Carotid sinus nerve responses and ventilatory acclimatization to hypoxia in adult rats following 2 weeks of postnatal hyperoxia

2006 ◽  
Vol 150 (2-3) ◽  
pp. 155-164 ◽  
Author(s):  
Julie M. Wenninger ◽  
E. Burt Olson ◽  
Zunyi Wang ◽  
Ingegerd M. Keith ◽  
Gordon S. Mitchell ◽  
...  
Keyword(s):  
Carotid Sinus ◽  
Carotid Sinus Nerve ◽  
Adult Rats

Adult carotid chemoafferent responses to hypoxia after 1, 2, and 4 wk of postnatal hyperoxia

2003 ◽  
Vol 95 (3) ◽  
pp. 946-952 ◽  
Author(s):  
G. E. Bisgard ◽  
E. B. Olson ◽  
Z.-Y. Wang ◽  
R. W. Bavis ◽  
D. D. Fuller ◽  
...  
Keyword(s):  
Phrenic Nerve ◽  
Carotid Sinus ◽  
Acute Hypoxia ◽  
Carotid Sinus Nerve ◽  
Newborn Rats ◽  
Adult Rats ◽  
Neural Input ◽  
Hyperoxic Exposure ◽  
Depressed Response

Exposing newborn rats to postnatal hyperoxia (60% O2) for 1-4 wk attenuates the ventilatory and phrenic nerve responses to acute hypoxia in adult rats. The goal of this research was to increase our understanding of the carotid chemoreceptor afferent neural input in this depressed response with different durations of postnatal hyperoxic exposure. Rats were exposed from a few days before birth to 1, 2, or 4 wk of 60% O2 and studied after 3-5 mo in normoxia. The rats were anesthetized with urethane. Whole carotid sinus nerve (CSN) responses to NaCN (40 μg/kg iv), 10 s of asphyxia and acute isocapnic hypoxia (arterial Po2 45 Torr) were determined. Mean CSN responses to stimuli after postnatal hyperoxia were reduced compared with controls. Responses in rats exposed to 1 wk of postnatal hyperoxia were less affected than those exposed to 2 and 4 wk of hyperoxia, which were equivalent to each other. These studies illustrate the importance of normoxia during the first 2 wk of life in development of carotid chemoreceptor afferent function.

Projections of the carotid sinus nerve to the medulla in the dog

1987 ◽  
Vol 18 (3) ◽  
pp. 437-445 ◽  
Author(s):  
Cheryl L. Chernicky ◽  
Karen L. Barnes ◽  
Carlos M. Ferrario ◽  
John P. Conomy
Keyword(s):  
Carotid Sinus ◽  
Carotid Sinus Nerve

Effect of a synthetic progestin on ventilatory response to hypoxia in anesthetized rats

1989 ◽  
Vol 67 (5) ◽  
pp. 1754-1758 ◽  
Author(s):  
H. Kimura ◽  
M. Mikami ◽  
T. Kuriyama ◽  
Y. Fukuda
Keyword(s):  
Regulatory Mechanism ◽  
Carotid Sinus ◽  
Ventilatory Response ◽  
Break Point ◽  
Male Rat ◽  
Carotid Sinus Nerve ◽  
Ventilatory Responses ◽  
Chlormadinone Acetate ◽  
Ventilatory Depression ◽  
Ventilatory Response To Hypoxia

Effects on ventilatory responses to progressive isocapnic hypoxia of a synthetic potent progestin, chlormadinone acetate (CMA), were determined in the halothane-anesthetized male rat. Ventilation during the breathing of hyperoxic gas was largely unaffected by treatment with CMA when carotid chemoreceptor afferents were kept intact. The sensitivity to hypoxia evaluated by hyperbolic regression analysis of the response curve did not differ between the control and CMA groups. The reduction of ventilation after bilateral section of the carotid sinus nerve (CSN) in hyperoxia was less severe in CMA-treated than in untreated animals. Furthermore, the CMA-treated rats showed a larger increase in ventilation during the hypoxia test and a lower PO2 break point for ventilatory depression. Inhibition of hypoxic ventilatory depression by CMA persisted even after the denervation of CSN. We conclude that exogenous progestin likely protects regulatory mechanism(s) for respiration against hypoxic depression through a stimulating action independent of carotid chemoreceptor afferents and without a change in the sensitivity of the ventilatory response to hypoxia.

Sign in / Sign up

Export Citation Format

Share Document