Carvajal de la FV, López MA, Martínez BJ, Barrón VC, Loredo OJC

Language: English/Spanish
References: 30
Page: 147-153
PDF size: 596.70 Kb.

ABSTRACT

"Meconium aspiration syndrome" is an important clinic-pathologic condition in human medicine, but its significance in veterinary medicine remains unknown. A recent study in calves with aspiration of keratin and amniotic fluid showed that inflammation in the lungs was only mild, in spite of the fact, that keratin is a highly pro-inflammatory substance. Based on the results of this study, the authors speculated that an anti-inflammatory substance may be present in the amniotic fluid. The purpose of this study was to determine whether the amniotic fluid has an anti-inflammatory effect in lungs of rats. Thirty eight Wistar rats with a mean weight of 177 g were divided into five groups. The rats were intratracheally inoculated with a constant volume of 0.5 ml of fluid containing 2.5 mg of silica, but with variable concentrations of amniotic fluid and saline solutions (0,0.125, 0.25, 0.375 or 0.5 ml). Rats were euthanised at 72 hours postinoculation under halothane anesthesia. The number of bronchoalveolar cells per ml and percentage of neutrophils and alveolar macrophages determined by bronchoalveolar lavage was used as a measurable indicator of pulmonary inflammation. Inoculation with amniotic fluid and silica induced a significant influx of nucleated cells and neutrophils (P‹0.01) in bronchoalveolar lavage fluid of inoculated animals versus the control. The increase of nucleated cells and neutrophils was related with the volume of amniotic fluid inoculated. It was concluded that the amniotic fluid did not induce any antiinflammatory effect in the lungs of rats inoculated with silica.

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