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Rationale-Female cigarette smokers tend to show greater cessation failure compared to males. Variables that contribute to the maintenance of smoking, including stress and craving, may differentially impact male and female smokers. Novel pharmacotherapies, such as oxytocin, may attenuate stress reactivity and craving in smokers, but work in this area is limited.Objectives-This study assessed the influence of gender and oxytocin on stress reactivity, craving, and smoking in a randomized, placebo-controlled laboratory relapse paradigm.Methods-Male and female adult cigarette smokers (ages 18-45) were enrolled (women oversampled 2:1) and completed a laboratory session, in which intranasal oxytocin or placebo was administered followed by a laboratory social stress task. The role of gender and oxytocin were assessed on measures of stress reactivity, cigarette craving, latency to smoke in a resistance task, subjective responses to smoking, and ad-libitum smoking.Terms of use and reuse: academic research for non-commercial purposes, see here for full terms. http://www.springer.com/gb/openaccess/authors-rights/aam-terms-v1

Background: Continuous-flow (CF) left ventricular assist devices (LVADs) improve outcomes for patients with advanced heart failure (HF). However, the lack of a physiological pulse predisposes to side-effects including uncontrolled blood pressure (BP), and there are little data regarding the impact of CF-LVADs on BP regulation. Methods: Twelve patients (10 males, 60±11 years) with advanced heart failure completed hemodynamic assessment 2.7±4.1 months before, and 4.3±1.3 months following CF-LVAD implantation. Heart rate and systolic BP via arterial catheterization were monitored during Valsalva maneuver, spontaneous breathing, and a 0.05 Hz repetitive squat-stand maneuver to characterize cardiac baroreceptor sensitivity. Plasma norepinephrine levels were assessed during head-up tilt at supine, 30 o and 60 o . Heart rate and BP were monitored during cardiopulmonary exercise testing. Results: Cardiac baroreceptor sensitivity, determined by Valsalva as well as Fourier transformation and transfer function gain of Heart rate and systolic BP during spontaneous breathing and squat-stand maneuver, was impaired before and following LVAD implantation. Norepinephrine levels were markedly elevated pre-LVAD and improved—but remained elevated post-LVAD (supine norepinephrine pre-LVAD versus post-LVAD: 654±437 versus 323±164 pg/mL). BP increased during cardiopulmonary exercise testing post-LVAD, but the magnitude of change was modest and comparable to the changes observed during the pre-LVAD cardiopulmonary exercise testing. Conclusions: Among patients with advanced heart failure with reduced ejection fraction, CF-LVAD implantation is associated with modest improvements in autonomic tone, but persistent reductions in cardiac baroreceptor sensitivity. Exercise-induced increases in BP are blunted. These findings shed new light on mechanisms for adverse events such as stroke, and persistent reductions in functional capacity, among patients supported by CF-LVADs. Registration: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT03078972.

Purpose The purpose of this study was to determine if increased intraluminal pressure is the damaging factor which reduces flow mediated dilation (FMD) in young, healthy subjects following resistance exercise to maximal exertion. Hypothesis Attenuating the rise in brachial artery pressure during weight lifting by placing a blood pressure cuff on the upper arm prevents post-exercise impairment of brachial artery FMD in sedentary individuals. Methods Nine sedentary individuals who exercise ≤1 time/week and six exercise-trained individuals who exercise ≥3 times/week performed leg press exercise to maximal exertion on two separate occasions. During one visit a blood pressure cuff, proximal to the site of brachial artery measurement, was inflated to 100 mmHg to protect the distal vasculature from the rise in intraluminal pressure which occurs during resistance exercise. Brachial artery FMD was determined using ultrasonography before and 30 minutes after weight lifting. Results Without the protective cuff, brachial artery FMD in sedentary individuals was reduced after weight lifting (9.0 ± 1.2% pre-lift vs. 6.6 ± 0.8% post-lift; p=0.005) while in exercise-trained individuals FMD was unchanged (7.4 ± 0.7% pre-lift vs. 8.0 ± 0.9% post-lift; p=0.543). With the protective cuff, FMD no longer decreased, but rather increased in sedentary individuals (8.7 ± 1.2% pre-lift vs. 10.5 ± 1.0% post-lift, p=0.025). An increase in FMD was also seen in exercise-trained subjects when the cuff was present (6.6 ±0.7% pre-lift vs. 10.9 ±1.5% post-lift, p<0.001). Conclusion Protecting the brachial artery from exercise-induced hypertension enhances FMD in sedentary and exercise-trained individuals. These results indicate that increased intraluminal pressure in the artery contributes to the reduced FMD following heavy resistance exercise in sedentary individuals.