An unusual reaction to opioid blockade with naltrexone in a case of post-traumatic stress disorder.

An unusual behavioral and cardiovascular reaction was observed during opioid blockade with naltrexone in a 32-year-old male who met DSM III-R criteria for post-traumatic stress disorder (PTSD). As part of an ongoing placebo-controlled investigation of the effects of naltrexone on laboratory and ambulatory blood pressure reactivity, this participant reported experiencing feelings of rage, explosive behavior, and other unpleasant symptoms. When compared to all other subjects (N = 24), this individual showed significantly greater effects of naltrexone on blood pressure reactivity during the laboratory stressor. His ambulatory blood pressures, when compared to placebo, were significantly increased during the 24-hr period following naltrexone. The unusual behavioral and cardiovascular responses following ingestion of naltrexone suggest an important role for endogenous opioids in adjustment to stress in this case of PTSD.

Aerobic fitness and opioidergic inhibition of cardiovascular stress reactivity.

The role of endogenous opioids in aerobic fitness-induced decrements in cardiovascular stress reactivity was examined by comparing the effects of opioid antagonism with naltrexone on responses to stress in young adults with high versus low levels of aerobic fitness. Two hundred forty subjects were given an activity questionnaire and males with the highest (Fit) and lowest (Nonfit) aerobic activity profiles were recruited for maximal oxygen consumption (VO2max) treadmill testing and psychological stress testing (final sample N = 28). Heart rate and blood pressures were measured during performance on a computer-controlled arithmetic task after pretreatment with either naltrexone (Trexan, DuPont) or a placebo. During placebo challenges, Fit subjects, compared with Nonfit, showed lower heart rate reactivity during stress and lower mean arterial blood pressures immediately before and during recovery from stress. Naltrexone eliminated these reactivity differences by increasing heart rate reactivity and raising mean arterial blood pressure in Fit subjects. These data suggest that aerobic fitness is associated with enhanced opioidergic inhibition of circulatory stress reactivity. Opioidergic modulatory effects on stress reactivity may comprise an important mechanism in fitness-associated risk reduction for cardiovascular disease.

Multiple endocrine neoplasia type IIb: a description of several patients and review of the literature.

Our experience exemplifies the varied clinical presentations of patients with MEN IIb. This syndrome may be familial or sporadic, and clinical stigmata may be identifiable in infancy, particularly the characteristic facies and the appearance of ganglioneuromas. First-degree relatives of affected propositi and individuals with other stigmata of the syndrome should be screened carefully and repeatedly for both medullary thyroid carcinoma and pheochromocytoma. The availability of sensitive screening tests may permit detection of C-cell hyperplasia of the thyroid and adrenal medullary hyperplasia before the development of malignancy or hemodynamic consequences of pheochromocytoma. Early detection of these thyroid and adrenal disorders will permit early surgical intervention.