Effect of propofol on salivary secretion from the submandibular, sublingual, and labial glands during intravenous sedation

BACKGROUND: Recent animal studies have suggested the role of GABA type A (GABA-(A)) receptors in salivation, showing that GABA-(A) receptor agonists inhibit salivary secretion. This study aimed to evaluate the effects of propofol (a GABA-(A) agonist) on salivary secretions from the submandibular, sublingual, and labial glands during intravenous sedation in healthy volunteers. METHODS: Twenty healthy male volunteers participated in the study. They received a loading dose of propofol 6 mg/kg/h for 10 min, followed by 3 mg/kg/h for 15 min. Salivary flow rates in the submandibular, sublingual, and labial glands were measured before, during, and after propofol infusion, and amylase activity was measured in the saliva from the submandibular and sublingual glands. RESULTS: We found that the salivary flow rates in the submandibular, sublingual, and labial glands significantly decreased during intravenous sedation with propofol (P < 0.01). Similarly, amylase activity in the saliva from the submandibular and sublingual glands was significantly decreased (P < 0.01). CONCLUSION: It can be concluded that intravenous sedation with propofol decreases salivary secretion in the submandibular, sublingual, and labial glands via the GABA-(A) receptor. These results may be useful for dental treatment when desalivation is necessary.