. Therefore, we performed this study to determine the mutual relationship in CKD patients.

Methods

We recruited 46 CKD patients (age: 51.1 ± 20.0 years old, 16 males, causes of CKD: chronic glomerulonephritis; 34, diabetic nephropathy; 2, nephrosclerosis; 4, or others; 6) without undergoing dialysis or taking RAS blockers. The urinary dopamine (U-DOPA) excretion as an indicator of intrarenal dopamine activity and the urinary AGT (U-AGT) excretion as a surrogate marker of intrarenal RAS activity were measured, and the relationships were investigated.

Results

U-DOPA excretion levels in patients with CKD stage 5 were significantly lower than those in patients with other CKD stages, and U-DOPA excretion levels tended to decrease as the CKD stages progressed. Conversely, U-AGT excretion levels in patients with CKD stage 5 were significantly higher than those in patients with CKD stages 1 to 3, and tended to increase as the CKD stages progressed. U-DOPA excretion levels were significantly and negatively correlated with U-AGT excretion levels (r=-0.42, p<0.01) and significantly and positively correlated with estimated glomerular filtration rate (eGFR) (r=0.64, p<0.01). Multiple regression analysis revealed that U-DOPA excretion levels were associated with U-AGT excretion levels after adjustment of age, sex, and body mass index (β =-0.34, p=0.025). However, the correlation disappeared when eGFR was additionally adjusted (β=-0.057, p=0.70).

Conclusion

The negative correlation between intrarenal dopamine system and intrarenal RAS system in CKD patients is affected by renal function.