Pig bronchial mucous membrane: a model system for assessing respiratory mucus release in vitro.
A convenient organ culture system is described in which fragments of mucous membrane isolated from bronchi of the pig were maintained in either screw-cap tubes or multiwell tissue culture plates. The mucous membrane of the pig bronchus, like that of the human, is rich in mucus-secreting submucosal glands and can respond to cholinergic stimulation in vitro by releasing either L-[3H]fucose- or L-[3H]serine-labeled acid-precipitable macromolecules. Reproducible cholinergic-mediated release of labeled macromolecules was attained by first washing the mucous membrane fragments in serum-free modified Earles medium (Dulbecco's) for 120 min at 4 degrees C. Maximum stimulation was obtained when the incubation medium was supplemented with 0.5-2.0% horse serum. Approximately 50% of L-[3H]fucose-labeled macromolecules were eluted in the void volume from a column of Sepharose CL-6B in 6 M urea. Cochromatography of L-[3H]- and L-[14C]fucose-labeled glycoproteins released by mucous membranes of control and methacholine-treated tissue fragments failed to reveal any significant difference in any specific population of fucose-labeled glycoproteins. It is concluded that, as a whole, many different labeled molecules are released in response to cholinergic stimulation. Taken together, these results suggest that the mucous membrane of the porcine bronchus is a useful in vitro model for studying respiratory mucus secretion.
D000818:Animals; D001790:Blood Physiological Phenomena; D001980:Bronchi / Q000187:drug effects / Q000378:metabolism* / Q000648:ultrastructure; D005260:Female; D006023:Glycoproteins / Q000378:metabolism; D006736:Horses; D008297:Male; D016210:Methacholine Chloride; D008688:Methacholine Compounds / Q000494:pharmacology; D009092:Mucous Membrane / Q000187:drug effects / Q000378:metabolism; D009093:Mucus / Q000378:metabolism*; D009924:Organ Culture Techniques; D013552:Swine
D006023:Glycoproteins; D008688:Methacholine Compounds; D016210:Methacholine Chloride