title: Anesthesia does not increase opioid peptides in cerebrospinal fluid of humans.
abstract: One theory of narcosis postulates that inhaled anesthetics produce general anesthesia by causing the release of endogenous opioid peptides. In the present study, however, the concentration of immunoreactive beta-endorphin-like material (eight patients) or leu-enkephalin (four patients) did not increase in cerebrospinal fluid of patients 5 min after induction of anesthesia with thiopental, 2-5 mg/kg and N2O 70%; after an additional 10 min, during which halothane was added; at 5, 15, and 60 min after surgical incision; or after 30 min in the recovery room. Therefore, any contribution of the endorphin system to the production of general anesthesia does not appear to require the release of beta-endorphin.
mesh_terms: D000698:Analgesia; D000768:Anesthesia, General; D004723:Endorphins / Q000134:cerebrospinal fluid*; D004743:Enkephalin, Leucine / Q000134:cerebrospinal fluid; D006221:Halothane; D006801:Humans; D009609:Nitrous Oxide; D013874:Thiopental; D013997:Time Factors; D001615:beta-Endorphin
chemical_list: D004723:Endorphins; D004743:Enkephalin, Leucine; D001615:beta-Endorphin; D013874:Thiopental; D009609:Nitrous Oxide; D006221:Halothane