title: Nuclear size measurements in collecting tubules of the rat kidney in establishing the effect of hypokinesia on the kidney morphology.
abstract: BACKGROUND
  Hypokinesia (reduced motor activity) induces significant tissue morphological changes, however, it is not known if hypokinesia (HK) could contribute to morphological changes in the kidney. Measuring the nuclear size in the inner medullary collecting ducts on the kidney of rats the aim of this investigation was to disclose kidney morphological changes during prolonged HK.
  
  
  METHODS
  Studies were done on 192 13-week-old male rats (370 to 390 g) during 15 days pre-HK period and 90 days HK period. Rats were equally divided into 2 groups: vivarium control rats (VCR) and hypokinetic rats (HKR). All HKR were kept in small individual cages.
  
  
  RESULTS
  A significant (p<0.05) increase in size of collecting duct nuclei of the kidney, plasma aldosterone (PA), plasma and urinary Sodium (Na) and Potassium (K) and fluid loss, a significant (p<0.05) decrease of fluid intake, body weight and plasma antidiuretic hormone (ADH) observed in HKR when compared with their pre-HK values and the values in VCR. The measured parameters change insignificantly (p>0.05) in VCR when compared with their pre-HK values.
  
  
  CONCLUSIONS
  It was concluded that the nuclear size in the inner medullary collecting ducts of the kidney increases significantly during prolonged HK. The reason for this reaction remains unclear.
authors.affiliation: Kosmic Biology and Medicine Institute, Krasno Selo, Sofia, Bulgaria.
authors.forename: Y G
authors.initials: YG
authors.lastname: Zorbas
authors.forename: V B
authors.initials: VB
authors.lastname: Afonin
authors.forename: K P
authors.initials: KP
authors.lastname: Charapakhin
authors.forename: S D
authors.initials: SD
authors.lastname: Denogratov
mesh_terms: D000818:Animals; D002467:Cell Nucleus / Q000473:pathology*; D007674:Kidney Diseases / Q000473:pathology* / Q000503:physiopathology; D007685:Kidney Tubules, Collecting / Q000473:pathology* / Q000503:physiopathology; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley