The effects of indomethacin and thiorphan on bradykinin-induced albumin output and submucosal gland secretion in the ferret trachea in vivo.

In the ferret liquid-filled trachea in vivo, intraluminal bradykinin (BK, 3-300 microM) produced concentration-dependent increases in the output of lysozyme from submucosal gland serous cells and albumin movement into the lumen. Baseline outputs of albumin and lysozyme were not altered significantly by intraluminal indomethacin (10 microM) or thiorphan (10 microM). However, intraluminal indomethacin completely blocked the BK-induced increase in albumin output. Intraluminal thiorphan (10 microM) did not significantly potentiate BK-induced albumin output, although mean output was higher. Neither indomethacin nor thiorphan significantly altered BK-induced lysozyme output, although mean output was reduced in the presence of indomethacin. Thus BK increases albumin output and may increase lysozyme output via the action of cyclooxygenase products. Inhibition of neutral endopeptidase activity may enhance the action of BK on albumin output.