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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
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Raphe nucleus, in the brain stem is responisble for the secretion of which of the following chemicals?
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The correct answer is  Raphe nucleus is a cluster of cells found in the brain stem, their main function is to secrete serotonin. Serotonin (5-hydroxytryptamine; 5-HT) is present in highest concentration in blood platelets and in the gastrointestinal tract, where it is found in the enterochromaffi n cells and the myenteric plexus. Lesser amounts are found in the brain and in the retina. Ref: Molecular and Cellular Signalling By Main Beckerman, Page 292