Electrical activation and inhibition of respiration in vitro.
The present studies employed the neonatal rat rib-attached brain stem-spinal cord preparation to examine the effects of electrical stimulation of the medulla and the pons on respiratory-like activity. The investigation focused on determining whether electrical stimulation of the medulla can be used to modulate respiratory-like activity, whether electrical stimulation of the pons can inhibit respiratory-like activity, and how the preparation responds when both the medulla and the pons are stimulated simultaneously. The results suggest that: (1) stimulation of the ventromedial part of the medulla entrains the onset and the frequency of respiratory-like electromyographic (EMG) bursting most effectively and drives the respiratory rate as high as 0.4 Hz; (2) both ventromedial and ventrolateral pontine stimulation inhibited respiratory-like EMG bursting, but only ventrolateral pontine stimulation was followed by post-stimulation inhibition; (3) when the medulla and the pons were stimulated simultaneously, pontine stimulation-induced inhibition outweighed medullary stimulation-induced activation and resulted in a temporary cessation of respiratory-like EMG bursting.
Hamada
O
O
Department of Orthopaedic Surgery, Asahikawa Medical College, Hokkaido, Japan.
Garcia-Rill
E
E
Skinner
R D
RD
D000818:Animals; D000831:Animals, Newborn; D001933:Brain Stem / Q000502:physiology; D004558:Electric Stimulation; D004576:Electromyography; D066298:In Vitro Techniques; D008526:Medulla Oblongata / Q000502:physiology; D011149:Pons / Q000502:physiology; D051381:Rats; D017207:Rats, Sprague-Dawley; D012119:Respiration / Q000502:physiology*; D013116:Spinal Cord / Q000502:physiology