Martinez José Antônio Baddini, Rocha Fábio Senra, Sobrani Elizabet, Galhardo Fabíola Paula Lovreto, Terra Filho João
Departamento de Medicina Interna, Faculdade de Medicina de Ribeirão Preto, São Paulo, Brazil.
Sao Paulo Med J. 2002 Sep 2;120(5):141-5. doi: 10.1590/s1516-31802002000500004.
Dyspnea remains a therapeutic challenge, especially in chronic respiratory conditions. Recent studies have shown that the induction of unpleasant dyspnea sensations activates areas in the insular cortex.
This study was designed to investigate the potential effects of ondansetron, a potent anti-serotonin agent, on induced dyspnea sensation.
A randomized double blind study.
Pulmonary Function Laboratory of Hospital das Clínicas de Ribeirão Preto.
Ten healthy male volunteers (mean age +/- standard error = 23.1 +/- 0.41 years) without respiratory diseases and showing normal spirometric tests.
Uncomfortable breathing was induced in the volunteers on two different days, via the use of inspiratory resistors (loads of 0, 7, 14 and 21 cm H2O/l/sec) and breathholding, two hours after taking 8 mg of ondansetron (Ond) or placebo (Plac).
Respiratory discomfort during breathing under loading was evaluated on a 100-mm visual analog scale. The maximum length of time of voluntary apnea was measured in seconds.
The mean maximum voluntary apnea time did not differ between the ondansetron and placebo days (Plac = 96 +/- 6.6 sec vs. Ond = 100 +/- 7.9 sec). Ondansetron did not influence the dyspnea sensation induced by different inspiratory loads (0 cm H2O/l/sec: Ond = 1.4 mm +/- 0.44 vs. Plac = 2.1 +/- 0.85 mm; 7 cm H2O/l/sec: Ond = 16.6 +/- 2.74 mm vs. Plac = 13.7 +/- 2.06 mm; 14 cm H2O/l/sec; Ond = 30.5 +/- 4.50 mm vs. Plac = 27.1 +/- 3.44 mm; 21 cm H2O/l/sec: Ond = 50.3 +/- 6.72 mm vs. Plac = 49.4 +/- 6.72 mm). Ondansetron led to significant decreases in tidal volume under basal conditions and when breathing under the highest inspiratory loading (0 cm H2O/l/sec: Ond = 0.83 +/- 0.26 l vs. Plac = 1.0 +/- 0.28 l; 21 cm H2O/l/sec: Ond = 0.86 +/- 0.23 l vs. Plac = 1.1 +/- 0.22 l)
The present results suggest that 5-HT3 receptors do not play an important role in the mediation of dyspnea sensations.
呼吸困难仍然是一个治疗难题，尤其是在慢性呼吸道疾病中。最近的研究表明，诱发不愉快的呼吸困难感觉会激活脑岛皮质区域。
本研究旨在调查强效抗血清素药物昂丹司琼对诱发的呼吸困难感觉的潜在影响。
随机双盲研究。
里贝朗普雷图临床医院肺功能实验室。
10名无呼吸系统疾病且肺量计测试正常的健康男性志愿者（平均年龄±标准误差=23.1±0.41岁）。
在服用8毫克昂丹司琼（Ond）或安慰剂（Plac）两小时后，通过使用吸气电阻器（负荷为0、7、14和21厘米水柱/升/秒）和屏气，在两个不同的日子里诱发志愿者呼吸不适。
在100毫米视觉模拟量表上评估负荷呼吸时的呼吸不适。以秒为单位测量自主呼吸暂停的最长时间。
昂丹司琼组和安慰剂组的平均最大自主呼吸暂停时间无差异（Plac = 96±6.6秒 vs. Ond = 100±7.9秒）。昂丹司琼不影响不同吸气负荷诱发的呼吸困难感觉（0厘米水柱/升/秒：Ond = 1.4毫米±0.44 vs. Plac = 2.1±0.85毫米；7厘米水柱/升/秒：Ond = 16.6±2.74毫米 vs. Plac = 13.7±2.06毫米；14厘米水柱/升/秒：Ond = 30.5±4.50毫米 vs. Plac = 27.1±3.44毫米；21厘米水柱/升/秒：Ond = 50.3±6.72毫米 vs. Plac = 49.4±6.72毫米）。昂丹司琼导致基础状态下和最高吸气负荷呼吸时潮气量显著降低（0厘米水柱/升/秒：Ond = 0.83±0.26升 vs. Plac = 1.0±0.28升；21厘米水柱/升/秒：Ond = 0.86±0.23升 vs. Plac = 1.1±0.22升）
目前的结果表明，5-HT3受体在呼吸困难感觉的介导中不发挥重要作用。
