title: Structural changes in the renal vasculature in streptozotocin-induced diabetic rats without hypertension.
abstract: OBJECTIVE
  We evaluated in diabetic-streptozotocin rats (STZR) the structural changes of glomeruli, preglomerular vessels, glomerular tuft and renal parenchyma in order to determine the degree of renal injury and the presence of remodeling in afferent arterioles developed by diabetes without overimposed hypertension.
  
  
  METHODS
  Renal mass index and histological score (glomerular number, density, tubular lesions and degree of arteriosclerosis) were estimated. In afferent arterioles the ratio of wall thickness/lumen was obtained by stereological methods.
  
  
  RESULTS
  STZR developed diabetes without hypertension; renal mass index increased and matched changes in glomeruli (decrease of capillary number and enlargement of mesangium and basement capillary membrane). Both glomerular number and density as well as afferent arteriole number were diminished. Degenerative changes in both proximal (glycogenic and hyaline degeneration) and distal tubules (hyaline casts) were also observed. At variance with preglomerular vessels, the efferent arterioles only presented initial arteriosclerosis. Finally, the stereological study of afferent arterioles showed a significantly lower arteriolar lumen area and arteriolar wall thickness in STZR, resulting in a remodeling without modification of wall/lumen ratio.
  
  
  CONCLUSIONS
  Diabetes, uncomplicated by hypertension, is associated with (1) a reduction in glomerular number; (2) degeneration in parenchyma and renal tubules, and (3) a specific pattern of remodeling in preglomerular vessels different from that induced by hypertension. Although this work demonstrated that these changes are not triggered by hypertension, further investigations are required in order to determine which mediators are involved in diabetic-vascular renal dysfunction.
authors.affiliation: Department of Physiology, INSIBIO, Universidad Nacional de Tucumán, Tucumán, Argentina.
authors.forename: Claudio M Joo
authors.initials: CM
authors.lastname: Turoni
authors.forename: Héctor A
authors.initials: HA
authors.lastname: Reynoso
authors.forename: Rodrigo O
authors.initials: RO
authors.lastname: Marañón
authors.forename: Alfredo
authors.initials: A
authors.lastname: Coviello
authors.forename: María
authors.initials: M
authors.lastname: Peral de Bruno
mesh_terms: D000818:Animals; D050197:Atherosclerosis / Q000209:etiology / Q000473:pathology*; D003921:Diabetes Mellitus, Experimental / Q000139:chemically induced / Q000150:complications / Q000473:pathology*; D003928:Diabetic Nephropathies / Q000473:pathology*; D006973:Hypertension / Q000473:pathology; D007668:Kidney / Q000098:blood supply* / Q000187:drug effects / Q000473:pathology*; D008297:Male; D008833:Microcirculation / Q000187:drug effects / Q000473:pathology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013311:Streptozocin
chemical_list: D013311:Streptozocin