Test Substance Attenuates Signs of Cocaine Withdrawal in Rats

An experimental compound that selectively stimulates delta opioid receptors reduces anxiety- and depression-like behaviors that follow cessation of chronic cocaine exposure in rats. Dr. Ellen Unterwald of Temple University School of Medicine and The Rockefeller University tested the compound, SNC80, after she, Dr. Shane Perrine, and colleagues discovered that delta opioid receptors in the rat brain do not respond effectively after chronic cocaine exposure. Other researchers had linked decreased delta opioid receptor responsiveness with rodent behavior resembling human anxiety and depression.

Two FDA-approved medications, propranolol and amantadine, have also shown potential to ease these cocaine withdrawal symptoms in clinical trials. Propranolol appears to blunt anxiety by blocking the receptor for adrenaline, a hormone released during stressful situations. Amantadine seems to boost mood by increasing levels of dopamine and norepinephrine in the brain. Treatment of the anxiety and depression that frequently accompany withdrawal from cocaine is important because it reduces the rate of relapse to cocaine addiction.

Neuropharmacology 54(2):355-364, 2008. [Abstract]