Responses of single-unit carotid body chemoreceptors in adult rats.
1. Our goal was to describe the in situ responses in rats of single-unit carotid body chemoreceptors to changes in arterial PO2 and PCO2. We identified single-unit carotid chemoreceptor activity in male, adult Sprague-Dawley rats by their rapid responses to i.v. NaCN (20 microg) and transient (10 s) asphyxia. 2. Single-unit chemoreceptor responses to isocapnic changes in oxygenation within the arterial oxygen pressure range 34-114 mmHg were described by the power function: f(dis) = 74010(Pa,O2)-2.5; (r2 = 0.6), where f(dis) is the discharge frequency (spikes s-1), P(a,O2) is the arterial oxygen partial pressure (mmHg) and r2 is the correlation coefficient. 3. The responses to iso-oxic changes in CO2, assumed to be linear, had a slope of 0.089 spikes s-1 (mmHg Pa,CO2)-1 (r2 = 0.7). 4. We conclude that carotid body chemoreceptors in adult rats have responses to changes in Pa,O2 and Pa,CO2 similar to those of other species.
Vidruk
E H
EH
John Rankin Laboratory of Pulmonary Medicine and Department of Comparative Biosciences, University of Wisconsin, Madison, WI 53705, USA. ehvidruk@facstaff.wisc.edu
Olson
E B
EB
Ling
L
L
Mitchell
G S
GS
D000818:Animals; D001237:Asphyxia / Q000378:metabolism; D002245:Carbon Dioxide / Q000097:blood; D002344:Carotid Body / Q000166:cytology / Q000502:physiology*; D004594:Electrophysiology; D066298:In Vitro Techniques; D008297:Male; D009412:Nerve Fibers / Q000502:physiology; D009474:Neurons / Q000502:physiology*; D010100:Oxygen / Q000097:blood; D051381:Rats; D017207:Rats, Sprague-Dawley; D012966:Sodium Cyanide / Q000633:toxicity
D002245:Carbon Dioxide; D012966:Sodium Cyanide; D010100:Oxygen