Serial determination of glomerular filtration rate in conscious mice using FITC-inulin clearance.
Two nonradioactive methods for determining glomerular filtration rate (GFR) in conscious mice using FITC-labeled inulin (FITC-inulin) were evaluated. The first method measured GFR using clearance kinetics of plasma FITC-inulin after a single bolus injection. Based on a two-compartment model, estimated GFR was 236.69 +/- 16.55 and 140.20 +/- 22.27 microl/min in male and female C57BL/6J mice, respectively. Total or (5/6) nephrectomy reduced inulin clearance to 0 or 32.80 +/- 9.32 microl/min, respectively. Conversely, diabetes mellitus induced by streptozotocin was associated with increased GFR. The other approach measured urinary inulin clearance using intraperitoneal microosmotic pumps to deliver FITC-inulin and metabolic cages to collect timed urine samples. This approach yielded similar GFR values of 211.11 +/- 26.56 and 157.36 +/- 20.02 microl/min in male and female mice, respectively. These studies demonstrate the feasibility of repeated nonisotopic measurement of inulin clearance in conscious mice.
Department of Medicine, Vanderbilt University, Nashville, TN 37212, USA. zhonghua.qi@vanderbilt.edu
Zhonghua
Z
Qi
Irene
I
Whitt
Amit
A
Mehta
Jianping
J
Jin
Min
M
Zhao
Raymond C
RC
Harris
Agnes B
AB
Fogo
Matthew D
MD
Breyer
D000818:Animals; D003243:Consciousness; D003921:Diabetes Mellitus, Experimental / Q000652:urine; D005260:Female; D016650:Fluorescein-5-isothiocyanate / Q000008:administration & dosage; D005456:Fluorescent Dyes / Q000008:administration & dosage; D005919:Glomerular Filtration Rate; D007267:Injections; D007444:Inulin / Q000008:administration & dosage / Q000097:blood / Q000652:urine*; D007677:Kidney Function Tests / Q000379:methods; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D009392:Nephrectomy
D005456:Fluorescent Dyes; D007444:Inulin; D016650:Fluorescein-5-isothiocyanate