The Coadministration of Paroxetine and Low-Dose Aspirin Synergistically Enhances Gastric Ulcerogenic Risk in Rats

Abstract

Cerebral infarction (CI) is one of the highly mortal diseases. It has been reported that the use of an anti-platelet drug for the treatment of CI significantly decreased the patient's risk of a future stroke by 23%.1) Low-dose aspirin, the most frequently used anti-platelet drug in Japan, could reduce the risk of future strokes with dose range in the 50 to 200 mg per day range. 2,3) On the other hand, depression is the major co-morbid disorders in CI sequelae. Selective serotonin reuptake inhibitors (SSRI) are the major antidepressants used to treat depression. Therefore, it is likely to coadminister low-dose aspirin and SSRIs in order to prevent future strokes and to treat depression. Only a few clinical studies have examined the risk associated with the coadministration of low-dose aspirin and SSRIs, 4,5) even though both drugs have similar adverse effects on gastric mucosa. [6][7][8] Former 2 studies indicated that the coadministration of lowdose aspirin and SSRIs increased the risk of abnormal bleeding in stomach, which is closely related to gastric ulcers. In the present study, we investigated the ulcerogenic effect induced by the coadministration of low-dose aspirin and paroxetine, major one of the SSRIs in rats. MATERIALS AND METHODS AnimalsMale Wistar rats (200-250 g) were used. Animals were fed on diet with free access to water under standard humidity and temperature. Animals were fasted for 24 h before ulcerogenic experiments.Drugs Paroxetine hydrochroride (GlaxoSmithKline), low-dose aspirin (Merck), indomethacin (Sigma Chemicals, St. Louis, MO, U.S.A.) and serotonin (Nacalai, Japan) were used. We used Paxil ® tablets as paroxetine hydrochroride. Paxil ® tablets contain calcium hydrogen phosphate, sodium carboxymethylstarch, magnesium stearate, hydroxypropyl methylcellulose 2910, macrogol 400, iron and sesquioxide, polysorbate 80, titanium dioxide. However, these ingredients were not enough to express their actions. A dose of 50 mg/kg of aspirin was selected as low-dose aspirin.9) Low-dose aspirin was suspended and paroxetine and indomethacin were dissolved in the distillated water, and we administrated them (2 ml/kg) orally, and serotonin was subcutaneously administered at 1, 5 or 10 ml/kg. Distillated water (2 ml/kg) or saline (5 ml/kg) were orally or subcutaneously administered to the control animals.Determination of Gastric Acid Secretion In order to measure the gastric acid secretion, a pylorus-ligation method was used. A pylorus ligature was performed 30 min after orally or subcutaneously administration of the drugs. Paroxetine (1, 3 or 10 mg/kg) or serotonin (1, 5 or 10 mg/kg) was selected as proper doses from many published papers. Animals were sacrificed 2 h after pylorus ligature by cervical dislocation, the abdomen was opened and oesophagus was held by clamp. The stomach was removed, and was inspected external apparence. Its content was drained into a centrifuge tube and centrifuged at 3000 rpm for 5 min. The supernatant volume was measured with micropipette and pH was recorded with a digita...

Meta-analysis of the Risk of Upper Gastrointestinal Hemorrhage with Combination Therapy of Selective Serotonin Reuptake Inhibitors and Non-steroidal Anti-inflammatory Drugs

“…In addition, NSAIDs inhibit production of prostaglandin I2 (PGI2), which inhibits platelet aggregation, 19) but whether SSRIs affect this process is unclear. Hence, results of these studies suggest that the increase in risk with combination use of SSRIs and NSAIDs, which affect the three greatest risk factors for gastric injury, is additive.…”

Protective and Therapeutic Effects of Argyreia speciosa against Ethanol-Induced Gastric Ulcer in Rats

“…The samples were centrifuged at 3000 x g for 15 min, and the supernatants were used for the determination of PGE 2 using an enzyme immunoassay kit (Cayman Chemical Co., Ann Arbor, MI, USA). PGE 2 was expressed as ng/mg protein (Yamaguchi et al, 2008).…”

Risk of Bleeding Related to Selective and Non-selective Serotonergic Antidepressants: A Case/Non-case Approach Using Data from Two Pharmacovigilance Databases

“…The most important mechanisms appear to be SSRI-induced inhibition of serotonin uptake in platelets resulting in decreased serotonin release from platelets in case of vascular injury with the consequence of diminished serotonin-triggered platelet aggregation and vasoconstriction (prolongation of bleeding time and reduced platelet aggregability and activity) [19,32,33]. However, other mechanisms such as SSRI-induced increase in gastric acid secretion that may exhibit ulcerogenic effects (as shown already in rodent models [34,35] and suggested by increased rates of first prescriptions of peptic ulcer drugs in patients receiving NSAID/SSRI compared to NSAID/non-selective antidepressant [36]) [19], SSRI-related pharmacokinetic interactions with the cytochrome P450 (CYP) enzymes (particularly regarding paroxetine, fluvoxamine, and fluoxetine) inhibiting the metabolisation of NSAIDs and antiplatelet drugs [19,37] as well as a possible influence of SSRI on other metabolic pathways involved in haemostasis [38] are discussed as well.…”