흰쥐 턱밑샘에서 fluoxetine 투여에 의한 침분비 및 muscarinic acetylcholine receptor M3 발현 감소

Abnormal salivation including hyposalivation, xerostomia, and changes in saliva composition is important side effect related to taking antidepressants. Selective serotonin re-uptake inhibitor (SSRI) antidepressants have also these side effects. However, hyposalivation mechanism and anticholinergic action by SSRIs is not fully understood. In this study, we have examined changes in salivation and cholinergic signal proteins levels in the salivary gland of the rat after chronic fluoxetine administration. Animals were divided in to 5 groups with the control, lowdose p.o. (20 mg/kg p.o.), highdose p.o. (40 mg/kg p.o.), lowdose i.p. (20 mg/kg i.p.) and highdose i.p. (40 mg/kg i.p.) groups. After fluoxetine administration for 4 weeks, saliva collection began to determine the salivary flow rate. Next, salivary glands were removed, the salivary tissues processes for Western blot analysis (for muscrinci acetylcholine receptor M3 (mAchR M3) and aquaporin5 (AQP5)). The salivary flow rate was decreased with fluoxetine dose in the i.p. groups, but not in the p.o. groups. This decreasing pattern was similar to mAchR M3 and AQP5 protein level. These finding suggest that the hyposalivation by fluoxetine may related anticholinergic action.