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Background & aimsAlterations in central corticotropin-releasing factor signaling pathways have been implicated in the pathophysiology of anxiety disorders and irritable bowel syndrome (IBS). We aimed to characterize the effects of the corticotropin-releasing factor receptor 1 (CRF-R1) antagonist, GW876008, on brain and skin conductance responses during acquisition and extinction of conditioned fear to the threat of abdominal pain in subjects with IBS and healthy individuals (controls).MethodsWe performed a single-center, randomized, double-blind, 3-period crossover study of 11 women with IBS (35.50 ± 12.48 years old) and 15 healthy women (controls) given a single oral dose (20 mg or 200 mg) of the CRF-R1 antagonist or placebo. Blood-oxygen level-dependent responses were analyzed using functional magnetic resonance imaging in a tertiary care setting.ResultsControls had greater skin conductance responses during acquisition than extinction, validating the fear-conditioning paradigm. In contrast, during extinction, women with IBS had greater skin conductance responses than controls-an effect normalized by administration of a CRF-R1 antagonist. Although the antagonist significantly reduced activity in the thalamus in patients with IBS and controls during acquisition, the drug produced greater suppression of blood-oxygen level-dependent activity in a wide range of brain regions in IBS patients during extinction, including the medial prefrontal cortex, pons, hippocampus, and anterior insula.ConclusionsAlthough CRF signaling via CRF-R1 is involved in fear acquisition and extinction learning related to expected abdominal pain in patients with IBS and controls, this system appears to be up-regulated in patients with IBS. This up-regulation might contribute to the previously reported abnormal brain responses to expected abdominal pain.

Chanting and praying are among the most popular religious activities, which are said to be able to alleviate people's negative emotions. However, the neural mechanisms underlying this mental exercise and its temporal course have hardly been investigated. Here, we used event-related potentials (ERPs) to explore the effects of chanting the name of a Buddha (Amitā bha) on the brain's response to viewing negative pictures that were fear- and stress-provoking. We recorded and analyzed electroencephalography (EEG) data from 21 Buddhists with chanting experience as they viewed negative and neutral pictures. Participants were instructed to chant the names of Amitā bha or Santa Claus silently to themselves or simply remain silent (no-chanting condition) during picture viewing. To measure the physiological changes corresponding to negative emotions, electrocardiogram and galvanic skin response data were also collected. Results showed that viewing negative pictures (vs. neutral pictures) increased the amplitude of the N1 component in all the chanting conditions. The amplitude of late positive potential (LPP) also increased when the negative pictures were viewed under the no-chanting and the Santa Claus condition. However, increased LPP was not observed when chanting Amitā bha. The ERP source analysis confirmed this finding and showed that increased LPP mainly originated from the central-parietal regions of the brain. In addition, the participants' heart rates decreased significantly when viewing negative pictures in the Santa Claus condition. The no-chanting condition had a similar decreasing trend although not significant. However, while chanting Amitā bha and viewing negative pictures participants' heart rate did not differ significantly from that observed during neutral picture viewing. It is possible that the chanting of Amitā bha might have helped the participants to develop a religious schema and neutralized the effect of the negative stimuli. These findings echo similar research findings on Christian religious practices and brain responses to negative stimuli. Hence, prayer/religious practices may have cross-cultural universality in emotion regulation. This study shows for the first time that Buddhist chanting, or in a broader sense, repetition of religious prayers will not modulate brain responses to negative stimuli during the early perceptual stage, but only during the late-stage emotional/cognitive processing. [ABSTRACT FROM AUTHOR]

The article discuses the network based dynamic analysis technique for detecting brain states during both resting and dynamic state. It is reported that the Individualized Network-based Single frame Coactivation Pattern Estimation (INSCAPE) approach has been used to explore the spatiotemporal characteristics of dynamic brain state network configurations at the individual level. It is further reported that the reproducibility of the INSCAPE approach was evaluated by using Pearson correlations.

The article focuses on a study related to the impact of corticotropin-releasing factor (CRF) receptor one antagonist on regional activation and effective connectivity of a stress-sensitive emotional–arousal circuit during abdominal pain. It informs that central effects in the brain region associated with stress response were found during the study. The study was performed with the help of magnetic resonance imaging in human subjects with a diagnosis of irritable bowel syndrome (IBS).

Objective: The aim of this study was to investigate the association between anti-hypertensive drugs, the risk of developing an abdominal aortic aneurysm (AAA), aortic wall stiffness, collagen turnover, and change in aortic diameter. STUDY DESIGN, SETTINGS AND METHODS: Data on present medication, smoking status, and medical history of participants in two population-based aneurysm screening programs in the United Kingdom were collected by use of questionnaire. Aortic elasticity was measured by M-mode ultrasound scanning. A serum radioimmunoassay of the amino-terminal propeptide of type III procollagen was used to assess collagen turnover in one of the patient series., Results: Data from 438 cases with an AAA >29 mm and 5373 controls were analyzed. Calcium-channel blockers were independently associated with AAA. The odds ratio of having an AAA was 2.6 (95% confidence interval [CI], 1.5-4.2) after adjusting for all relevant confounders. Other antihypertensive drugs showed no increased risk. No significant differences in growth rates were found in cases exposed to any of the main antihypertensive drugs. An increased collagen turnover was found in subjects receiving angiotensin-converting enzyme (ACE) inhibitors: 4.26 mg/L (95% CI, 3.73-4.79) compared with 3.62 mg/L (95% CI, 3.49-3.76) for subjects not receiving ACE inhibitors. No differences in type III collagen turnover was found with use of any other antihypertensive drug. The mean aortic wall stiffness was greater for all subjects exposed to calcium-channel blockers, whether with AAA or not: 25.1 arbitrary units (95% CI, 20.0-30.2) vs 19.3 (95% CI, 18.1-20.4)(P =.002). By contrast, the mean stiffness for cases receiving ACE inhibitors was smaller than for those not receiving ACE inhibitors: 19.0 (95% CI, 13.9-24.0) vs 25.2 (95% CI, 23.0-27.4)., Conclusions: Calcium-channel blockers were an independent risk factor for the presence of an AAA and were associated with an increased arterial aortic wall stiffness. ACE inhibitors were associated with decreased stiffness and greater collagen turnover. No significant effects on the growth rate of small aneurysms were detected.