Researchers say that a brain protein called orexin A appears to prompt craving for cocaine, HealthDay News reported Feb. 15.

"We have looked at the protein orexin A, and found that it causes plasticity in an area of the brain that has been shown to be involved in reward behaviors," said study author Stephanie L. Borgland of the Ernest Gallo Clinic and Research Center at the University of California at San Francisco. Orexins are regulatory proteins produced in the lateral hypothalamus region of the brain.

The research could provide clues about the development of medications to block craving. "This gives us a better understanding of a pathway that's involved in addiction," Borgland said.

"There is plenty of evidence here to move forward the idea that orexin receptors represent novel targets for developing new medications that are intended to treat addiction," agreed Steven Shoplaw, a researcher at the Integrated Substance Abuse Programs at the University of California at Los Angeles. 

The research appears in the Feb. 16, 2006 issue of the journal Neuron. 

Borgland, S., et al. (2006). Orexin A in the VTA Is Critical for the Induction of Synaptic Plasticity and Behavioral Sensitization to Cocaine. Neuron, 49(4), 589-601.