title: Acute cardiopulmonary alterations induced by fine particulate matter of São Paulo, Brazil.
abstract: The mechanisms involved in the association between air pollution and increased cardiovascular morbidity are not fully understood. The objective of this study was to test the hypothesis that fine particulate matter (PM(2.5)) induces systemic inflammation and vasoconstriction of small arteries in the lung and heart of rats. Thirty-eight healthy Wistar rats were anesthetized, intubated, and submitted to the instillation of 1 ml of distilled water diluted in the following solution: blank filter, 100 microg and 500 microg of PM(2.5). PM(2.5) was collected in glass fiber filters with a high-volume sampler. The animals were sacrificed 24 h after instillation when blood, heart, and lung samples were collected for morphological and wet-to-dry weight ratio analysis. PM(2.5) consisted of the following elements: sulphur, arsenic, bromine, chlorine, cobalt, iron, lanthanum, manganese, antimony, scandium, and thorium. Total reticulocytes significantly increased at both PM(2.5) doses (p < 0.05) while hematocrit levels increased in the 500 microg group (p < 0.05). Quantification of segmented neutrophils and fibrinogen levels showed a significant decrease, while lymphocytes counting increased with 100 microg of PM(2.5) (p < 0.05). A significant dose-dependent decrease of intra-acinar pulmonary arteriole lumen/wall ratio (L/W) was observed in PM groups (p < 0.001). Peribronchiolar arterioles L/W showed a significant decrease in the 500 microg group (p < 0.001). A significant increase in heart wet-to-dry weight ratio was observed in the 500 microg group (p < 0.001). In conclusion, fine environment particles in the city of São Paulo promote pulmonary and cardiac histological alterations. Pulmonary vasculature was markedly affected by particle instillation, resulting in significant vasoconstriction in healthy rats.
authors.affiliation: Department of Pathology, School of Medicine, University of São Paulo, São Paulo, Brazil. dohelena@usp.br
authors.forename: Dolores Helena Rodriguez Ferreira
authors.initials: DH
authors.lastname: Rivero
authors.forename: Sandra Regina Castro
authors.initials: SR
authors.lastname: Soares
authors.forename: Geraldo
authors.initials: G
authors.lastname: Lorenzi-Filho
authors.forename: Mitiko
authors.initials: M
authors.lastname: Saiki
authors.forename: John J
authors.initials: JJ
authors.lastname: Godleski
authors.forename: Leila
authors.initials: L
authors.lastname: Antonangelo
authors.forename: Marisa
authors.initials: M
authors.lastname: Dolhnikoff
authors.forename: Paulo Hilário Nascimento
authors.initials: PH
authors.lastname: Saldiva
mesh_terms: D000280:Administration, Inhalation; D000393:Air Pollutants / Q000633:toxicity*; D000818:Animals; D001158:Arteries / Q000473:pathology; D001835:Body Weight / Q000187:drug effects; D001938:Brazil; D006321:Heart / Q000187:drug effects*; D007249:Inflammation / Q000139:chemically induced / Q000473:pathology; D008168:Lung / Q000187:drug effects* / Q000473:pathology; D008297:Male; D009206:Myocardium / Q000473:pathology; D009929:Organ Size / Q000187:drug effects; D010316:Particle Size; D051381:Rats; D017208:Rats, Wistar
chemical_list: D000393:Air Pollutants