DECREASED MUSCARINIC RECEPTOR-BINDING IN THE ARCUATE NUCLEUS IN SUDDEN-INFANT-DEATH-SYNDROME

Muscarinic cholinergic activity in the human arcuate nucleus at the ve ntral medullary surface is postulated to be involved in cardiopulmonar y control, A significant decrease in [H-3]quinuclidinyl benzilate bind ing to muscarinic receptors in the arcuate nucleus is now shown to occ ur in sudden infant death syndrome (SIDS) infants, compared to infants dying acutely of known causes. In infants with chronic oxygenation ab normalities, binding is low in other nuclei, as well as in the arcuate nucleus. The binding deficit in the arcuate nucleus of SIDS infants m ight contribute to a failure of responses to cardiopulmonary challenge s during sleep.