Wildauer Bücher+E-Medien Recherche-Tool

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

  • 1
    Electronic Resource
    Electronic Resource
    Psychopharmacology 96 (1988), S. 218-222 
    ISSN: 1432-2072
    Keywords: Mice ; Schedule-controlled behavior ; Tolerance ; Morphine ; Ketamine ; Ethylketazocine ; Metkephamid ; Levorphanol ; Cross-tolerance
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Key-press responding of mice was maintained under a fixed-ratio (FR) 30-response schedule of food presentation. Successive 3-min periods during which the experimental chamber was illuminated and the schedule was in effect were preceded by 10-min time-out (TO) periods during which all lights were out and responses had no scheduled consequences. Intraperitoneal (IP) injections of saline or of cumulative doses of drugs were given at the start of each TO period. Successive saline injections had little or no effect on response rates, whereas the μ-opioid agonists morphine (0.1–10.0 mg/kg) and levorphanol (0.1–3.0 mg/kg), the κ-opioid agonist ethylketazocine (0.03–3.0 mg/kg), the mixed μ-/δ-opioid agonist metkephamid (0.1–10.0 mg/kg), and the nonopioid dissociative anesthetic ketamine (1.0–100.0 mg/kg) generally produced dose-related decreases in response rates. Following chronic administration of morphine (100.0 mg/kg/6 h), tolerance developed to the effects of morphine on rates of responding. In addition, a comparable degree of cross-tolerance developed to the effects of levorphanol and metkephamid. On the other hand, there was no evidence of cross-tolerance to the effects of ethylketazocine or ketamine. These results are consistent with the evidence suggesting that different opioid agonists exert their behavioral effects through distinct classes of opioid receptors.
    Type of Medium: Electronic Resource
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...