Experimentally induced sinusitis: the importance of vasomotor regulation

An acute pneumococcal maxillary sinusitis was induced in New Zealand white rabbits by unilateral obstruction of the sinus ostium and then injecting 10(8) Streptococcus pneumoniae into the sinus. After subjecting this bacterial strain to one animal passage, the bacteria were reisolated in nine of ten infected maxillary sinuses. All rabbits developed a unilateral purulent sinusitis, while a non-purulent sinusitis could be induced by occlusion only of the maxillary ostium. By using a non-diffusable tracer, microspheres labelled with Sn113, blood flow measurements were performed on these sinuses. These studies showed that the blood flow of the infected sinuses was significantly higher than on the control side. However, in chronic sinusitis (with a blocked ostium), the blood flow did not differ significantly from that on the control side. Biochemical studies in the animals with purulent sinusitis demonstrated that lactate concentration in the mucosa was significantly higher as compared to the control side. The glucose concentration was significantly lower in the mucosa of the infected side, as was the ATP content of the sinus mucosa in purulent sinusitis. These results indicate an increased glycolysis as well as a relative energy depletion in the sinus mucosa in purulent sinusitis, which could result in an impaired epithelial function.