The effect of sympathetic nerve stimulation on acid secretion, regional blood flows and oxygen usage by stomachs of anaesthetized cats.

Abstract

SUMMARY1. Gastric acid secretion, and total gastric and mucosal blood flows (amidopyrine technique) were measured in anaesthetized cats. Oxygen contents of arterial and gastric venous blood were measured using an oximeter.2. Splanchnic nerve stimulation (10 Hz) significantly reduced the acid output and total gastric and mucosal blood flows produced in response to maximal gastrin pentapeptide infusions.3. The arterial haemoglobin concentration was significantly reduced during splanchnic nerve stimulation, and this is consistent with the hypothesis that the splanchnic nerve effect is directed against precapillary sphincters.4. During the period of inhibition, gastric oxygen consumption and acid secretion were reduced to similar degrees. There was no significant change in oxygen extraction by the stomach. 5. It remains possible that the splanchnic nerves directly inhibit the parietal cell activity.

A review: The agents and actions of sympathetic nerve and catecholamine inhibition of gastric mucosal function

“…Mucosal blood flow is consistently reduced [12,13,16,19] whether accompanied by acid secretion or not [14]. The vasodilator response to isopropylnoradrenaline is reduced by sympathetic nerve stimulation which confirms the presence of a vasoconstrictor pathway to the gastric mucosa.…”

“…Oxygen consumption decreased in parallel with acid secretion [16] and there was no change in oxygen extraction [16]. But the parietal cells may be extracting as much oxygen as possible to start with, nearly 70% [16], and it may be impossible to extract more. However, they do not [16] which may indicate an antisecretory action of the sympathetic nerves.…”

“…Oxygen consumption decreased in parallel with acid secretion [16] and there was no change in oxygen extraction [16]. Oxygen consumption decreased in parallel with acid secretion [16] and there was no change in oxygen extraction [16].…”

“…It is clear that electrical stimulation of the splanchnic nerves reduces gastric activity. Gastric oxygen consumption is also inhibited [16]. Gastric oxygen consumption is also inhibited [16].…”

“…However several groups of early workers produced contrary results [5][6][7][8][9]. This has been shown for gastric muscle activity [10][11][12], gastric acid secretion [13,14], gastric mucosal blood flow [12][13][14][15] and total blood flow [15,16]. This has been shown for gastric muscle activity [10][11][12], gastric acid secretion [13,14], gastric mucosal blood flow [12][13][14][15] and total blood flow [15,16].…”