Hyperosmolar Solutions Stimulate Mucus Secretion in the Ferret Trachea: Hyperosmolar Solution
The amount of lysozyme secreted was expressed as lysozyme per trachea tissue weight (micrograms per gram).
Mucin Secretion With Only the Tracheal Lumen Exposed to Hyperosmolar Solution
To evaluate whether hyperosmolar solution stimulates tracheal secretion via the luminal side in this model, whole trachea were used. Saline solution, 1.69 g/dL, or KHS was added into the inside of the trachea, and both ends of the trachea were tied. These tied tracheae (n = 2 each) were incubated for 20 min at 38°C with 1.69 g/dL (597 mOsm) of saline solution or KHS (288 mOsm/L) as follows: (1) inside saline solution-outside KHS, (2) outside saline solution-inside KHS, or (3) control inside and outside KHS. The inside solutions were collected and diluted with 10 mL of KHS for mucin analysis. my canadian pharmacy
Evaluation of Secretory Pathways Using Inhibitors of Mucin Secretion
We also evaluated the secretory response to hyperosmolar solution along with inhibitors. After 2 h of resting in KHS, ferret tracheal segments were incubated for 20 min with each inhibitor in KHS or only in KHS as a control (period 1), and then incubated for another 20 min in hyperosmolar solution with each inhibitor in KHS, or with only KHS (negative control) or with hyperosmolar solution only (period 2). Atropine, 104 mol/L, was used as a muscarinic antagonist at a concentration shown to inhibit methacholine-induced tracheal secretion (104 mol/L of atropine against 105 mol/L of methacholine). We used nordi-hydroguaiaretic acid (NDGA), 105 mol/L, as an inhibitor of the cyclooxygenase and lipoxygenase pathways of arachidonic acid metabolism. NDGA is also a free-radical scavenger. We also used protease inhibitors containing phenylmethylsulfonyl fluoride as an inhibitor of serine protease, leupeptin as a nonspecific protease inhibitor, and pepstatin A as an acid protease inhibitor. All agents were purchased from Sigma Chemical (St. Louis, MO).