Zinc deficiency during growth: influence on renal function and morphology.
This study was designed to investigate the effects of moderate zinc deficiency during growth on renal morphology and function in adult life. Weaned male Wistar rats were divided into two groups and fed either a moderately zinc-deficient diet (zinc: 8 mg/kg, n=12) or a control diet (zinc: 30 mg/kg, n=12) for 60 days. We evaluated: renal parameters, NADPH-diaphorase and nitric oxide synthase activity in kidney, renal morphology and apoptotic cells in renal cortex. Zinc-deficient rats showed a decrease in glomerular filtration rate and no changes in sodium and potassium urinary excretion. Zinc deficiency decreased NADPH diaphorase activity in glomeruli and tubular segment of nephrons, and reduced activity of nitric oxide synthase in the renal medulla and cortex, showing that zinc plays an important role in preservation of the renal nitric oxide system. A reduction in nephron number, glomerular capillary area and number of glomerular nuclei in cortical and juxtamedullary areas was observed in zinc deficient kidneys. Sirius red staining and immunostaining for alpha-smooth muscle-actin and collagen III showed no signs of fibrosis in the renal cortex and medulla. An increase in the number of apoptotic cells in distal tubules and cortical collecting ducts neighboring glomeruli and, to a lesser extent, in the glomeruli was observed in zinc deficient rats. The major finding of our study is the emergence of moderate zinc deficiency during growth as a potential nutritional factor related to abnormalities in renal morphology and function that facilitates the development of cardiovascular and renal diseases in adult life.
Tomat
Analía Lorena
AL
Cátedra de Fisiología, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, IQUIMEFA-CONICET, Junín 956, Piso 7, 1113 Ciudad Autónoma de Buenos Aires, Argentina.
Costa
María Angeles
MA
Girgulsky
Luciana Carolina
LC
Veiras
Luciana
L
Weisstaub
Adriana Ruth
AR
Inserra
Felipe
F
Balaszczuk
Ana María
AM
Arranz
Cristina Teresa
CT
D000818:Animals; D017209:Apoptosis; D015415:Biomarkers / Q000378:metabolism; D001794:Blood Pressure / Q000187:drug effects; D005919:Glomerular Filtration Rate; D007091:Image Processing, Computer-Assisted; D007124:Immunoenzyme Techniques; D020287:In Situ Nick-End Labeling; D007668:Kidney / Q000201:enzymology / Q000254:growth & development* / Q000473:pathology; D008297:Male; D009252:NADPH Dehydrogenase / Q000378:metabolism*; D019001:Nitric Oxide Synthase / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D015032:Zinc / Q000172:deficiency*
D015415:Biomarkers; D019001:Nitric Oxide Synthase; D009252:NADPH Dehydrogenase; D015032:Zinc