Protective effect of female gender on the development of albuminuria in a polygenetic rat model is enhanced further by replacement of a major autosomal QTL.
Clinical and experimental studies indicate that the progression of renal disease is faster in males than females. These observations are corroborated by a sexual dimorphism observed in the polygenetic MWF (Munich Wistar Frömter) rat model. The age-dependent spontaneous progression of increased UAE (urinary albumin excretion) in male MWF rats is influenced by multiple QTLs (quantitative trait loci). In contrast, female MWF rats only develop a slight increase in UAE, while the role of genetic factors for this phenotype is unknown. In the present study, we show that, compared with resistant SHRs (spontaneously hypertensive rats), both male and female MWF rats develop a significant increase in UAE at 24 weeks of age (P<0.0001), although blood pressures were lower compared with SHRs (P<0.0001). UAE was significantly higher in male (7-fold) compared with female MWF rats (162.6+/-15.9 compared with 24.0+/-5.5 mg/24 h respectively; P<0.0001), and only male MWF rats developed significant glomerulosclerosis and tubulointerstitial damage in the kidney (P<0.0001). To test the role of genetic factors in the development of low grade albuminuria in female MWF rats, we analysed the role of a major UAE QTL on rat chromosome 6. To this end, we analysed a consomic MWF-6(SHR) strain in which chromosome 6 from SHRs was introgressed into the MWF rat background. Time course analysis of UAE in females indicated that the small increase in UAE in MWF rats was fully suppressed by exchange of rat chromosome 6. Thus, taken together with previous studies in males, we show that RNO6 protects against the increase in albuminuria with age in both female and male MWF rats.
Schulz
Angela
A
Institut für Klinische Pharmakologie und Toxikologie, Charité Centrum für Thearapieforschung, Charité-Universitätsmedizin Berlin, Berlin, Germany.
Schlesener
Maria
M
Weiss
Judith
J
Hänsch
Jonna
J
Wendt
Norbert
N
Kossmehl
Peter
P
Grimm
Daniela
D
Vetter
Roland
R
Kreutz
Reinhold
R
D000375:Aging; D000419:Albuminuria / Q000235:genetics* / Q000473:pathology; D000818:Animals; D020296:Animals, Congenic; D033481:Chromosomes, Mammalian; D005260:Female; D007668:Kidney / Q000473:pathology; D007674:Kidney Diseases / Q000235:genetics / Q000473:pathology; D008297:Male; D020412:Multifactorial Inheritance; D040641:Quantitative Trait Loci; D019655:Quantitative Trait, Heritable; D051381:Rats; D011918:Rats, Inbred SHR; D011919:Rats, Inbred Strains; D012727:Sex Characteristics