Argiolas A, Melis M R, Stancampiano R, Gessa G L
Department of Neurosciences, University of Cagliari, Italy.
Pharmacol Biochem Behav. 1990 Mar;35(3):601-5. doi: 10.1016/0091-3057(90)90297-u.
The effect of verapamil, flunarizine, nimodipine, nicardipine, and nifedipine, calcium channel inhibitors, and of indomethacin and aspirin, inhibitors of prostaglandin synthesis, on penile erection and yawning induced by oxytocin was studied in male rats. All calcium channel inhibitors given intraperitoneally (IP) 60 min before the intracerebroventricular (ICV) injection of oxytocin (30 ng) prevented in a dose-dependent manner oxytocin effect. Nimodipine and nicardipine were the most effective being active at doses between 5 and 20 mg/kg, while the others were active at doses higher than 15 mg/kg. Prevention of oxytocin effect was also seen after ICV injection of the above compounds. Unlike calcium channel inhibitors, indomethacin given either IP (10 and 50 mg/kg) or ICV (50 micrograms), or aspirin (100 mg/kg IP) were ineffective. Microinjection of calcium, but not of prostaglandin E2 and prostaglandin F2 alpha in the paraventricular nucleus of the hypothalamus, the brain area most sensitive for the induction of the above behavioral responses by oxytocin, induced a symptomatology similar to that induced by oxytocin. The present results suggest that calcium might be the second messenger which mediates the expression of penile erection and yawning induced by oxytocin.
在雄性大鼠中，研究了维拉帕米、氟桂利嗪、尼莫地平、尼卡地平、硝苯地平等钙通道抑制剂以及吲哚美辛和阿司匹林等前列腺素合成抑制剂对催产素诱导的阴茎勃起和打哈欠的影响。在脑室内（ICV）注射催产素（30 ng）前60分钟腹腔内（IP）给予所有钙通道抑制剂，均以剂量依赖性方式阻止了催产素的作用。尼莫地平和尼卡地平最有效，在5至20 mg/kg的剂量下有活性，而其他药物在高于15 mg/kg的剂量下有活性。脑室内注射上述化合物后也观察到对催产素作用的阻止。与钙通道抑制剂不同，腹腔内给予吲哚美辛（10和50 mg/kg）或脑室内给予（50微克），或腹腔内给予阿司匹林（100 mg/kg）均无效。在下丘脑室旁核微量注射钙，但不注射前列腺素E2和前列腺素F2α，该脑区对催产素诱导上述行为反应最为敏感，可诱发类似于催产素诱发的症状。目前的结果表明，钙可能是介导催产素诱导的阴茎勃起和打哈欠表达的第二信使。
