Area postrema mediates gastric motor response induced by apomorphine in rats

Tomoshige Koga, Motoi Kobashi, Masatoshi Mizutani, Goichi Tsukamoto, Ryuji Matsuo

Research output: Contribution to journalArticle

23 Citations (Scopus)

Abstract

The effects of apomorphine administration on the autonomic responses were investigated in rats. Distinctive gastric motor responses were observed after the intravenous administration of apomorphine (0.1 mg/kg body weight). Gastric motor responses in the distal stomach induced by apomorphine administration were classified into two types. One type involved inhibition of phasic contractions which appeared just after the administration of apomorphine. The other involved an increase in the frequency of small phasic contractions accompanied by increased gastric tone appearing with a relatively longer delay. No relaxation was observed in either the proximal or distal stomach. These gastric motor responses showed a dose-response effect to the amount of apomorphine administered (0.002-0.1 mg/kg body weight). In addition, submandibular salivary secretion was observed in response to the intravenous administration of apomorphine at a dose of 3 or 10 mg/kg body weight. Pretreatment with domperidone (1 or 2 mg/kg body weight) or the ablation of the area postrema (AP) abolished the gastric motor response and salivary secretion induced by the administration of apomorphine. In conclusion, rats showed definitive autonomic phenomena in response to the administration of apomorphine. Dopamine 2-like receptors situated in the AP mediate apomorphine-induced autonomic phenomena in rats.

Original languageEnglish
Pages (from-to)122-131
Number of pages10
JournalBrain Research
Volume960
Issue number1-2
DOIs
Publication statusPublished - Jan 17 2003

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Keywords

  • Apomorphine
  • Area postrema
  • Rat
  • Stomach
  • Vagus

ASJC Scopus subject areas

  • Neuroscience(all)
  • Molecular Biology
  • Clinical Neurology
  • Developmental Biology

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