By Billy Hammond (Copyright AELS)

March 4, 2022

Vomiting

What makes you vomit?

The sensory signals to initiate vomiting come mainly from the pharynx, esophagus, stomach and small intestines. The signals are sent through sensory nerves including the vagus nerve to nuclei in the brainstem that are collectively called the “vomiting center” (area postrema).

The signals to actually vomit are sent via the V, VII, XI, X and XII cranial nerves to the upper gastrointestinal tract and via the vagal and sympathetic nerves to the lower tract, as well as through the spinal nerves to the diaphragm and abdominal muscles.

5-HT3 receptors in the brainstem make up part of the vomiting pathway, so medicines blocking them can inhibit the vomiting reflex pathway.

References:

Hall, John E.. Guyton and Hall Textbook of Medical Physiology E-Book (Guyton Physiology) . Chapter 66, Elsevier Health Sciences. Kindle Edition.

Gould, Douglas J.; Brueckner-Collins, Jennifer K.. High-Yield Neuroanatomy (High-Yield Series) . LWW. Kindle Edition.

Baron, Suzanne; Baron, Suzanne; Lee, Christoph; Lee, Christoph. Lange Pharmacology Flashcards, Fourth Edition (p. 204). McGraw-Hill Education. Kindle Edition.

嘔吐

嘔吐を開始させる信号は主に咽頭、食道 、胃、小腸 から送られる。迷走神経を含む知覚神経を通じて脳幹 の『嘔吐センター』(最後野)の神経核 に送られる。

実際に吐く動作を起こす信号は VVIIXIX XII脳神経を通じて上部消化管へ、迷走神経と交感神経で下部消化管へ、そして脊髄神経を通じて横隔膜と腹筋へ送れる。

脳幹内の5-HT3受容体は嘔吐経路には含まれているので受容体を阻止する薬品は応答反応経路が遮断できる。

参考

Hall, John E.. Guyton and Hall Textbook of Medical Physiology E-Book (Guyton Physiology) . Chapter 66, Elsevier Health Sciences. Kindle Edition.

Gould, Douglas J.; Brueckner-Collins, Jennifer K.. High-Yield Neuroanatomy (High-Yield Series) . LWW. Kindle Edition.

Baron, Suzanne; Baron, Suzanne; Lee, Christoph; Lee, Christoph. Lange Pharmacology Flashcards, Fourth Edition (p. 204). McGraw-Hill Education. Kindle Edition.

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