The theory that alterations of dopaminergic synaptic transmission may play a role in the pathogenesis of schizophrenia is widely accepted. A more recent theory links the endorphin system to the etiology of schizophrenia. We propose that these two theories may be combined into a single model. Recent neurochemical and pharmacological findings have indicated close functional relationships between ...

Beta-endorphin and ACTH are concomitantly secreted by the pituitary in response to acute stress and both possess identical regulatory mechanisms (1). Intravenous administration of opioid antagonist naloxone (10 mg) decreased plasma ACTH levels in schizophrenic patients (2). Opioid agonist. morphine (50 mg/kg). administered intraperitoneally elevated plasma beta-endorphin immunoreactivity (3). S...

The prodromal syndrome of radiation sickness is characterized by nausea and vomiting but the pathophysiology and the treatment of this entity is largely unknown. We investigated this problem by determining the effects of ionizing radiation on gastric function with and without administration of the dopamine antagonist domperidone. We measured gastric electrical control activity (waves per minute...

one of the important changes of sport and physical activity in human beings is hormonal changes; these changes have different effects based on intensity, duration and type of training. beta endorphin (be), one of the neural system hormones, shows changes in blood plasma level by exercise. this neuropeptide plays an important role in pain relieving, well-being, mood enhancing and euphoria. the a...

Previous studies of the relationship between the endogenous opioid system and alcohol consumption have reported contradictory results. To shed light on this connection, we compared plasma concentrations of beta-endorphin, adrenocorticotropic hormone, and cortisol in 70 alcoholic persons after different periods of abstinence and a group of 80 control subjects. Plasma beta-endorphin was decreased...

It has been demonstrated that analgesia induced by physiological stress (1. 6) and electro-acupuncture (8) may be mediated through an endogenous opioid mechanism. It is also known that acute stressful stimuli cause a concomitant release of ,8-endorphin and adrenocorticotropin (ACTH) from the pituitary gland (4). Both these are peptides derived from a common precursor molecule (7) and the releas...

Behavioral synchrony has been linked to endorphin activity (Cohen et al., 2010; Sullivan and Rickers, 2013; Sullivan et al., 2014; Tarr et al., 2015, 2016; Weinstein et al., 2016). This has been called the synchrony effect. Synchrony has two dominant phases of movement; in-phase and anti-phase. The majority of research investigating synchrony's effect on endorphin activity has focused on in-pha...

Adult hippocampal neurogenesis is influenced by a variety of stimuli, including exercise, but the mechanisms by which running affects neurogenesis are not yet fully understood. Because beta-endorphin, which is released in response to exercise, increases cell proliferation in vitro, we hypothesized that it could exert a similar effect in vivo and mediate the stimulatory effects of running on neu...

Fragments of beta-endorphin and amphetamine cause similar effects in some tests of maze behavior in rats. The present study served to compare the influence of amphetamine and two beta-endorphin fragments [beta-endorphin (beta E)-(2-9) and beta E-(2-16)] on maze behavior in more detail. In Experiment I no significant effects of amphetamine and the peptides on behavioral performance in three sele...

OBJECTIVES We tested the hypothesis that psychological stress alters plasma levels of opioid peptides and that these plasma levels are related to pain perception in patients with coronary artery disease. BACKGROUND Public speaking psychological stress has previously been shown to be associated with silent ischemia. METHODS After instrumentation and a 30-min rest period, venous blood samples...