|
|
||||||||
Journal of Applied Physiology, Vol 51, Issue 1 122-130, Copyright © 1981 by American Physiological Society
ARTICLES |
M. M. Grunstein, T. A. Hazinski and M. A. Schlueter
The mechanism of ventilatory depression during hypoxia in the neonate is unknown. Since endorphins depress ventilation and their actions are antagonized by naloxone, we tested the effect of naloxone on respiration during acute hypoxia in newborn rabbits. In 27 tracheotomized unanesthetized pups, ranging in age from 1 to 15 days, ventilation (VE) was measured in a body plethysmograph. At all ages, inhalation of 5% O2 initially increased VE; thereafter VE became depressed in association with a decrease in CO2 elimination (VCO2). The time constant of VE depression increased with age. During ventilatory and VCO2 depression, saline infusion had no effect. Infusion of naloxone (4 micrograms/g body wt), however, abruptly stimulated both VE and VCO2. Since naloxone acts by competitive blockade of opiate (endorphin) receptors, these data provide evidence that 1) depression in respiration and metabolism during hypoxia is related to the action of endorphins, 2) the degree of endorphin influence decreases with age, and 3) naloxone is effective in reversing hypoxic respiratory depression provided apnea is not established.
This article has been cited by other articles:
![]() |
W. A. Janczewski and J. L. Feldman Distinct rhythm generators for inspiration and expiration in the juvenile rat J. Physiol., January 15, 2006; 570(2): 407 - 420. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. M. Robinson, H. Kwok, B. M. Adams, K. C. Peebles, and G. D. Funk Development of the ventilatory response to hypoxia in Swiss CD-1 mice J Appl Physiol, May 1, 2000; 88(5): 1907 - 1914. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |