Effects of testosterone on glomerular growth after uninephrectomy.
BACKGROUND
Renal functional prognosis is consistently more adverse in male individuals with renal disease. Male animals develop more marked proteinuria and glomerulosclerosis in several models of renal damage. Renal and glomerular growth are important permissive factors for progression of renal failure.


OBJECTIVE
To investigate the influence of testosterone on renal and glomerular growth.


METHODS
Renal compensatory growth after uninephrectomy (UNX) was chosen as a model of renal growth. The effect of testosterone was assessed in control male, in orchidectomized (OX) male, and in ovariectomized (OV) female SD rats. Observation time was 10 months.


METHODS
Albuminuria by nephelometry; glomerular diameter, glomerular tuft area, renal zonal analysis by quantitative stereology. Testosterone and dihydroxytestosterone by gas chromatography and RIA.


RESULTS
In sham-operated male rats, testosterone administration did not change the (left) kidney:body-weight ratio after uninephrectomy. In contrast, in OX male rats, testosterone administration caused a significant increase in kidney:body-weight ratio and in albuminuria. In these animals, glomerular diameter and outer stripe width were significantly lower in OX rats than in sham-operated controls. Glomerular volume and outer stripe width in OX animals were significantly higher after uninephrectomy (UNX) and were further increased in OX-UNX animals by administration of testosterone. Similar effects on glomerular diameter, cortical width (single) kidney:body-weight ratio were seen when OV female rats were treated with testosterone.


CONCLUSIONS
After gonadal ablation, administration of testosterone amplifies compensatory glomerular and tubular growth in uninephrectomized male and female rats, i.e. testosterone is a permissive factor. Stimulation of glomerular growth may favour development of glomerulosclerosis.
Department of Internal Medicine, Ruperto Carola University, Heidelberg, Germany.
M
M
Zeier
R
R
Schönherr
K
K
Amann
E
E
Ritz
D000222:Adaptation, Physiological / Q000187:drug effects; D000818:Animals; D005260:Female; D007678:Kidney Glomerulus / Q000187:drug effects* / Q000254:growth & development; D008297:Male; D009392:Nephrectomy / Q000379:methods*; D009919:Orchiectomy; D010052:Ovariectomy; D011184:Postoperative Period; D051381:Rats; D017207:Rats, Sprague-Dawley; D013739:Testosterone / Q000494:pharmacology*
D013739:Testosterone