Bitter tastants are recently introduced as potential hunger-suppressive compounds, the so-called "Bitter pill". However, the literature about bitter administration lacks consistency in methods and findings. We want to test whether hunger ratings and hormone plasma levels are affected by: 1) the site of administration: intragastrically (IG) or intraduodenally (ID), 2) the bitter tastant itself, quinine hydrochloride (QHCl) or denatonium benzoate (DB), and 3) the timing of infusion. Therefore, 14 healthy, female volunteers participated in a randomized, placebo-controlled six-visit crossover study. After an overnight fast, DB (1µmol/kg), QHCl (10µmol/kg) or placebo were given IG or ID via a nasogastric feeding tube. Blood samples were taken 10 min prior to administration and every 10 min after administration for a period of 2 hours. Hunger was rated at the same timepoints on a visual analogue scale (VAS). ID bitter administration did not affect hunger sensations, motilin or acyl-ghrelin release compared with its PLC infusion. IG QHCl infusion tended to suppress hunger increase, especially between 50-70 minutes after infusion, simultaneously with reduced motilin values. Here, acyl-ghrelin was not affected. IG DB did not affect hunger or motilin, however acyl-ghrelin levels were reduced 50-70 minutes after infusion. Plasma values of glucagon-like peptide 1 and cholecystokinin were too low to be properly detected or to have any physiological relevance. In conclusion, bitter tastants should be infused into the stomach to reduce hunger sensations and orexigenic gut peptides. QHCl has the best potential to reduce hunger sensations, and it should be infused 60 minutes before food intake.

中文翻译：

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胃肠系统中苦味剂给药的内分泌影响 - 胃内与十二指肠内给药

最近引入了苦味剂作为潜在的抑制饥饿的化合物，即所谓的“苦丸”。然而，关于苦味给药的文献在方法和发现上缺乏一致性。我们想测试饥饿等级和激素血浆水平是否受以下因素影响：1) 给药部位：胃内 (IG) 或十二指肠内 (ID)，2) 苦味剂本身、盐酸奎宁 (QHCl) 或苯甲地那铵 (DB) , 和 3) 输液的时机。因此，14 名健康女性志愿者参与了一项随机、安慰剂对照的六次访问交叉研究。禁食一夜后，通过鼻胃管给予 DB (1μmol/kg)、QHCl (10μmol/kg) 或安慰剂 IG 或 ID。在给药前 10 分钟和给药后每 10 分钟采集血样，持续 2 小时。在视觉模拟量表 (VAS) 的相同时间点对饥饿进行评分。与其 PLC 输注相比，ID 苦味给药不影响饥饿感、胃动素或酰基-生长素释放肽的释放。IG QHCl 输注倾向于抑制饥饿感增加，尤其是在输注后 50-70 分钟之间，同时降低胃动素值。在这里，酰基-生长素释放肽没有受到影响。IG DB 不影响饥饿或胃动素，但在输注 50-70 分钟后酰基-生长素释放肽水平降低。胰高血糖素样肽 1 和胆囊收缩素的血浆值太低而无法正确检测或具有任何生理相关性。总之，应将苦味剂注入胃中以减少饥饿感和促食欲的肠道肽。QHCl 最有可能减少饥饿感，