Central respiratory stimulant effect of bombesin in the cat

Bombesin (0.62-6.2 nmol) was administered into the cisterna magna of chloralose-anesthetized cats while monitoring tracheal airflow with a pneumotachograph. The peptide produced dose-related increases in respiratory activity which were seen primarily as increases in tidal volume. Intravenous administration of bombesin (6.2 nmol) did not cause any respiratory effects. These results indicate that bombesin acts in the brain to stimulate respiration.