Peptidic delta opioid receptor agonists produce antidepressant-like effects in the forced swim test and regulate BDNF mRNA expression in rats
Torregrossa MM, Jutkiewicz EM, Mosberg HI,
Balboni G, Watson SJ, Woods JH.
Neuroscience Program, University of Michigan,
Ann Arbor, MI 48109, USA.
Brain Res. 2005 Dec 15


Systemically active, nonpeptidic delta opioid receptor agonists have been shown to produce antidepressant and anxiolytic effects in animal models in rodents. In addition, delta agonists have been shown to increase expression of brain-derived neurotrophic factor (BDNF) mRNA, an effect of some antidepressants, which may be important for the clinical efficacy of antidepressant drugs. The present study examined whether a variety of peptidic delta agonists, DPDPE, JOM-13, a systemically active derivative of DPDPE, deltorphin II, and H-Dmt-Tic-NH-CH(2)-Bid could produce convulsions and antidepressant-like effects in the forced swim test. In addition, some of these compounds were examined for their influence on BDNF mRNA expression. All four agonists dose-dependently decreased immobility in the forced swim test, indicating an antidepressant-like effect. Only JOM-13 produced convulsions at doses required for antidepressant-like effects. In addition, DPDPE increased BDNF mRNA expression, as measured by in situ hybridization, in the frontal cortex. The antidepressant-like effect of the agonists in the forced swim test and the increase in BDNF mRNA expression produced by DPDPE were blocked by the delta antagonist naltrindole. Therefore, activation of the delta receptor by centrally administered peptidic agonists and intravenously administered JOM-13 produces behavioral antidepressant-like effects without producing convulsions, and some peptidic agonists can increase BDNF mRNA expression, however, not as consistently as the systemically active nonpeptidic agonists.
Delta agonists
Learned helplessness
Enkephalinase inhibitors : RB801
Delta agonists/Parkinson's therapy
Opioids, brain stimulation and reward
Cholecystokinin and delta opioid receptors
Delta opioid receptors, emotion and motivation
Delta opioid receptor agonists as antidepressants

and further reading

Future Opioids
BLTC Research
Utopian Surgery?
The Abolitionist Project
The Hedonistic Imperative
The Reproductive Revolution
Critique of Huxley's Brave New World

The Good Drug Guide
The Good Drug Guide

The Responsible Parent's Guide
To Healthy Mood Boosters For All The Family