5/6 Nephrectomy Model
As a preclinical Contract Research Organization (CRO), we provide validated surgical 5/6 nephrectomy models to support mechanism-of-action, proof-of-concept, and efficacy studies for chronic kidney disease (CKD) drug development. Our services are designed for scientific rigor, translational relevance, and regulatory-ready data generation.
The Gold-Standard Surgical Model for Progressive Renal Failure
The 5/6 nephrectomy (5/6 Nx) model remains the most widely validated and translational preclinical platform for studying progressive chronic kidney disease (CKD), renal fibrosis, and cardiorenal syndrome. By surgically ablating five-sixths of total renal mass, this model recapitulates the hemodynamic, metabolic, and structural pathophysiology of human CKD with high fidelity — making it indispensable for efficacy testing of novel renoprotective, anti-fibrotic, and cardiometabolic therapeutics.
Surgical Induction Methods
Two-Step 5/6 Nephrectomy
1. Phase I: Unilateral nephrectomy (right kidney removal) via flank incision under isoflurane anesthesia.
2. Recovery Period: 7-day recovery to ensure hemodynamic stabilization.
3. Phase II: Contralateral flank incision to surgically excise the upper and lower poles of the left kidney (2/3 ablation), leaving approximately 1/6 of total renal mass.
Advantages: Improved perioperative survival, greater hemodynamic stability, reduced acute inflammatory response, and consistent progressive CKD phenotype.
Study Design & Assessment Endpoints
Primary Renal Function Endpoints
| Parameter | Method |
| Serum Creatinine (SCr) | Automated biochemistry analyzer |
| Blood Urea Nitrogen (BUN) | Automated biochemistry analyzer |
| 24h Urinary Protein / Albumin-to-Creatinine Ratio (ACR) | ELISA or automated analyzer |
Histopathological & Molecular Endpoints
| Parameter | Method |
| Glomerulosclerosis | PAS staining, H&E; semi-quantitative scoring |
| Tubulointerstitial Fibrosis | Masson's Trichrome, Sirius Red; morphometric quantification |
| Myofibroblast Activation | α-SMA IHC / Western blot |
| TGF-β Signaling | TGF-β1 IHC / qPCR |
| Collagen Expression | Collagen I, III IHC / Western blot / qPCR |
Therapeutic Applications
The 5/6 nephrectomy model supports preclinical evaluation across diverse therapeutic modalities:
Renin-Angiotensin-Aldosterone System (RAAS) Inhibitors
ACE inhibitors, ARBs, mineralocorticoid receptor antagonists
Anti-Fibrotic Agents
TGF-β pathway inhibitors, anti-CTGF antibodies, pirfenidone analogs
Anti-Hypertensive Therapeutics
Endothelin receptor antagonists, calcium channel blockers, SGLT2 inhibitors
Antioxidant & Nrf2 Activators
Bardoxolone methyl analogs, curcumin derivatives, NADPH oxidase inhibitors
CKD-Mineral Bone Disorder (CKD-MBD) Therapies
Phosphate binders, calcimimetics, FGF23-neutralizing antibodies
Novel Biologics & Gene Therapies
siRNA, antisense oligonucleotides, cell-based therapies
Why Partner With Us?
Translational Rigor
- Strain-matched controls and power-calculated group sizes based on historical effect-size data
- Blinded histopathological scoring by certified veterinary pathologists using standardized scoring systems (e.g., Banff-like criteria adapted for rodents)
Customization & Flexibility
- Dietary modifications: High-phosphate, low-protein, or adenine-supplemented diets to accelerate vascular calcification or secondary hyperparathyroidism
- Combination models: 5/6 Nx + UUO, 5/6 Nx + diabetes (STZ), or 5/6 Nx + uninephrectomy in aged animals
Integrated Data Package
- Renal function panels: SCr, BUN
- Urine metabolomics & proteomics (optional add-on)
- Histopathology report: H&E, PAS, Masson Trichrome, Sirius Red, and IHC
- Statistical analysis with mixed-effects models for repeated measures
Representative Data & Case Study
Fig. 1. Kidney morphology. (a) Renal interstitial fibrosis, (b) typical photomicrographs of the kidneys stained with sirius red for interstitial fibrosis, (c) glomerular size, and (d) typical photomicrographs of the kidneys stained with sirius red for glomerular hypertrophy (Tsuprykov, Oleg, et al., 2016).
FAQ
Which species is best for testing RAAS inhibitors?
Rats, particularly Sprague-Dawley (SD) rats, are commonly used in 5/6 nephrectomy studies to evaluate RAAS-targeting therapies, including ACE inhibitors and angiotensin receptor blockers (ARBs). The selection of animal strain and experimental conditions can be tailored to specific research objective
How do you ensure surgical consistency across studies?
All surgeries are performed by the same team of experienced surgeons using standardized SOPs. We track perioperative mortality, surgical time, and postoperative weight recovery as quality control metrics. Batch-to-batch consistency is monitored via positive control groups.
Request a Study Proposal
Contact our scientific team to discuss your specific therapeutic hypothesis, target engagement strategy, and biomarker requirements. We provide no-obligation study design consultations and can deliver a customized protocol and quotation within 24 hours.