title: Inflammatory process induced by carrageenan in adjacent tissue triggers the acute inflammation in deep digital flexor tendon of rats.
abstract: Tendinopathy is a pathology found mainly in the rotator cuff, patellar, Achilles and flexor tendons. Tendinopathy is a significant impediment to performance in athletes and in workers in the labor market. Some studies have indicated that inflammation in adjacent tissues may affect the rotator cuff and Achilles tendon. In this study alterations were verified in the extracellular matrix (ECM) of the deep digital flexor tendon after two periods (12 and 24 hr) of induction inflammation in rat paw. Wistar rats were divided into three groups: those that received injection of 1% carrageenan; those that received 0.9% NaCl; and those that received no application. The tendon was divided into distal (d), proximal (p), and intermediate (i) regions. Biochemical analyses were performed and included non-collagenous proteins (NCP), glycosaminoglycans (GAGs), hydroxyproline (HoPro) and metalloproteinases 2 and 9. Tissue sections were stained with toluidine blue, hematoxylin-eosin, and Ponceau SS and observed under polarization microscopy. Remarkable results were detected that included the presence of MMP-9, degradation of NCP and GAG and the presence of cellular infiltrate closer to digits in d region. The different concentrations of HoPro, as well as alterations in the organization of the collagen fibers showed the collagenous matrix undergoing some alterations. The results indicated that the induced inflammation in rat paw exhibited characteristics similar to the typical acute inflammatory process observed in tendons.
authors.affiliation: Department of Structural and Functional Biology, Institute of Biology, UNICAMP, SP, Brazil.
authors.forename: Cristiano Pedrozo
authors.initials: CP
authors.lastname: Vieira
authors.forename: Andrea Aparecida
authors.initials: AA
authors.lastname: De Aro
authors.forename: Flávia
authors.initials: F
authors.lastname: Da Ré Guerra
authors.forename: Letícia Prado
authors.initials: LP
authors.lastname: De Oliveira
authors.forename: Marcos Dos Santos
authors.initials: Mdos S
authors.lastname: De Almeida
authors.forename: Edson Rosa
authors.initials: ER
authors.lastname: Pimentel
mesh_terms: D000818:Animals; D002351:Carrageenan / Q000009:adverse effects*; D004195:Disease Models, Animal; D005109:Extracellular Matrix / Q000378:metabolism / Q000473:pathology; D006025:Glycosaminoglycans / Q000378:metabolism; D006909:Hydroxyproline / Q000378:metabolism; D007249:Inflammation / Q000139:chemically induced* / Q000473:pathology / Q000503:physiopathology*; D008297:Male; D020780:Matrix Metalloproteinase 9 / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D052256:Tendinopathy / Q000139:chemically induced* / Q000473:pathology / Q000503:physiopathology*; D013997:Time Factors
chemical_list: D006025:Glycosaminoglycans; D002351:Carrageenan; D020780:Matrix Metalloproteinase 9; D006909:Hydroxyproline
keywords: acute inflammation; collagen; extracellular matrix; injury; tendinopathy