ABSTRACT
PURPOSE: To evaluate the effect of propranolol on capsular architecture around silicone implants by measuring the inflammation, capsular thickness, and collagen fiber density, using a guinea pig experimental model. METHODS: Thirty six adult male guinea pigs randomly divided into two groups (n=18) were used. Each one received a silicone implant with textured-surface. The capsular tissue around implants from untreated or treated animals with the beta-adrenoceptor antagonist propranolol (10 mg/kg, dissolved in daily water) were analyzed for inflammation by histological scoring, capsular thickness by computerized histometry, and collagen fibers type I and Type III density by picrosirius polarization at different time points (7, 14 or 21 days after silicone implantation). RESULTS: Propranolol treatment reduced inflammation and impaired capsular thickness and delayed collagen maturation around the textured implant. CONCLUSION: Propranolol reduces the risk of developing capsular contracture around silicone implants with textured surface. .
Subject(s)
Animals , Guinea Pigs , Humans , Male , Adrenergic beta-Antagonists/pharmacology , Implant Capsular Contracture/prevention & control , Propranolol/pharmacology , Silicone Gels/adverse effects , Adrenergic beta-Antagonists/therapeutic use , Breast Implants/adverse effects , Collagen Type I/analysis , Collagen Type I/drug effects , Collagen Type III/analysis , Collagen Type III/drug effects , Disease Models, Animal , Implant Capsular Contracture/pathology , Implants, Experimental/adverse effects , Propranolol/therapeutic use , Random Allocation , Reproducibility of Results , Subcutaneous Tissue/drug effects , Subcutaneous Tissue/pathology , Time Factors , Treatment OutcomeABSTRACT
PURPOSE: To evaluate the effect of zafirlukast on capsular contracture around silicone implants by measuring the pressure within the implant, using a rat experimental model. METHODS: Forty adult female Wistar rats were used. Each one received two silicone implants, one with smooth-surface and the other with textured-surface. They were randomly divided into four groups (n=10). The rats of control group I were sacrificed after the implants. The remaining animals were subjected to a daily regimen of intra-peritoneal injection for a period of 90 days and they were distributed as follows: control group II received 0.9 percent physiological saline solution; experimental group I received zafirlukast 1.25 mg/kg; and experimental group II received zafirlukast 5 mg/kg. The measurement of intra-implant pressure of control group I was determined on the surgery day and in other groups on the ninetieth day, after being sacrificed. RESULTS: In the evaluation of textured implants there was an increase of internal pressure in the control group II, and there was no increase in the experimental groups. Compared to the controls there were not significant differences in smooth implants. CONCLUSION: Zafirlukast reduced the risk of developing capsular contracture around silicone implants with textured surface.
OBJETIVO: Avaliar o efeito do zafirlukast na contratura capsular ao redor de implantes de silicone, através da aferição da pressão intra-implante, utilizando-se um modelo experimental de ratos. MÉTODOS: Quarenta ratos fêmeas Wistar foram utilizados. Cada um recebeu dois implantes de silicone, sendo um com superfície lisa e outro texturizada. Foram divididos aleatoriamente em quatro grupos (n=10). Os ratos do grupo controle I foram sacrificados após o implante. O restante dos animais foi submetido a um regime diário de injeção intraperitoneal por um período de 90 dias e foram distribuídos: grupo controle II recebeu solução salina fisiológica 0,9 por cento, grupo experimental I recebeu zafirlukast 1,25 mg/kg, e grupo experimental II recebeu zafirlukast 5 mg/kg. O grupo controle II recebeu solução salina; grupo experimental I, 1,25 mg/kg/dia de zafirlukast; grupo experimental II, 5mg/kg/dia de zafirlukast. A aferição da pressão intra-implante do grupo controle I foi averiguada no dia do ato operatório, e nos outros grupos no nonagésimo dia, após serem sacrificados. RESULTADOS: Na avaliação dos implantes texturizados houve aumento da pressão interna no grupo controle II e, não se observou aumento nos grupos experimentais. Na comparação com os controles não foram observadas diferenças significativas nos implantes lisos. CONCLUSÃO: O Zafirlukast reduziu o risco de desenvolver contratura capsular em torno de implantes de silicone com superfície texturizada.