ラット顎下腺に対する交感神経刺激および味覚刺激によるSIgA分泌量の変化

We studied the influence of sympathetic nerve and taste stimulation on salivary immunoglobulin A secretion in the rat submandibular gland. Although the flow of the saliva evoked by β-adrenoceptor stimulation was very small in volume, secretion evoked by both acidity and bitterness stimulation was greater than from sympathetic stimulation. A marked secretion of peroxidase was found evoked by isoprenaline. Similar levels of SIgA secretion were evoked by each stimulus. Amylase secretion was enhanced by isoprenaline, citric acid and quinine stimulation. In particular, citric acid was significantly different compared with isoprenaline. A similar level of SIgA secretion was evoked by each of the stimuli. SIgA secretion evoked by both isoprenaline and quinine was significantly inhibited by propranolol. Propranolol had only a slight inhibitory effect on citric acid stimulation. The peroxidase level in response to isoprenaline was remarkably reduced by propranolol administration. Although propranolol was less effective on peroxidase secretion evoked by citric acid, quinineinduced peroxidase stimulation was inhibited by propranolol. However, the amylase activity evoked by acidity was weaker than that of sympathetic stimulated saliva. This differencewas attributable to the influence of the nervous system on IgA secretion through input to the submandibular gland via not only the sympathetic nerves, but also the parasympathetic nerves. These results indicate that the salivary secretion of SIgA is regulated by nerve impulses and that acidity imparts a greater effect on SIgA secretion than does solitary sympathetic stimulation alone.大阪歯科大学201