What are the principal physiologic stimuli that regulate acid secretion from the proton pump?

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Explanation:  Parietal cells receive messages from several sources, which tell them to increase or decrease acid production. These cells contain receptors for the hormone gastrin, which is a principal physiologic stimulus that regulates acid secretion from the proton pump.
Parietal cells receive messages from several sources, which tell them to increase or decrease acid production. These cells contain receptors for histamine (H2), which is a principal physiologic stimulus that regulates acid secretion from the proton pump.
Parietal cells receive messages from several sources, which tell them to increase or decrease acid production. These cells contain receptors for the neurotransmitter acetylcholine, which is a principal physiologic stimulus that regulates acid secretion from the proton pump.

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