Abstract
Peripheral chemoreceptors in the carotid body regulate respiration, sympathetic outflow, and blood pressure in response to hypoxia. The carotid bodies play a role in the counterregulatory response to hypoglycemia in animal models and may interact with the arterial baroreflex. We hypothesized that desensitization of the carotid bodies by hyperoxia in humans would blunt hypoglycemic counterregulation and baroreflex control of blood pressure during hypoglycemia. Seven healthy adults (age 26.7 ± 0.39, BMI 25 ± 0.32, M/4, F/3) each underwent two 180 min hyperinsulinemic (2 mU/kg FFM/min), hypoglycemic (3.33 mmol/L) clamps 1 week apart, randomized to either normoxia (arterial PO2 (PaO2) 111 ± 6.3 mmHg) or hyperoxia (PaO2 345 ± 80.6 mmHg) (p < 0.05). Plasma glucose concentrations were similar during normoxia and hyperoxia at baseline and during the clamp. The glucose infusion rate was 44.2 ± 3.5% higher (p < 0.01) during hyperoxia than normoxia during the clamp. Area under the curve values (expressed as % normoxia response) for counterregulatory hormones during hypoglycemia were significantly suppressed by hyperoxia. In addition, mean blood pressure during hypoglycemia was significantly lower with hyperoxia than with normoxia (delta reduction from baseline: −5.4 ± 3.4 mmHg normoxia vs. −13.8 ± 1.9 mmHg hyperoxia, p < 0.05). The typical baroreflex-mediated rise in heart rate and sympathetic activity with lower blood pressure did not occur when the CB were silenced. These data support the idea that the carotid bodies play a role in the counterregulatory response to hypoglycemia and in baroreflex control of blood pressure in humans.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
References
Alvarez-Buylla R et al (1997) Pituitary and adrenals are required for hyperglycemic reflex initiated by stimulation of CBR with cyanide. Am J Physiol 272(1 Pt 2):R392–R399
de Campos Cruz J et al (2010) Fos expression in the NTS in response to peripheral chemoreflex activation in awake rats. Auton Neurosci 152(1–2):27–34
Downes JJ, Lambertsen CJ (1966) Dynamic characteristics of ventilatory depression in man on abrupt administration of O. J Appl Physiol 21(2):447–453
Fitzgerald R, Lahiri S (1986) Reflex responses to chemoreceptor stimulation. In: Fishman A (ed) Handbook of physiology-the respiratory system, vol 2. American Physiological Society, Bethesda, pp 313–362, Section 3, Chapter 10
Garcia-Fernandez M et al (2007) Mechanisms of low-glucose sensitivity in carotid body glomus cells. Diabetes 56(12):2893–2900
Gerich J et al (1979) Hormonal mechanisms of recovery from insulin-induced hypoglycemia in man. Am J Physiol 236(4):E380–E385
Koyama Y et al (2000) Evidence that carotid bodies play an important role in glucoregulation in vivo. Diabetes 49(9):1434–1442
Koyama Y et al (2001) Role of carotid bodies in control of the neuroendocrine response to exercise. Am J Physiol Endocrinol Metab 281(4):E742–E748
Lahiri S, DeLaney RG (1975) Relationship between carotid chemoreceptor activity and ventilation in the cat. Respir Physiol 24(3):267–286
Lecavalier L et al (1989) Contributions of gluconeogenesis and glycogenolysis during glucose counterregulation in normal humans. Am J Physiol 256(6 Pt 1):E844–E851
Pardal R, Lopez-Barneo J (2002) Low glucose-sensing cells in the carotid body. Nat Neurosci 5(3):197–198
Wehrwein EA et al (2010) Hyperoxia blunts counterregulation during hypoglycaemia in humans: possible role for the carotid bodies? J Physiol 588(Pt 22):4593–4601
Author information
Authors and Affiliations
Corresponding author
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 2012 Springer Science+Business Media Dordrecht
About this paper
Cite this paper
Wehrwein, E.A., Curry, T.B., Basu, A., Rizza, R.A., Basu, R., Joyner, M.J. (2012). Do the Carotid Bodies Modulate Hypoglycemic Counterregulation and Baroreflex Control of Blood Pressure In Humans?. In: Nurse, C., Gonzalez, C., Peers, C., Prabhakar, N. (eds) Arterial Chemoreception. Advances in Experimental Medicine and Biology, vol 758. Springer, Dordrecht. https://doi.org/10.1007/978-94-007-4584-1_18
Download citation
DOI: https://doi.org/10.1007/978-94-007-4584-1_18
Published:
Publisher Name: Springer, Dordrecht
Print ISBN: 978-94-007-4583-4
Online ISBN: 978-94-007-4584-1
eBook Packages: Biomedical and Life SciencesBiomedical and Life Sciences (R0)