Interaction of carbachol and isoproterenol on O2 consumption and morphology of isolated acini from rat parotid gland.

Acini from rat parotid gland were isolated by digestion with collagenase. Oxygen consumption rates were measured after stimulation with carbachol and isoproterenol applied either simultaneously or subsequently to each other. The corresponding morphological effects were examined by electron microscopy. The results demonstrate that a) carbachol always induces increased O2 consumption rates with concomitant formation of vacuoles, b) isoproterenol stimulates exocytosis and higher O2 consumption rates only when added before carbachol and c) isoproterenol has no effect when given simultaneously with or subsequently to carbachol.