Cannabinoid receptors appear to play a role in several conditions—including schizophrenia, depression, obesity, and drug abuse—but a radiolabel has not been available for imaging them in the brain. Drs. Andrew G. Horti and Dean F. Wong and colleagues at the Johns Hopkins Medical Institutions synthesized a new chemical (11C-JHU75528) for this purpose. The tracer readily entered the brains of mice and baboons and bound specifically to cannabinoid receptors (CB1), unlike candidates tested in prior research. The chemical also did not induce any noticeable side effects in the animals. The researchers have also successfully tested 11C-JHU75528 in preliminary human imaging studies and are hopeful that they will someday be able to use it to clarify the relationship between CB1 and specific aspects of drug abuse and other neurological conditions.
Journal of Nuclear Medicine 47(10):1689-1696, 2006. [Full Text (PDF, 221KB)]