title: Histomorphometric evaluation of the small coronary arteries in rats exposed to industrial noise.
abstract: Morphological changes induced by industrial noise (IN) have been experimentally observed in several organs. Histological observations of the coronary arteries showed prominent perivascular tissue and fibrosis among IN-exposed rats. The effects on the small arteries are unknown.
  
  
  OBJECTIVE
  To evaluate the histomorphometric changes induced by IN on rat heart small arteries.
  
  
  METHODS
  Twenty Wistar rats exposed to IN during a maximum period of seven months and 20 age-matched controls were studied. Hearts were transversely sectioned from ventricular apex to atria and a mid-ventricular fragment was selected for analysis. The histological images were obtained with an optical microscope using 400× magnifications. A total of 634 arterial vessels (298 IN-exposed and 336 controls) were selected. The mean lumen-to-vessel wall (L/W) and mean vessel wall-to-perivascular tissue (W/P) ratios were calculated using image J software.
  
  
  RESULTS
  There were no differences between exposed and control animals in their L/W ratios (p=0.687) and time variations in this ratio were non-significant (p=0.110). In contrast, exposed animals showed lower W/P ratios than control animals (p<0.001), with significant time variations (p=0.004).
  
  
  CONCLUSIONS
  Industrial noise induced an increase in the perivascular tissue of rat small coronary arteries, with significant development of periarterial fibrosis.
authors.affiliation: Center for Interdisciplinary Research Egas Moniz (CIIEM), Health Sciences Institute, 2829-511 Monte de Caparica, Portugal. alousinha@gmail.com.
authors.forename: Ana
authors.initials: A
authors.lastname: Lousinha
authors.affiliation: Center for Interdisciplinary Research Egas Moniz (CIIEM), Health Sciences Institute, 2829-511 Monte de Caparica, Portugal. ejpantunes@sapo.pt.
authors.forename: Eduardo
authors.initials: E
authors.lastname: Antunes
authors.affiliation: Center for Interdisciplinary Research Egas Moniz (CIIEM), Health Sciences Institute, 2829-511 Monte de Caparica, Portugal. gborrecho@gmail.com.
authors.forename: Gonçalo
authors.initials: G
authors.lastname: Borrecho
authors.affiliation: Department of Anatomy, Abel Salazar Biomedical Sciences Institute, University of Porto, 4050-313 Porto, Portugal. mjoliveira@icbas.up.pt.
authors.forename: Maria João
authors.initials: MJ
authors.lastname: Oliveira
authors.affiliation: Center for Interdisciplinary Research Egas Moniz (CIIEM), Health Sciences Institute, 2829-511 Monte de Caparica, Portugal. jaabrito@netcabo.pt.
authors.forename: José
authors.initials: J
authors.lastname: Brito
authors.affiliation: Center for Interdisciplinary Research Egas Moniz (CIIEM), Health Sciences Institute, 2829-511 Monte de Caparica, Portugal. jsantos@egasmoniz.edu.pt.
authors.forename: José Martins
authors.initials: JM
authors.lastname: dos Santos
mesh_terms: D000818:Animals; D003331:Coronary Vessels / Q000473:pathology / Q000528:radiation effects*; D005355:Fibrosis / Q000209:etiology; D009623:Noise, Occupational / Q000009:adverse effects*; D051381:Rats; D017208:Rats, Wistar