The effect of doxapram on brain imaging in patients with panic disorder

Laboratory of Clinical Psychobiology, Department of Psychiatry, Mount Sinai School of Medicine, One Gustave L. Levy Place, New York, NY 10029, USA.
European Neuropsychopharmacology (Impact Factor: 4.37). 11/2007; 17(10):672-86. DOI: 10.1016/j.euroneuro.2007.04.002
Source: PubMed


Administration of doxapram hydrochloride, a respiratory stimulant, is experienced by panic disorder patients to be similar to panic attacks but has reduced emotional effect in normal volunteers, thus providing a laboratory model of panic for functional imaging. Six panic patients and seven normal control subjects underwent positron emission tomography with (18)F-deoxyglucose imaging after a single-blinded administration of either doxapram or a placebo saline solution. Saline and doxapram were administered on separate days in counterbalanced order. Patients showed a greater heart rate increase on doxapram relative to saline than controls, indicating differential response. On the saline placebo day, patients had greater prefrontal relative activity than controls. In response to doxapram, patients tended to decrease prefrontal activity more than controls, and increased cingulate gyrus and amygdala activity more than controls. This suggests that panic disorder patients activate frontal inhibitory centers less than controls, a tendency that may lower the threshold for panic.

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Available from: Amir Garakani
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    • "In contrast, pharmacological provocation studies often fail in detecting panic-associated amygdala activation in patients (e.g., Boshuisen et al. 2002; Kent et al. 2005; Reiman et al. 1989) as well as in controls (e.g., Javanmard et al. 1999; Schunck et al. 2006, 2011). Some studies find amygdala involvement, but often less pronounced as expected (Eser et al. 2009; Garakani et al. 2007). This further indicates differences between provoked and spontaneous panic attacks. "
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