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The Catecholamine Metabolism in Rat Carotid Body: Is there any Efferent Regulation during Long-Term Hypercapnia ?

  • J. M. Pequignot
  • S. Hellström
  • M. Hellström

Abstract

Although hypoxia and hypercapnia are both able to excite the carotid body chemoreceptor activity, several lines of evidence suggest that these two stimuli may operate through different mechanisms (Acker, 1980; Bisgard et al., 1986; Donnelly et al., 1981; Fitzgerald et al., 1983; Mulligan and Lahiri, 1982). In acute hypoxia, dopamine (DA) is released from glomus cells and acts as a neuromodulator of the chemosensory excitation (Hanbauer and Hellström, 1978; Llados and Zapata, 1978). The two catecholamines, DA and norepinephrine (NE), stored in the carotid body are also involved in the chemoreceptor response to long-term hypoxia (Hanbauer et al., 1981; Pequignot et al., 1987). In contrast, there was no release of DA in response to acute hypercapnia (Fitzgerald et al., 1983) and the content of catecholamines in the carotid body remained unchanged after long-term exposure to hypercapnia (Hellström et al., 1989). Because hypercapnia, unlike hypoxia, may be largely sensed by central chemoreceptors, it is conceivable that the carotid chemoreceptor response to hypercapnia may be considerably altered by a potent efferent regulatory influence.

Keywords

Carotid Body Glomus Cell Peripheral Chemoreceptor Carotid Sinus Nerve Catecholamine Metabolism 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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References

  1. Acker, H., 1980, The meaning of tissue pO2 and local blood flow for the chemoreceptive process of the carotid body. Fed. Proc., 39:2641.Google Scholar
  2. Biscoe, T. J., and Sampson, S. R., 1968, Rhythmical and non-rhythmical spontaneous activity recorded from the central cut end of the sinus nerve, J. Physiol. (Lond.), 196:327.Google Scholar
  3. Bisgard, G. E., Busch, M. A., Daristotle, L., Berssenbrugge, A. D., and Forster, H. V., 1986, Carotid body hypercapnia does not elicit ventilatory acclimatization in goats, Respir. Physiol., 65:113.CrossRefGoogle Scholar
  4. Donnelly, D. F., Smith, E. J., and Dutton, R. E., 1981, Neural response of carotid chemoreceptors following dopamine blockade, J. Appl. Physiol., 50:172.Google Scholar
  5. Fitzgerald, R. S., Garger, P., Hauer, M. C., Raff, H., and Fechter, L., 1983, Effect of hypoxia and hypercapnia on catecholamine content in cat carotid body, J. Appl. Physiol., 54:1408.Google Scholar
  6. Fukuda, Y., Sato, A., and Trzebski, A., 1987, Carotid chemoreceptor discharge responses to hypoxia and hypercapnia in normotensive and spontaneously hypertensive rats. J. Auton. Nerv. Syst., 19:1.CrossRefGoogle Scholar
  7. Hanbauer, I., and Hellström, S., 1978, The regulation of dopamine and noradrenaline in the rat carotid body and its modification by denervation and by hypoxia, J. Physiol. (Lond.), 282:21.Google Scholar
  8. Hanbauer, I., Karoum, F., Hellström, S., and Lahiri, S., 1981, Effects of hypoxia lasting up to one month on catecholamine content in rat carotid body, Neuroscience, 6:81.CrossRefGoogle Scholar
  9. Hellström, S., Pequignot, J. M., and Dahlqvist, A., 1989, Catecholamines in the carotid body are unaffected by hypercapnia, Neurosci. Lett., 97:280.CrossRefGoogle Scholar
  10. Llados, F., and Zapata, P., 1978, Effects of dopamine analogues and antagonists on carotid body chemosensors in situ, J. Physiol. (Lond.), 274:487.Google Scholar
  11. Majcherczyk, S., Chruscielewski, L., and Trzebski, A., 1974, Effect of stimulation of carotid body chemoreceptors upon ganglioglomerular nerve activity and on chemoreceptor discharges in contralateral sinus nerve. Brain Res., 76:167.CrossRefGoogle Scholar
  12. Mulligan, E., and Lahiri, S., 1982, Separation of carotid body chemoreceptor responses to O2 and CO2 by oligomycin and by antimycin A, Am. J. Physiol., 242:C200.Google Scholar
  13. O’Regan, R., and Majcherczyk, S., 1982, Role of peripheral chemoreceptors and central chemosensitivity in the regulation of respiration and circulation, J. Exp. Biol., 100:23.Google Scholar
  14. Pequignot, J. M., Cottet-Emard, J. M., Dalmaz, Y., and Peyrin, L., 1987, Dopamine and norepinephrine dynamics in rat carotid bodies during long-term hypoxia, J. Auton. Nerv. Syst., 21:9.CrossRefGoogle Scholar

Copyright information

© Plenum Press, New York 1990

Authors and Affiliations

  • J. M. Pequignot
    • 1
  • S. Hellström
    • 2
  • M. Hellström
    • 2
  1. 1.UA CNRS 1196Physiologie, Faculté Médecine Grange-BlancheLyon Cédex 08France
  2. 2.Dept. of Anatomy and Clinical PhysiologyUniversity of UmeåUmeåSweden

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