Hello

I'm not sure whether these answer your question but the authors are RG members and might be able to help further?

Holzer, P. (2015). Acid-sensing ion channels in gastrointestinal function. Neuropharmacology, 94, 72-79.

https://www.researchgate.net/publication/270650587_Acid-Sensing_Ion_Channels_in_Gastrointestinal_Function

Waldum, H. L., Hauso, Ø., & Fossmark, R. (2014). The regulation of gastric acid secretion–clinical perspectives. Acta physiologica, 210(2), 239-256.

https://www.researchgate.net/publication/258953671_The_regulation_of_gastric_acid_secretion_-_Clinical_perspectives

In the following paper, on p.49, the authors mention selective vagotomy for the treatment of gastric ulcer.

Furness, J. B., Callaghan, B. P., Rivera, L. R., & Cho, H. J. (2014). The Enteric Nervous System and Gastrointestinal Innervation: Integrated Local and Central Control Advances in Experimental Medicine and Biology 817:39-71 

https://www.researchgate.net/publication/263745155

I always associated this with gastric oesophageal reflux which gave the 'acid-reflux' symptoms and the perception of a high stomach acidity.

See p.57:

Very best wishes,

Mary

Article Acid-Sensing Ion Channels in Gastrointestinal Function

Article The regulation of gastric acid secretion – Clinical perspectives

Article The Enteric Nervous System and Gastrointestinal Innervation:...

Hello, signals from vagus nerves entail increased mucus  secretion to all mucus-secreting glands. It has the same result in epithelial lining cells. These signals push  also the stomach mucosa to secrete gastrin hormone especially in the antral part. This hormone increases secretion of highly acidic gastric juice.

Thyrotropin-releasing hormone from the medullary raphe nuclei appears to be the central excitatory mediator of vagal action in the dorsal motor nucleus. Vagal stimulation of the parietal cell occurs through M3 cholinergic receptors and via the release of histamine and gastrin from enterochromaffin-like cells and G-cells, respectively. Somatostatin exerts a tonic basal inhibition of both the parietal cell and the G-cell. Vagal stimulation suppresses somatostatin release from delta cells, thereby "disinhibiting" these cells.