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Organic anion secretion in polycystic kidney disease
1Department of Physiology and Biophysics, Indiana University School of Medicine, Indianapolis 46202, USA.
Journal of the American Society of Nephrology : JASN
|August 1, 1997
Summary
Organic anion secretion by kidney cysts does not significantly contribute to fluid accumulation in polycystic kidney disease. This study found that while cysts can secrete organic anions, this process is not a major driver of cyst growth in rats.
Area of Science:
- Nephrology
- Renal Physiology
- Cell Biology
Background:
- Polycystic kidney disease (PKD) is characterized by cyst formation and fluid accumulation in the kidneys.
- The role of organic anion secretion in the pathogenesis of PKD-related cystogenesis remains unclear.
Purpose of the Study:
- To investigate whether organic anion secretion contributes to fluid accumulation in kidney cysts in a rat model of autosomal dominant polycystic kidney disease (ADPKD).
Main Methods:
- Utilized clearance and micropuncture studies in young Han:SPRD cystic rats and healthy controls.
- Employed fluorescence microscopy to assess organic anion transport (sulfonefluorescein) in cysts.
- Conducted stationary microperfusion techniques to evaluate tubular secretion.
Main Results:
- No significant differences in glomerular filtration rate (GFR) or maximal p-aminohippurate (PAH) secretion rates were observed between cystic and healthy rats.
- Most proximal cysts demonstrated the ability to secrete sulfonefluorescein, an organic anion.
- Isolated tubule and cyst segments failed to accumulate fluid when PAH was administered.
Conclusions:
- Proximal cystic epithelia in the Han:SPRD rat model retain the capacity for organic anion secretion.
- Organic anion secretion does not appear to be a substantial contributor to cyst fluid accumulation in this PKD model.
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