Secretogogue responses of leukotriene C4, D4: comparison of potency in canine trachea in vivo.

By the use of close arterial injection of leukotrienes into the circulation supplying the upper cervical canine trachea, it has been possible to assess the secretogogue effects of leukotriene C4, and D4 on mucus secretion. Both LTC4 and LTD4 increased mucus secretion over baseline levels by a statistically significant level (p = less than 0.05). LTD4 was more potent than C4 with relative potencies of 2500, 320, 630, and 500 based on hillock formation (a measure of secretion) at 1, 2, 3, and 4 minutes after injection. The overall difference in potency in this animal model of mucus production was LTD4 greater than C4 by 1000-fold.