title: Upregulation of the L-type Calcium Channel in Renin-Positive Smooth Muscle Cells of Arterioles in the Kidneys of Rats with Streptozotocin-Induced Diabetes.
abstract: OBJECTIVE
  To estimate the number of L-type calcium (Ca2+) channels in the afferent and efferent arteriolar renin-positive and renin-negative smooth muscle cells and endothelial cells of the kidney arterioles in order to seek a relationship between the cell functions and the number of ion channels in the cell membranes.
  
  
  METHODS
  In diabetes the main source of renin/prorenin is the tubules, while the renin granulation of the afferent arterioles is increased relative to the normal. The release of renin is related to the Ca2+ levels of the intracellular and extracellular spaces of the afferent arterioles. The L-type calcium channel blockers have a stimulatory effect on the renin system. The immunohistochemical signal of the antibody against the L-type Ca2+ channels was estimated stereologically.
  
  
  RESULTS
  In the diabetic kidney the relative number of L-type Ca2+ channels on the surface of the renin-positive cells of the afferent arterioles was significantly increased. In the normal kidney there was a difference in the relative number of L-type Ca2+ channels on the surface of the endothelial cells between the renin-positive and renin-negative profiles of the afferent arterioles.
  
  
  CONCLUSIONS
  The increment in the number of Ca2+ channels on the renin-positive cell surface in the diabetic kidney could be related to the high renin granularity of the afferent arterioles. In the normal kidney the differences in the number of L-type Ca2+ channels on the endothelial cell surface may play a role in the higher permeability of the renin-positive part of the afferent arterioles.
authors.forename: Zsolt
authors.initials: Z
authors.lastname: Razga
authors.forename: Gabor
authors.initials: G
authors.lastname: Kovacs
authors.forename: Nikolett
authors.initials: N
authors.lastname: Bódi
authors.forename: Petra
authors.initials: P
authors.lastname: Talapka
mesh_terms: D000818:Animals; D001160:Arterioles / Q000378:metabolism* / Q000648:ultrastructure; D020746:Calcium Channels, L-Type / Q000096:biosynthesis*; D003921:Diabetes Mellitus, Experimental / Q000378:metabolism*; D042783:Endothelial Cells / Q000378:metabolism / Q000648:ultrastructure; D007150:Immunohistochemistry; D007668:Kidney / Q000378:metabolism* / Q000648:ultrastructure; D046529:Microscopy, Electron, Transmission; D032389:Myocytes, Smooth Muscle / Q000378:metabolism* / Q000648:ultrastructure; D051381:Rats; D012083:Renin / Q000378:metabolism; D015854:Up-Regulation
chemical_list: D020746:Calcium Channels, L-Type; D012083:Renin