Basal and dose‐response studies of gastric mucosal blood flow: Comparison of duodenal ulcer patients before and after highly selective vagotomy with normal volunteers

Abstract

Gastric mucosal blood flow (neutral red clearance, NRC) and acid secretion were measured before and after highly selective vagotomy (HSV). Eleven patients with duodenal ulcer were studied before and 12–21 days after HSV. Eight volunteers were also studied using the histamine‐H2‐receptor antagonists cimetidine and ranitidine. Basal secretion was collected for 40–50 minutes and pentagastrin was given in increasing doses each for 40 minutes. Data were analyzed using Wilcoxon's signed‐ranks test for paired samples and an analysis of covariance. Basal NRC was similar both for patients and for volunteers and was unaffected by HSV. There was a linear correlation between NRC and acid output. The patients with duodenal ulcer had a lower ratio of NRC to acid during pentagastrin stimulation than was found in normal subjects, but the regression line after HSV was comparable to that found for the volunteers. Although stimulated acid output was reduced by HSV, NRC was significantly higher after HSV than before. The 2 histamine‐H2‐receptor antagonists reduced both NRC and acid to a similar extent, and this could not be overcome by increasing the dose of pentagastrin. These results indicate that mucosal blood flow and acid secretion may not be unconditionally linked, although a linear relationship was always found. HSV produces an effect on blood flow that is not linked to the reduction in acid output.

Effect of proximal gastric vagotomy on human gastric blood flow evaluated by endoscopic laser doppler flowmetry

“…Intraoperative measurements with LDF before and after PGV have shown similar results along the devascularized part of the lesser curvature [17]. Using neutral red, McIsaac et al [18] found unchanged blood flow in patients 2-3 weeks after PGV, and measurements with LDF have shown similar results [17]. These findings and the results of the present study show that a normalization of the blood flow to preoperative values takes place during the weeks after the operation.…”

Gastric Stress Ulcer of the Rat: Relative Contribution of the Pyloric Sphincter, HCO^–₃ Bile Reflux and Mucosal Blood Flow

“…Knight et al [f9] concluded that the concentration of hydrogen ions secreted is proportional to blood flow, whereas, on the other hand. Me Isaac et al [21] did not find any correla tion. The argument is not convincing with regard to the relationship between GMBF and cimetidine [20], vagotomy [14] or splanchnic sympathectomy [12], The investi gations should be continued with more fre quent use of the laser Doppler interface for continuous experimental measurement of GMBF.…”

“…On the other hand, the beneficial effects obtained with NaHCO, confirm the significance of mucosal cytoprotcction against the increased secretion of hy drogen ions. Like Ritchie, we have concluded that the H2 antagonist is ineffective [4], Unanimity has not yet been achieved with regard to the relationship established be tween GMBF, acid secretion and mucosal protection [5,12,21]. Varhaug [36] found a correlation between the reduction in the acid secretion and the diminution of GMBF after devascularization [36], whereas Cheung and Lowry [5] observed a diminution of the mu cosal acid secretion despite an increase of GMBF when they administered a continuous infusion of prostaglandin E|.…”

“…and to establish the respective contributions of gastric stasis (ac tion of the pyloric sphincter), gastric acidity (intragastric infusions of NaHCOy) and bile reflux. Finally, certain authors have alleged that the vascularization of the gastric mucosa plays a major role [5,11,17,21], We there fore measured the blood flow in the gastric mucosa by a new method utilizing a laser Doppler vclocimeter [9,10,26,36].…”

Effect of Pentagastrin and Cimetidine on Gastric Blood Flow Measured by Laser Doppler Flowmetry

“…Studies with 14C aminopyrine clearance, neutral red clearance, and 9 9 m T~ clearance have shown increased blood flow after stimulation of acid secretion (6,9,10). However, questions have been raised concerning the reliability of the aminopyrine clearance technique and the use of neutral red clearance in man (22,23).…”