The effect of premedication with phenylbutazone on systemic hemodynamic and diuretic effects of furosemide was examined in 6 healthy, conscious, mares. Mares were instrumented for measurement of systemic hemodynamics, including cardiac output and pulmonary arterial, systemic arterial, and intracardiac pressures, and urine flow. Each of 3 treatments was administered in a randomized, blinded study; furosemide (1 mg/kg of body weight, IV) only, phenylbutazone (8.8 mg/kg PO, at 24 hours and 4.4 mg/kg IV, 30 minutes before furosemide) and furosemide, or 0.9% NaCl. Phenylbutazone administration significantly attenuated, but did not abolish, the diuretic effect of furosemide. Phenylbutazone completely inhibited the immediate effect of furosemide on cardiac output, stroke volume, total peripheral resistance, and right ventricular peak pressure. Premedication with phenylbutazone did not inhibit equally the diuretic and hemodynamic effects of furosemide, indicating that some of furosemide's hemodynamic effects are mediated by an extrarenal activity of furosemide.

No processo de cicatrização por segunda intenção de feridas cutâneas experimentalmente induzidas em equinos, avaliaram-se os efeitos da fenilbutazona e comparou-se a cicatrização entre as regiões torácica e lombar. Utilizaram-se dez equinos, dos quais se retirou fragmentos circulares de pele de dois centímetros de diâmetro das regiões lombares e torácicas direita e esquerda. Os equinos foram distribuídos em dois grupos, sendo o primeiro controle, recebendo água destilada a cada 12 horas, durante cinco dias. O outro grupo foi tratado com fenilbutazona (4,4 mg/kg) com o mesmo intervalo e período do grupo controle. As feridas foram tratadas diariamente com Líquido de Dakin, momentos quando se procederam as observações macroscópicas. A cada 72 horas procederam-se as mensurações das feridas. Para análise histológica realizou-se biópsias no sexto e décimo quinto dia. O tempo total de reparo das feridas no grupo tratado foi maior em aproximadamente 12 dias (37 dias para o grupo controle e 49 dias para o grupo tratado). Não se observou diferença significativa do tempo de cicatrização entre as feridas torácicas e lombares de um mesmo grupo. As avaliações macroscópicas e histopatológicas mostraram o efeito inibidor da fenilbutazona quando comparada com o grupo controle na cicatrização de feridas cutâneas por segunda intenção em equinos. | The purpose of this study was to investigate phenylbutazone effects on second intention wound healing, and to compare the healing process between the thoracic and lumbar areas. Ten horses were submitted to circular full-thickness wound produced on both sides of the thoracic and lumbar areas. Animals were gathered into two experimental groups, one receiving daily IV injections of phenylbutazone (4,4mg/kg) and the other (control group) distillated water for five days. All wounds were daily treated with local Dakin's solution. The wound contraction rates were determined by serial measurements each 72 hours. At the 6th and 15th post surgical days, biopsies were performed for histological analysis. Thoracic and lumbar wound contraction was decreased in the phenylbutazone group. The time to complete healing was significantly greater in phenylbutazone group (49 days) than in control group (37 days). There was no significant difference between thoracic and lumbar area in the same group. Gross and histopathology analysis showed the inhibitory effect of phenylbutazone on the second-intention wound healing when compared to the control group.