3 Opiate receptors: Enkephalins and endorphins

doi:10.1016/S0300-595X(83)80028-0

Clinics in Endocrinology and Metabolism

Volume 12, Issue 1, March 1983, Pages 31-56

https://doi.org/10.1016/S0300-595X(83)80028-0 Get rights and content

Summary

Opiate receptors in the central nervous system may be classified according to pharmacological, behavioural, or binding studies. Classical μ-receptors probably have β-endorphin as an endogenous ligand, and seem to be involved in the modulation of pain perception, low-frequency acupuncture analgesia, and the stimulation of prolactin, growth hormone and thyroid-stimulating hormone release. Met-enkephalin is likely to be an endogenous ligand for the δ-receptors, which predominate in the basal ganglia and limbic systems; such receptors may tonically inhibit the release of corticotrophin-releasing factor. It has been suggested that the newly-described κ-receptors may inhibit the release of vasopressin and gonadotrophin-releasing factor; dynorphin may be their endogenous ligand. Endogenous opiates controlling cardiovascular and respiratory reflexes are likely to activate μ-receptors, while high-frequency acupuncture may alleviate the symptoms of opiate withdrawal by allowing an increase in Met-enkephalin to activate δ-receptors.

In the periphery, β-endorphin is concentrated in the corticotrophs of the anterior pituitary, and is cosecreted with ACTH and related peptides. Circulating Met-enkephalin originates in the gut, sympathetic nervous system and adrenal medulla. Met-enkephalin may also be extracted from carcinoid tumours and phaeochromocytomas. Elevations in circulating Met-enkephalin may occur in certain disease states with cardiovascular and psychiatric manifestations. However, manipulation of endogenous or exogenous opiates has as yet no certain place in any clinical situation.

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3 Opiate receptors: Enkephalins and endorphins

Summary

Pain

Lancet

Life Sciences

Life Sciences

Lancet

Biochemical and Biophysical Research Communications

Life Sciences

Lancet

Lancet

Brain Research

European Journal of Pharmacology

Life Sciences

Life Sciences

Lancet

Lancet

Lancet

Lancet

Lancet

Journal of Biological Chemistry

Brain Research

Life Sciences

Lancet

Lancet

Antagonism of stimulation produced analgesia by naloxone, a narcotic antagonist

Science

Enkephalin-like material elevated in ventricular cerebrospinal fluid of pain patients after analgetic focal stimulation

Science

Circulating human pituitary proy-melanotropin enhances the adrenal response to ACTH

Nature

Stress endorphins and psychosis: a hypothesis

Enddrphins and acupuncture analgesia

Chinese Medical Journal

Opiate antagonist reverses the cardiovascular effects of inhalational anaesthesia

Nature

Intravenous naloxone in acute respiratory failure

British Medical Journal

Corticotropin, lipotropin, and β-endorphin production by a human non-pituitary tumour in culture. Evidence for a common precursor

Characterisation of lipotropin, corticotropin and β-endorphin immunoreactive materials secreted in vitro by a human pituitary adenoma responsible for a case of Nelson's syndrome

Journal of Clinical Endocrinology and Metabolism

Simultaneous assay of immunoreactive β-lipotropin, γ-lipotropin and β-endorphin in plasma of normal human subjects, patients with ACTH/lipotropin hypersecretion syndromes and patients undergoing chronic haemodialysis

Journal of Clinical Investigation

Effects of naloxone on prolactin and cortisol in normal women

Lung tumours and ACTH production

Clinical Endocrinology

Inhibition of vasopressin secretion by a Metenkephalins

Hyper-endorphin syndrome in a child with necrotising encephalomyelopathy

New England Journal of Medicine

Multiple opiate receptors: different regional distribution in the brain and differential binding of opiates and opioid peptides

Molecular Pharmacology

Dynorphin is a specific endogenous ligand of the kappa opioid receptor

Science

Endorphins and ventilatory control

New England Journal of Medicine

Opiate inhibition of peptide release from the neurohumoral terminals of hypothalamic neurones

Nature

Neuroendocrine correlates of the endorphins and enkephalins

Met-enkephalin circulates in human plasma

Nature

Increased β-endorphin but not Met-enkephalin levels in human cerebrospinal fluid after acupuncture for recurrent pain

Lancet

Enkephalin precursors in human adrenal medulla and adrenal medullary tumours

Primary structure of the human Met- and Leu-enkephalin precursor and its mRNA

Nature

Decreased content of immunoreactive enkephalin-like peptide in peripheral tissues of spontaneously hypertensive rats

Nature

β-endorphin and Met-enkephalins: their distribution, modulation by estrogens and haloperidol, and role in neuroendocrine control

Endogenous opiates block dopamine inhibition of prolactin secretion in vitro

Nature

Experimental endotoxin shock: the pathophysiological function of endorphins and treatment with opiate antagonists

Journal of Infectious Diseases