Pii: S0306-4522(98)00050-5
نویسندگان
چکیده
The hypothesis that the naturally occurring analgesic peptide, â-endorphin, is released in the brain in response to pain had never been directly validated. In this study, we applied a brain microdialysis method for monitoring â-endorphin release in vivo, to test this hypothesis in the brains of conscious, freely moving rats. Herein we first show that endogenous â-endorphin can be measured in vivo in the brain under physiological conditions. Upon induction of a nociceptive stimulus by injection of formalin into the hind-paws of rats, the extracellular levels of â-endorphin in their arcuate nucleus increased by 88%, corresponding to their nociceptive response. This direct evidence for the release of endogenous â-endorphin in the brain in response to nociceptive stimulus indicates a possible mechanism for organisms to cope with pain. ? 1998 IBRO. Published by Elsevier Science Ltd.
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Pii: S0306-4522(98)00353-4
D. L U P I , * t H. M. COOPER,J; A. F R O E H L I C H , * L. S T A N D F O R D , § M. A. McCALL!§ and R. G. F O S T E R * ¶ *Department of Biology, Imperial College of Science, Technology and Medicine, Prince Consort Road, London SW7 2BB, U.K. tCentro Marino Internazionale (IMC), Torregrande-Oristano, Italy ~Cerveau et Vision, I.N.S.E.R.M. U-371, Avenue Doyen Lepine, 69500 Bron, France §Departm...
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Pii: S0306-4522(98)00472-2
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