Efeito da betametasona e do diclofenaco sódico na concentração sérica e tecidual da amoxicilina. Estudo in vivo em ratos

CAPES - COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL E NÍVEL SUPERIORAntimicrobial agents in combination with anti-inflammatory drugs have been usually prescribed in both Medicine and Dentistry. However, few scientific reports support this clinical practice. The aim of this study was to evaluate the effect of betamethasone and diclofenac sodium on serum and tissue concentration of amoxicillin in rats. Four polyurethane sponges were implanted in the back skin of 48 rats. After seven days the animals were divided into 6 groups (n=8). Group 1: amoxicillin (25 mg/kg); G2: diclofenac sodium (2.5 mg/kg); G3: betamethasone (0.1 mg/kg); G4: diclofenac sodium and amoxicillin; G5: betamethasone and amoxicillin; and G6: 0.9% sodium chloride solution (1.0 mL - control group). All drugs were administered in a single dose. After 90 minutes, the granulomatous tissues of each animal were surgically removed and weighed. Blood was collected from cervical plexus, centrifuged and 10microL of serum was placed on paper discs. In order to estimate amoxicillin concentration, serum and granulomatous tissues were separately submitted to microbiological assay, which used 10(8)cfu/mL of Staphylococcus aureus ATCC 25923 (penicillin-susceptible strain). After incubation (18 hours, 37 degrees C) the inhibition zones were measured and compared to a regression curve. No inhibition zones were observed for groups 2, 3 and 6. Tissue and serum concentrations of both G1 (4.14microg/g and 2.06microg/mL, respectively) and G5 (3.87microg/g and 1.70microg/mL, respectively) showed statistically significant differences (Kruskal-Wallis, p0.05). Considering single doses, betamethasone did not interfere with amoxicillin levels but diclofenac sodium reduced both tissue and serum levels of amoxicillin in rats.Antimicrobial agents in combination with anti-inflammatory drugs have been usually prescribed in both Medicine and Dentistry. However, few scientific reports support this clinical practice. The aim of this study was to evaluate the effect of betamethasone and diclofenac sodium on serum and tissue concentration of amoxicillin in rats. Four polyurethane sponges were implanted in the back skin of 48 rats. After seven days the animals were divided into 6 groups (n=8). Group 1: amoxicillin (25 mg/kg); G2: diclofenac sodium (2.5 mg/kg); G3: betamethasone (0.1 mg/kg); G4: diclofenac sodium and amoxicillin; G5: betamethasone and amoxicillin; and G6: 0.9% sodium chloride solution (1.0 mL - control group). All drugs were administered in a single dose. After 90 minutes, the granulomatous tissues of each animal were surgically removed and weighed. Blood was collected from cervical plexus, centrifuged and 10µL of serum was placed on paper discs. In order to estimate amoxicillin concentration, serum and granulomatous tissues were separately submitted to microbiological assay, which used 108cfu/mL of Staphylococcus aureus ATCC 25923 (penicillin-susceptible strain). After incubation (18 hours, 37ºC) the inhibition zones were measured and compared to a regression curve. No inhibition zones were observed for groups 2, 3 and 6. Tissue and serum concentrations of both G1 (4.14µg/g and 2.06µg/mL, respectively) and G5 (3.87µg/g and 1.70µg/mL, respectively) showed statistically significant differences (Kruskal-Wallis, p0.05). Considering single doses, betamethasone did not interfere with amoxicillin levels but diclofenac sodium reduced both tissue and serum levels of amoxicillin in rats145319323CAPES - COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL E NÍVEL SUPERIORCAPES - COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL E NÍVEL SUPERIORsem informaçãoA prescrição de antimicrobianos associados a antiinflamatórios é uma prática comum em odontologia, embora na maioria das vezes não haja justificativa para tal conduta. O objetivo deste trabalho foi avaliar, em um estudo in vivo em ratos, os efeitos da betametasona e do diclofenaco sódico nas concentrações sérica e tecidual da amoxicilina. Foram utilizados 48 ratos Wistar machos (6 grupos, n=8), com idade de 60 dias. Esponjas de PVC (policlorovinil) foram implantadas em quatro pontos no dorso de cada animal. Após sete dias, foram administrados por via intragástrica ou intramuscular: Grupo 1: amoxicilina (25 mg/kg); G2: diclofenaco sódico (2,5 mg/kg/i.m.); G3: betametasona (0,1 mg/kg/i.m.); G4: diclofenaco sódico e amoxicilina; G5: betametasona e amoxicilina; e G6: solução de cloreto de sódio a 0,9% (1,0 mL – grupo controle). Após 90 minutos, foram colhidos 2 tecidos granulomatosos e amostras séricas de cada animal e colocados em meios de cultura inoculados com 108 ufc/mL de Staphylococcus aureus ATCC 25923. Os halos de inibição foram medidos após 18 horas de incubação (37ºC), e através do teste microbiológico foram obtidas as concentrações séricas e teciduais da amoxicilina. Não foram observados halos de inibição para os grupos 2, 3 e 6. As concentrações séricas e teciduais de G1 (4,14µg/g e 2,06µg/mL, respectivamente) e G5 (3,87µg/g e 1,70µg/mL, respectivamente) demonstraram diferenças estatisticamente significantes (Kruskal-Wallis, p0,05). Considerando uma dose única, a betametasona não interferiu nas concentrações sérica e tecidual de amoxicilina, enquanto o diclofenaco sódico reduziu as concentrações sérica e tecidual de amoxicilina em rato