Creating experimental models for obtaining stem cells from adipose tissue is necessary to elucidate their peculiar features. Objective: This study proposed a reliable reproducible and consistent experimental model for obtaining mesenchymal stem cells from adipose tissue. Material and Method: Lines of New Zealand rabbits, Wistar rats and CaviaPorcellus guinea pigs (4 animals per species) were used. Fatty tissue mesenchymal stem cells were removed from dorsal, epididymal and inguinal regions. Percentage viable cells and percentage cells expanded and submitted to chondrogenic differentiation were compared by animal species and collection site. Results: Chondrogenic differentiation occurred in a similar manner across all samples, independently of animal species or collection site. Among samples assessed, the inguinal region of rats yielded the highest percentage of viable and expanded cells. Conclusion: A reliable, reproducible and consistent model for obtaining mesenchymal stem cells was produced. Of the several variables analysed, the best results were obtained from the inguinal region of the rat.

BackgroundMelanoma is the skin cancer with highest mortality potential, representing about 4% of all skin tumors. This tumor is among the causes of Membranous Nephropathy. This is a disease characterized by diffuse thickening of the glomerular capillary wall due to the accumulation of electrodens immunglobulin depositis along the subepithelial side of the basement membrane. The glomerular wall becomes defective, which in the long term may lead to loss of renal function [1]. In addition to the deposition of immunoglobulin complexes, the abundant secretion of melanin by this type of tumor leads to renal failure. Notably, the clinical progression of patients with metastatic melanoma are renal insufficiency, with a sequence of infections due to immunological involvement, ascites, hypertension and subsequent hypotension associated with sepsis. Melanoma, despite having characteristics of differentiated melanocyte as the secretion of melanin, is a tumor with a high degree of aplasia. The endocrine action and abundant secretion of melanin promotes a break in homeostasis and the kidneys are commonly affected first.In a case report, clinicians described a patient who presented Renal Failure due to deposition of immuno-complexes without apparent cause, after six months the diagnosis of metastatic melanoma was described, the first manifestation being nephropathy [2]. In patients and melanoma-bearing mice experimental models the observation of melanin deposits is common over the abdominal cavity.