Estudo químico e da atividade biológica cardiovascular do óleo essencial de folhas de Alpinia zerumbet (Pers.) B.L.Burtt & R.M.Sm. em ratos / Phytochemistry and cardiovascular biological activity of the essential oil from leaves of Alpinia zerumbet (Pers.) B.L. Burtt & R.M.Sm. in rats

A espécie vegetal Alpinia zerumbet (Pers.) B.L.Burtt & R.M. Sm. é popularmente empregada para o tratamento de diversas enfermidades, entre elas a hipertensão. Avaliar a composição química, a atividade antihipertensiva e ação na hipertrofia cardíaca do óleo essencial das folhas de Alpinia zerumbet (OEAZ) em ratos foram os objetivos deste estudo. O OEAZ, obtido por hidrodestilação em aparelho Clevenger, teve sua composição química analisada em cromatografia gasosa acoplada à espectrometria de massas (CG-EM). Foram identificados 14 constituintes, sendo terpinen-4-ol (37,45 por cento) o majoritário, seguido pelos óxido de cariofileno (7,56 por cento), trans-hidrato de sabineno (6,61 por cento) e 1,8-cineol (4,02 por cento). A avaliação cardiovascular foi feita após o tratamento crônico de ratos espontaneamente hipertensos (SHR) e seus respectivos controles, ratos Wistar-Kyoto (WKY). Os dados hemodinâmicos revelaram redução da pressão arterial média (PAM) no grupo tratado (SHRP: 160 ± 7 mm Hg; p<0,01) em relação ao não tratado (SHR: 180 ± 5 mm Hg). A relação entre peso do ventrículo esquerdo e peso corporal (VE/PC) do SHRP (2,50 ± 0,03 mg g-1; p<0,01) mostrou-se inferior ao SHR (2,61 ± 0,01 mg g-1), confirmando a redução da hipertrofia cardíaca (HC). Os dados de PAM e VE/PC dos animais SHRP foram estatisticamente diferentes quando comparados com os ratos controle (WKY: 116 ± 2 mm Hg e WKYP: 119 ± 4 mm Hg; p<0,05; WKY: 2,15 ± 0,04 mg g-1 e WKYP: 2,17 ± 0,04 mg g-1 ; p<0,01), indicando não ter havido normalização dos mesmos. Conclui-se que o tratamento crônico com OEAZ foi capaz de determinar redução, mas não a normalização, da PAM e da HC de ratos SHR, provavelmente pela presença dos componentes terpinen-4-ol e 1,8-cineol. Estudos com doses maiores ou período de tratamento superior são necessários para avaliar a possibilidade de o OEAZ normalizar os parâmetros analisados (PAM e HC).

Alpinia zerumbet (Pers.) B.L. Burtt & R.M.Sm. is traditionally employed to treat several diseases such as hypertension. The aim of this study was to evaluate the chemical composition, the anti-hypertensive activity and the capacity to reduce cardiac hypertrophy of the essential oil of A. zerumbet leaves (EOAZ) in rats. EOAZ was obtained through hydrodistillation in Clevenger apparatus and its chemical composition was analyzed by gas chromatography-mass spectrometry (GC-MS). Several constituents (14) were identified, terpen-4-ol (37.45 percent) being the major component, followed by caryophyllene oxide (7.56 percent), trans-sabinene hydrate (6.61 percent) and 1,8-cineol (4.02 percent). The cardiovascular effect was investigated after chronic treatment with spontaneously hypertensive rats (SHR) and their respective controls, Wistar-Kyoto rats (WKY). The treated group showed a lower mean arterial pressure (MAP) (SHRP: 160 ± 7 mm Hg; p<0.01) than the untreated group (SHR: 180 ± 5 mm Hg). The ratio of left ventricle-to-body weight (LV/BW) for SHRP was lower (2.504 ± 0.03 mg g-1; p<0.01) than that for SHR (2.162 ± 0.01 mg g-1), confirming the cardiac hypertrophy (CH) reduction. There were significant differences in MAP and CH between SHRP animals and control rats (WKY: 116 ± 2 mm Hg and WKYP: 119 ± 4 mm Hg; p<0.05. WKY: 2.152 ± 0.04 mg g-1 and WKYP: 2.168 ± 0.04 mg g-1; p<0.01), indicating that these values were not normalized. Those data showed that the chronic treatment with EOAZ reduces MAP and CH in SHR probably due to the presence of the compounds terpinen-4-ol and 1,8-cineol. Studies with higher doses or longer treatment periods are necessary to evaluate whether EOAZ can reduce the analyzed parameters (MAP and CH) to normal values.

The effect of an anticipated reverse smoking rule on the perceived distraction of persons attending organizational meetings.

Smokers (n = 41) and nonsmokers (n = 54) were asked to complete parallel questionnaires. Each questionnaire contained 27 questions which described a task-oriented meeting varying in duration and importance or interest value. Three durations (15, 30, and 60 minutes) were crossed with three levels of interest value to produce nine item types. The questionnaires for smokers indicated that for all the meetings smoking was strictly prohibited, while those for the nonsmoker indicated that smoking was allowed and was going on. For each question, subjects were asked to rate the degree of distraction they perceived themselves as experiencing. Nonsmokers perceived themselves as being more distracted by an anticipated reverse smoking rule than did smokers; as length of meeting increased, perceived distraction increased, and as importance of the meeting increased, perceived distraction decreased.