CO interact with intracellular [H+] with and without CO2-HCO3- in the cat carotid chemosensory discharge.
To test the hypothesis whether CO2-HCO3- buffer is essential for the expression of chemoreception and to distinguish between pHi and pHo interaction with pCO in the carotid chemosensory response, we superfused-perfused in vitro cat carotid bodies using HEPES-Tyrode's solution with and without CO2-HCO3-, and compared the responses at the same pHo in the absence and presence of light. In the absence of light, pCO (> 138 Torr) stimulated the carotid body chemoreceptors in CO2-HCO3- buffer at pHo of 7.40, whereas pCO (69-550 Torr) did not stimulate the neural discharge in HEPES buffer at the pHo of 7.4-7.1 but did so below pHo 7.1. In the presence of light, all the responses were diminished proportionately.
Osanai
S
S
Department of Physiology, University of Pennsylvania School of Medicine, Philadelphia 19104-6085, USA.
Rozanov
C
C
Mokashi
A
A
Buerk
D G
DG
Lahiri
S
S
D000818:Animals; D001639:Bicarbonates / Q000378:metabolism*; D002245:Carbon Dioxide / Q000378:metabolism*; D002248:Carbon Monoxide / Q000378:metabolism*; D002344:Carotid Body / Q000378:metabolism*; D002415:Cats; D004305:Dose-Response Relationship, Drug; D004594:Electrophysiology; D005260:Female; D006859:Hydrogen / Q000378:metabolism*; D066298:In Vitro Techniques; D008297:Male; D017494:Proton Pumps / Q000502:physiology
D001639:Bicarbonates; D017494:Proton Pumps; D002245:Carbon Dioxide; D002248:Carbon Monoxide; D006859:Hydrogen