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Kratom is an herbal substance that produces opioid-like and stimulant-like effects. Kratom contains bioactive alkaloids that include mitragynine and 7-OH mitragynine. Both substances activate mu-opioid receptors as well as bind to adrenergic, dopaminergic, and serotonergic receptors, which may be responsible for the stimulant effects. There is no current approved use of kratom or kratom products by the USFDA, but it is currently being used by individuals for management of drug withdrawal, pain, fatigue, and mental health problems. Multiple serious but rare side-effects have been reported, including gastrointestinal, respiratory, psychiatric, cardiovascular issues. Thus, the USDEA considers it to be a Drug and Chemical of Concern and has warned the public against risks of Kratom use. As such, research on Kratom products is necessary to better understand risks and inform policy regarding regulation. Here, we sought to develop a method by which the pharmacologically active mitragynine and its active metabolite 7-OH mitragynine could be measured in various kratom products. The quantification of each utilized high pressure liquid chromatography with ultra-violet detection (HPLC-UV). An XBridge C18 column with 3.5 um particle size, 4.6 x 150 mm was used, and separation was achieved using a gradient elution with acetonitrile and 0.1% formic acid. The flow rate was 1 mL/min, and the oven temperature was set at 40oC. UV detection was at 254 nm. The 7-OH mitragynine peak was visible at 2.5 minutes and the mitragynine at 3.55 minutes. In conclusion, this method has potential to provide utility for detection and quantification of pharmacologically active compounds in kratom products.

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Anxiety is marked by impaired inhibition of distraction (Eysenck et al., 2007). It is unclear whether these impairments are reduced or exacerbated when loading working memory (WM) with non-affective information. Cardiac vagal control has been related to emotion regulation and may serve as a proxy for load-related inhibition under anxiety (Thayer and Lane, 2009). The present study examined whether: (1) the enhancing and impairing effects of load on inhibition exist together in a nonlinear function, (2) there is a similar association between inhibition and concurrent vagal control, (3) nonlinear relations depend on trait anxiety. During anxiogenic threat-of-noise, 116 subjects maintained a digit series of varying lengths (0, 2, 4, 6 digits) while completing a visual flanker task. The task was broken into four blocks, with a baseline period preceding each. ECG was acquired throughout to quantify vagal control as high-frequency heart rate variability (HRV). There were significant quadratic relations of WM load to flanker performance and to HRV, but no associations between HRV and performance. Trait anxiety did not moderate any relations among HRV, load, and inhibition. Results indicate that low load was associated with relatively better inhibition and increased HRV. Findings suggest that attentional performance under anxiety depends on the availability of WM resources, which might be reflected by vagal control. These results have implications for treating anxiety disorders, in which emotion regulation can be optimized for attentional focus. / Ph. D.

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Thesis (Ph.D.)--University of Alberta, 2010. / A thesis submitted to the Faculty of Graduate Studies and Research in partial fulfillment of the requirements for the degree of Doctor of Philosophy, Centre of Neuroscience. Title from pdf file main screen (viewed on April 18, 2010). Includes bibliographical references.

Thesis (Ph.D.)--Flinders University, Dept. of Human Physiology, Centre for Neuroscience. / Typescript bound. Includes bibliographical references: (leaves 187-191) Also available electronically via the World Wide Web.

Made available in DSpace on 2014-06-11T19:22:49Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-08-14Bitstream added on 2014-06-13T19:08:19Z : No. of bitstreams: 1 hoshi_ra_me_prud.pdf: 470187 bytes, checksum: 5cba677581b43beb6b7309e781ff9714 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O sistema nervoso autônomo (SNA) desempenha um papel importante na regulação dos processos fisiológicos do organismo humano tanto em condições normais quanto patológicas. Dentre as técnicas utilizadas para sua avaliação, a variabilidade da frequência cardíaca (VFC) tem emergido como uma medida simples e não-invasiva dos impulsos autonômicos, representando um dos mais promissores marcadores quantitativos do balanço autonômico. A VFC descreve as oscilações no intervalo entre batimentos cardíacos consecutivos (intervalos R-R), assim como oscilações entre frequências cardíacas instantâneas consecutivas. Trata-se de uma medida que pode ser utilizada para avaliar a modulação do SNA sob condições fisiológicas, tais como em situações de vigília e sono, diferentes posições do corpo, treinamento físico, e também em condições patológicas. Mudanças nos padrões da VFC fornecem um indicador sensível e antecipado de comprometimentos na saúde. Uma alta variabilidade na frequência cardíaca é sinal de boa adaptação, caracterizando um indivíduo saudável, com mecanismos autonômicos eficientes, enquanto que, baixa variabilidade é frequentemente um indicador de adaptação anormal e insuficiente do SNA, implicando a presença de mau funcionamento fisiológico no indivíduo. Diante da sua importância como um marcador que reflete a atividade do SNA sobre o nódulo sinusal e como uma ferramenta clínica para avaliar e identificar comprometimentos na saúde, este artigo revisa aspectos conceituais da VFC, dispositivos de mensuração, métodos de filtragem, índices utilizados para análise da VFC, limitações de utilização e aplicações clínicas da VFC. / Autonomic nervous system (ANS) plays an important role in the regulation of the physiological processes of the human organism during normal and pathological conditions. Among the techniques used in its evaluation, the heart rate variability (HRV) has arising as a simple and non-invasive measure of the autonomic impulses, representing one of the most promising quantitative markers of the autonomic balance. The HRV describes the oscillations in the interval between consecutive heart beats (RR interval), as well as the oscillations between consecutive instantaneous heart rates. It is a measure that can be used to assess the ANS modulation under physiological conditions, such as wakefulness and sleep conditions, different body positions, physical training and also pathological conditions. Changes in the HRV patterns provide a sensible and advanced indicator of health involvements. Higher HRV is a signal of good adaptation and characterizes a health person with efficient autonomic mechanisms, while lower HRV is frequently an indicator of abnormal and insufficient adaptation of the autonomic nervous system, provoking poor patient's physiological function. Because of its importance as a marker that reflects the ANS activity on the sinus node and as a clinical instrument to assess and identify health involvements, this study reviews conceptual aspects of the HRV, measurement devices, filtering methods, indexes used in the HRV analyses, limitations in the use and clinical applications of the HRV.