Human corticotropin-releasing factor (hCRF) is a potent respiratory analeptic. Physiological and clinical aspects

During intravenous corticotropin-releasing factor stimulation tests we observed a deepening of the tidal volume in 35 patients. To investigate this presumed respiratory stimulation we measured respiratory parameters in 12 healthy male volunteers in a single-blind placebo-controlled trial. The intravenous 60-s infusion of 100 micrograms of human corticotropin-releasing factor induced a very potent respiratory stimulation in every subject: respiratory minute volume (mean +/- S.D.) increased by 81% from 6.319 +/- 0.577 to 11.464 +/- 1.264 liters per min (P less than 0.001), whereas there was only a slight rise in the mean respiratory rate from 12.4 +/- 3.0 to 14.7 +/- 2.7 breaths per min (P less than 0.001). Mean tidal volume increased from 531 +/- 105 to 809 +/- 175 ml (P less than 0.001). Mean end-tidal partial pressure of carbon dioxide decreased (P less than 0.001) from 40.3 +/- 1.2 to 33.4 +/- 1.2 mmHg, whereas mean end-tidal partial pressure of oxygen increased (P less than 0.001) from 93.2 +/- 5.4 to 113.5 +/- 5.4 mmHg. After 10 to 20 min both end-tidal carbon dioxide and oxygen partial pressures returned to the baseline values. The placebo had no measurable effects. We conclude that human corticotropin-releasing factor is a potent respiratory stimulant. With 100 micrograms the resting respiratory minute volume increases by 81%. These data point to the possible importance of the corticotropin-releasing factor as a useful adjunct in the management of patients with alveolar hypoventilation.