Teamwork, always an important concept in scientific investigations, today is indispensible, as new technology springs up almost weekly.

Nowhere is that approach more evident than at the National Institutes of Health -- the sprawling campus in Bethesda which is home to 11 separate institutes plus some of the laboratories for the National Institute of Mental Health -- technically part of the Alcohol, Drug Abuse and Mental Health Administration (ADAMHA).

Often at the NIH, these collaraborations take the form of loose networks woven between varying institutes. "The beauty of being here," says NIMH neuroscientist Joanna Hill, "is that there are all these experts, and when you need to know how to do something, there is always someone who knows how."

Take one of the groups interested in studying emotions. Anatomist Hill, pharmacologist Candace Pert and neuroscientist Birgit Zipser (a visiting researcher from the University of Maryland) are based at NIMH, where, among other things, they map receptors in the brain for opiates (the body's own brand of morphine), transferrin (the substance that transports iron in the body) and insulin (the chemicals that enable glucose to move into cells). Receptors are the sites at which these chemicals carry out their activity.

The NIMH group has also teamed with Sharon Wahl, Michael Ruff and Larry Wahl, all immunologists from the National Institute of Dental Research, to study receptors on macrophages -- white blood cells in the immune system. Their work has shown that macrophages respond to neuropeptides

Separately, Ruff and Pert have also collaborated with Claire Fraser and Craig Venter, two scientists from the National Institute of Neurological and Communicative Disorders and Stroke (NINCDS), who specialize in figuring out the molecular structure of receptors for other neuropeptides -- substances that Pert and Ruff believe are the chemicals of emotion. Adrenalin, for one, makes the heart beat faster, causes blood vessels to constrict and may depress the immune system.

Studies show that white blood cells, such as macrophages, respond to neuropeptides. "This whole interaction between the nervous system and the immune system is real strong," explains Fraser.

Fraser and her husband Venter, who is section chief of receptor biochemistry at NINCDS, moved to the NIH campus seven months ago.

"We've said that we hope we never take all the NIH resources for granted," Fraser said. "Having been on the outside, we're so aware of the wealth of resources here."