ADCYAP1R1 and sudden infant death syndrome: In this respect, we note that a high dose of intrathecal PACAP can elevate blood pressure directly by activating PAC1 receptors on SPN innervating noradrenaline-secreting adrenal medulla chromaffin cells (Inglott et al., 2012) and that PACAP knockout mice, a proposed model of Sudden Infant Death Syndrome (SIDS) with blunted cardiorespiratory responses to hypoxia (Cummings et al., 2004), also have reduced TH expression (Arata et al., 2013).