NIH-funded scientists have developed a strain of mice with a built-in off switch that can selectively shut down the animals’ serotonin-producing cells, which make up a brain network controlling breathing, temperature regulation, and mood. The switch controls only the serotonin-producing cells, and does not affect any other cells in the animal’s brains or bodies. When the researchers powered down the animals’ serotonin cells, the animals failed to sufficiently step up their breathing to compensate for an increase of carbon dioxide in the air, and their body temperatures dropped to match the surrounding temperature. The finding has implications for understanding sudden infant death syndrome, or SIDS, which has been linked to low serotonin levels, and is thought to involve breathing abnormalities and problems with temperature control. The finding may also provide insight into depressive disorders, which also involve serotonin metabolism.
