These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.
Pubmed for Handhelds
PUBMED FOR HANDHELDS
Search MEDLINE/PubMed
Title: Enkephalin analogs and physical dependence. Author: Wei ET. Journal: J Pharmacol Exp Ther; 1981 Jan; 216(1):12-8. PubMed ID: 7192734. Abstract: A novel method of drug delivery, the osmotic minipump, was used to measure the ability of morphine and eight enkephalin analogs to produce physical dependence. After 3 days of morphine or peptide infusions into the rat brain, the dependent state was established and revealed by naloxone challenge; escape behavior, shaking, tachycardia and an increased respiration rate provided objective evidence of withdrawal. The minipump method required only small amounts of test materials; 6 micrograms of morphine sulfate or 0.17 microgram of FK 33,824, the most potent enkephalin analog, infused for 3 days per rat, were sufficient to induce dependence in all animals tested at these dose levels. A positive rank correlation was obtained between the short-term activities of the eight enkephalin analogs in inhibiting a motor response to a noxious stimuli and the long-term activities of the enkephalin analogs in producing physical dependence.[Abstract] [Full Text] [Related] [New Search]