AMYLASE SECRETION BY CULTURED PORCINE PAROTID CELLS

The similarity of porcine and human physiology and the availability of slaughterhouse tissues suggests the use of porcine parotid cells as a model for amylase secretion. A procedure is described for the isolati on of porcine parotid cells by collagenase-P/dispase digestion of the tissue. The preparation consisted of individual cells and small aggreg ates that were maintained in primary culture, during which the cells f ormed aggregates that firmly attached to the plastic substrate. The am ylase content of the cultured cells remained adequate for assay of sec retory activity during culture for one week after isolation. Depending upon variations in experimental treatments, the cultured cells secret ed approx. 35-65% of cellular amylase in response to a carbachol chall enge. The cells were slightly responsive to long exposures to isoprote renol, and were unresponsive to nicotine, elevated extracellular K+ or substance P. Secretion induced by carbachol required extracellular Ca 2+ was inhibited by atropine and occurred with a nearly linear respons e over a 30-min period. The Ca2+ ionophore A23187 was also a potent se cretagogue for amylase secretion, producing levels of secretion equal to that induced by carbachol. The ease of preparation and the retentio n of amylase during primary culture suggests that the preparation will be useful in studies on muscarinic receptor-mediated control of amyla se secretion.