JPET xPharm- The Comprehensive Pharmacology Reference

Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]
QUICK SEARCH:   [advanced]


     

This Article
Right arrow Full Text (PDF)
Right arrow Submit a response
Right arrow Alert me when this article is cited
Right arrow Alert me when eLetters are posted
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Tseng, L. F.
Right arrow Articles by Li, C. H.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Tseng, L. F.
Right arrow Articles by Li, C. H.

beta-Endorphin: central sites of analgesia, catalepsy and body temperature changes in rats

LF Tseng, ET Wei, HH Loh and CH Li

beta-Endorphin was microinjected into rat brain in order to localize central sites associated with some of its pharmacologic effects: namely, analgesia (inhibition of the tail-flick response), catalepsy and changes in body temperature. Microinjections (1 microliter) were made bilaterally under halothane anesthesia and the effects of beta- endorphin were repeatedly assessed at 15- or 30-min intervals for 2 hr. beta-Endorphin produced analgesia and catalepsy when it was injected at low doses (ED50, 1.3 to 2.7 micrograms) into the medial preoptic area, nucleus accumbens, anterior hypothalamus and the periaqueductal gray- 4th ventricular spaces. Brain areas of intermediate sensitivities (ED50, 3.7 to 16 micrograms) were the medial thalamus, posterior hypothalamus and areas around the fasciculus retroflexus. The frontal cortex, striatum and lateral areas of the brain were relatively insensitive (ED50 greater than 17 micrograms) to the effects of beta- endorphin on analgesia and catalepsy. beta-Endorphin had complex effects on body temperature. For example, when beta-endorphin was injected into the nucleus accumbens or preoptic area, low doses (1.1-- 2.1 micrograms) produced hyperthermia; higher doses (8.5 micrograms) produced hypothermia. The brain regions in which low doses of beta- endorphin elicit pharmacologic effects correspond to the anatomic areas in which the endogenous beta-endorphin system is distributed. Similar correspondence to the endogenous enkephalin system was not obtained.

Volume 214, Issue 2, pp. 328-332, 08/01/1980
Copyright © 1980 by American Society for Pharmacology and Experimental Therapeutics




This article has been cited by other articles:


Home page
 Am. J. Physiol. Regul. Integr. Comp. Physiol.Home page
J. A. DiMicco and D. V. Zaretsky
The dorsomedial hypothalamus: a new player in thermoregulation
Am J Physiol Regulatory Integrative Comp Physiol, January 1, 2007; 292(1): R47 - R63.
[Abstract] [Full Text] [PDF]

Home page
 J. Pharmacol. Exp. Ther.Home page
L. Xin, E. B. Geller, and M. W. Adler
Body Temperature and Analgesic Effects of Selective Mu and Kappa Opioid Receptor Agonists Microdialyzed into Rat Brain
J. Pharmacol. Exp. Ther., April 1, 1997; 281(1): 499 - 507.
[Abstract] [Full Text]


Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]
All ASPET Journals Molecular Pharmacology Pharmacological Reviews
Molecular Interventions Drug Metabolism and Disposition

Copyright © 1980 by the American Society for Pharmacology and Experimental Therapeutics.