The content of acetylcholine (ACh) in nerve terminals or the dorsal hippocampus was examined after intraventricular, intraseptal, or intrahippocampal administration of a variety of endorphin/corticotropin neuropeptides. beta-Lipotropin, alpha-endorphin, gamma-endorphin, alpha-melanotropin, beta-melanotropin, adrenocorticotropin-1-39 (ACTH1-39), and ACTH4-10 (1, 3, 10, or 30 micrograms each) did...

Endorphins and endorphin agonists play a crucial role in the neural modulation of mood, anxiety, pain and addiction. Recent studies have elucidated the crucial mechanism of enhancing prefrontal cortex influence and dampening limbic and sub cortical influences in depression and remission consistent with the biological profile of endorphin agonists. The historical, biological, experimental and cl...

We used beta-endorphin-deficient mice as a novel approach to confirm the physiological role that opioid peptides play in the development or regulation of the immune system. We found that mice lacking beta-endorphin possessed an enhanced immune response, measured in terms of splenocyte proliferation and interleukin (IL)-2 mRNA levels, in vitro production of the splenic macrophage inflammatory cy...

To elucidate whether or not beta-endorphin exists in plasma of normal subjects, plasma extracts obtained before and after metyrapone administration were subjected to gel exclusion chromatography, and fractions obtained were assayed by a sensitive radioimmunoassay for beta-endorphin. The basal plasma level of beta-endorphin was 5.8 +/- 1.1 pg/ml (mean +/- SE, n = 5), which rose significantly to ...

Five products of the dynorphin gene--alpha-neo-endorphin, beta-neo-endorphin, dynorphin A, dynorphin A-(1-8), and dynorphin B--were measured in various regions of rat brain and in rat spinal cord and pituitary. Specific antisera were used, supplemented by gel permeation analysis and high performance liquid chromatography, confirming the presence of dynorphin-32, dynorphin A, and dynorphin B in ...

An analog of human beta-endorphine with omission of four residues at positions 11, 14, 20, and 22 has been synthesized. This analog and other synthetic analogs with deletion of a single amino acid at position 2, 5, 6, 10, 11, 12, 13, 15, or 22 have been assayed for analgesic potency, ileal opiate activity,opiate receptor-binding activity, andimmunoreactivity. Results show that deletion of a sin...

T HE DISCOVERY, in 1973, of specific opiate receptors in the brain and, later, in the pituitary, sympathetic ganglia, kidney, liver, gastrointestinal tract, and heart suggested that there were endogenous substances that interacted specifically with these receptors.“’ Subsequently, a series of compounds that exhibited specific binding to these receptors were isolated from different tissues, incl...

Reactivity to traumatic stress varies between individuals and only a minority of those exposed to trauma develops stress-induced psychopathologies. Currently extensive effort is made to unravel the specific mechanisms predisposing to vulnerability vs. resilience to stress. We investigated in rats the role of β-endorphin metabolism in vulnerability to acute traumatic stress. Responders (showing ...

BACKGROUND Opioid peptides released from immunocytes during inflammation and stress in critically ill patients are associated with an altered immune response. Moreover, concentrations of opioid peptides are increased in peripheral blood and at the sites of inflammatory reactions. METHODS Using flow cytometric assay of whole human blood, we investigated direct effects of endogenous and synthet...