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Opioid Peptides: Central Nervous System

  • Raymond Dingledine

Abstract

Opium derivatives have been in medical use for at least 2000 years, possibly longer than any other class of drugs. Parenteral administration of these compounds results in a multitude of pharmacological effects mediated by the central nervous system (Jaffe and Martin, 1980). The brain regions involved in these actions have been identified in some instances by local microinjection of pmole quantities of opioids. For example, profound analgesia can be elicited by microinjection of morphine into the periaqueductal gray or nucleus reticularis paragigantocellularis, but not into other nearby regions (Yaksh and Rudy, 1978; Akaike et al., 1978). Electrographic seizure activity localized to limbic structures such as the hippocampus and amygdala can be produced by microinjection of opioids into the lateral ventrical (Henricksen et al., 1978; Snead and Bearden, 1982). A primary goal of opioid research is to understand the actions of opioids on integrative activities of the nervous system, both in terms of the circuitry involved and the ionic conductance mechanisms affected by these drugs.

Keywords

Dorsal Root Ganglion Opioid Receptor Dorsal Horn Pyramidal Cell Locus Coeruleus 
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© Plenum Press, New York 1985

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  • Raymond Dingledine

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