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Neurotransmitters in the Nucleus Tractus Solitarius Mediating Cardiovascular Function

  • Hreday N. Sapru
Chapter

Abstract

The importance of the nucleus tractus solitarius (nTS) in the regulation of cardiovascular function has been known for a long time. However, the role of different neurotransmitters in this region in mediating cardiovascular functions is just beginning to be delineated. The carotid chemoreceptor afferents terminate predominantly in a midline area around the calamus scriptorius in the commissural subnucleus of the nTS while the baroreceptor and cardiopulmonary receptor afferents terminate in a region more rostral and lateral to the chemoreceptor projection site. There is a general consensus that glutamate is the neurotransmitter released at the terminals of baroreceptor, cardiopulmonary and chemoreceptor afferents in the nTS. However, cholinergic, GABAergic, and opioidergic mechanisms are also present in the nTS. Activation of glutamatergic and cholinergic mechanisms in the nTS elicits depressor responses while the activation of GABAergic and opioidergic mechanisms elicits pressor responses. Although, the precise physiological role of cholinergic, GABAergic, and opioidergic nTS mechanisms in regulating cardiovascular function remains to be elucidated, there is a general consensus that these mechanisms may play a neuromodulatory role in the nTS.

Key words

Blood pressure bradycardia caudal ventrolateral medullary depressor area chemoreceptor projection site depressor responses heart rate pressor responses rostral ventrolateral medullary pressor area 
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© Springer Science+Business Media New York 2004

Authors and Affiliations

  • Hreday N. Sapru
    • 1
  1. 1.UMDNJ — New Jersey Medical SchoolNewarkUSA

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