8-OH-DPAT suppresses spontaneous central apneas in the C57BL/6J mouse strain

Apneas are common and prognostically relevant disorders of the central control of breathing, but pharmacological interventions are dissatisfying. The respiratory phenotype of C57BL/6J mice is characterized by the occurrence of spontaneous central apneas with laryngeal closure. In the present study we investigated the impact of the 5-HT1A receptor agonist 8-OH-DPAT on apneas in C57BL/6J mice, because of the important role of serotonin in the regulation of breathing and previous reports showing that serotonergic drugs can affect central apneas. Whole-body plethysmography in awake, unrestrained mice revealed that intraperitoneal application of 8-OH-DPAT (10 μg kg−1) decreased the occurrence of spontaneous apneas from 1.91 ± 0.25 to 1.05 ± 0.05 apneas min−1. The efficacy of 5-HT1A receptor activation was further verified in the in situ working heart–brainstem preparation. Here the apneas occurred at a frequency of 1.33 ± 0.19 min−1. Intra-arterial perfusion with 1–2 μM 8-OH-DPAT completely abolished spontaneous apneas. These results suggest that 5-HT1A receptor activation may be a potential treatment option for central apneas.