LOCALIZATION OF RESPIRATORY NEURONS IN BRAIN-STEM RETICULAR FORMATION OF CAT UNDER VARIOUS EXPERIMENTAL CONDITIONS

Localization and discharge pattern of respiratory neurons in the pontine and the medullary reticular formation were studied in both pentobarbital anesthetized cats and in cats immobilized with Flaxedil. 1. In both preparations inspiratory, expiratory and another broader group of neurons not so clearly related to respiratory phases were scattered and intermingled throughout the medullary reticular formation. 2. Respiratory neurons in the pontine reticular formation were detected in vagotomized and immobilized cats but not in cats under pentobarbital anesthesia. 3. Expiratory neurons and another broader group of respiratory neurons were found more frequently in immobilized cats than in anesthetized cats. 4. Comparisons of discharge patterns of respiratory neurons in both preparations indicated that the activity patterns of neurons were influenced by the experimental conditions. Localization of respiratory neurons in the medulla and the pons in relation to the localization of respiratory centers are discussed. © 1969 Springer-Verlag.