Researchers from the Boston University School of Medicine and Harvard Medical School noted previous studies showed two brain chemicals, dopamine and glutamate, independently contribute to the development of cocaine addiction.

The researchers said their new findings indicate calcium channels provide critical links between dopamine and glutamate that drives the intense craving associated with cocaine addiction.

Diltiazem, one of a class of drugs known as calcium channel blockers, disrupts the connection between dopamine and glutamate formed during chronic cocaine use.

BU Professor Chris Pierce said there are no effective drug therapies for cocaine addiction, but research such as his using animal models could lead to desperately needed medications.

"The strength of this work is that it tells us something fundamental about how brain chemistry changes as cocaine addiction takes hold," said Pierce. "Importantly, our findings also suggest new strategies for developing cocaine addiction therapies, which thus far remain elusive."

The study appears in the March issue of the journal Nature Neuroscience.