Effect of fenoterol on secretions of an isolated single submucosal gland from the trachea.
The mechanism of secretion of airway submucosal glands is not known. Although the existence of cyclic AMP in the submucosal gland has been reported, the effect of stimulation of the gland by exogenous cyclic AMP has been denied. We hypothesize that the negative effect of exogenous cyclic AMP is due to the modified influence of ciliated epithelium on the submucosal gland, because epithelium releases chemical mediators. We isolated a single submucosal gland from a cat trachea. We measured mucous glycoprotein labeled with [3H]-glucosamine from the isolated submucosal glands. With stimulation of dibutyryl cyclic AMP, a percent increase of the secretion above control was about 3 times in isolated glands. Methacholine and fenoterol secreted mucus largely in isolated glands. We suggest that cyclic AMP increased the secretion in the glands. The difference of quantity of secretions between methacholine and fenoterol has been investigated further.
D000818:Animals; D003994:Bucladesine / Q000494:pharmacology; D002415:Cats; D005280:Fenoterol / Q000494:pharmacology*; D066298:In Vitro Techniques; D016210:Methacholine Chloride; D008688:Methacholine Compounds / Q000494:pharmacology; D010827:Physiology / Q000295:instrumentation; D014132:Trachea / Q000378:metabolism*
D008688:Methacholine Compounds; D016210:Methacholine Chloride; D005280:Fenoterol; D003994:Bucladesine