Physiology of beta-endorphins. A close-up view and a review of the literature.
When an endogenous morphine, beta-endorphin was discovered ten years ago, the fact that this morphine is present in the brain and many other tissues suggested to neurobiologists that these peptide opiates play a role which goes beyond that of a simple modulator of the perception of pain. beta-endorphin is a neurohormone which is secreted by the pituitary gland and reaches all tissues present in the body by diffusion. Many laboratories have investigated variations in serum levels of beta-endorphin under widely varying physiological or pathological conditions. Many references to these studies in the literature have thus demonstrated that beta-endorphins play a role in certain behavioural patterns (stress, alcoholism), in obesity, diabetes and psychiatric diseases. In fact, the activity of beta-endorphins would appear to have an interesting role to play and are a promising feature in the treatment of cerebral aging; in this field, beta-endorphins act not only as neuroregulators of other neurotransmitting substances but also, via calcium channels, exert an effect on the walls of cerebral arterioles. In situ, the role of beta-endorphins at the ionic channel level has been studied using the patch-clamp technique. In 1991, E Neher and B Sakmann received the Nobel Medicine and Physiology Prize for this work. beta-endorphin, which may be the "missing link" between the neuron and the wall of the arteriole, must be considered as being a fundamental neurotransmitter in the same way as well-known substances such as noradrenaline, acetylcholine, serotonin, dopamine and the GABAergic system are also neurotransmitters.
Dalayeun
J F
JF
Hôpital Suisse, Issy-les-Moulineaux, France.
Norès
J M
JM
Bergal
S
S
D001519:Behavior / Q000502:physiology; D006801:Humans; D007473:Ion Channels / Q000502:physiology; D018377:Neurotransmitter Agents; D010146:Pain / Q000503:physiopathology; D001615:beta-Endorphin / Q000502:physiology*
D007473:Ion Channels; D018377:Neurotransmitter Agents; D001615:beta-Endorphin