Regional differences in vascular responsiveness of nasal mucosae isolated from naive guinea pigs

Objective In the present study, the contractile response to norepinephrine (NE) and relaxing response to histamine and leukotriene D4 (LTD4) were compared among the nasal mucosae of septa (S) and lateral (L) and medial turbinates (M) isolated from naive male Hartley guinea pigs. Methods The isometrical tension of the isolated nasal mucosae of the above regions was measured at a resting tension of 0.5 g by using a standard organ-bath technique. Results In each mucosal strip, NE induced a contraction in a concentration-dependent manner. A significant difference in efficacy (maximal response) of NE was found (L > M > S). In mucosal strips precontracted with NE (3 × 10−5 M), both histamine and LTD4 induced relaxing responses. The efficacy of histamine in S was significantly greater than those in L and M. The potency order of LTD4 was L > M > S; a significant difference was observed between L and S. Conclusion In conclusion, the present study demonstrated a distinct regional difference in the response to contractile and relaxant agonists of isolated nasal mucosae of guinea pigs.