The effect of betahistine on gastric acid secretion and mucosal blood flow in conscious dogs

In 3 conscious dogs, betahistine (2-(2'-methyl aminoethyl pyridine)) (80 or 160mug kg(-1) min(-1)) increased acid secretion from Heidenhain pouches to 8.8% and 17.6% respectively of the maximal response to histamine. Betahistine also increased mucosal blood flow (radioactive aniline clearance). The ratio of mucosal blood flow to secretion was greater for betahistine than for histamine but the difference between betahistine and histamine was significant in only one of the dogs.

The gastric secretory response to insulin: an 'all-or-none' phenomenon?

Dogs were prepared with Pavlov pouches which could be perfused with saline so as to detect rapidly changes occurring in acid secretion.Dose-response studies were performed by the intravenous injection of insulin (0.06, 0.12, 0.25, 0.5, or 1.0 unit/kg). Both the magnitude of peak response and the duration of response were dose-related and both were related to the magnitude of fall in plasma glucose. These results are not consistent with an ;all-or-none' hypothesis for insulin-stimulated gastric acid secretion, but favour the alternative hypothesis that insulin provides a graded glycopenic stimulus producing a graded secretory response.

The ergonomic study of engineering drawings

This article describes an investigation of engineering-drawing comprehension. A variety of subjects was used so that results would have a wider application.

The effect of selective gastric or extragastric vagotomy on gastric secretion in conscious cats

Earlier studies in dogs showed that in animals with gastric fistulas, selective gastric vagotomy decreased maximal acid secretion in response to gastrin but not to histamine, and that in animals with Heidenhain pouches, selective extragastric vagotomy increased maximal response to gastrin but not to histamine. The present study sought to determine whether similar changes occurred in cats. In cats with gastric fistulas, selective gastric vagotomy reduced maximal response to pentagastrin and to histamine by about the same extent. In cats with Heidenhain pouches, selective extragastric vagotomy had no effect on the response to pentagastrin. It is concluded that there is a species difference between the dog and the cat regarding the effects of selective gastric and selective extragastric vagotomy on gastric acid secretion in response to gastrin. It is not yet known whether man fits the pattern of the dog or the cat.

The long-term stability of the insulin test after partial vagotomy in the dog

Five dogs were prepared with gastric fistulae, and partial vagotomy was performed by division of one vagus in the neck and a main vagal trunk in the lower thorax.

The acid secretory responses to histamine dihydrochloride (o.16 mg. per kg.-hr.), and to graded intravenous doses of insulin (0.03, 0.06, 0.12, 0.5, and 1 U. per kg.) were measured soon after vagotomy and again 6 months later.

There was no significant change in the acid response to either histamine or insulin during the 6 months after vagotomy either in timing of the peak output or in the dose of insulin required for highest peak acid output. It is concluded that no detectable reinnervation occurs in the dog in this period following gastric vagotomy.

Significance of early and late positive responses to insulin hypoglycaemia in patients with intact vagi

Insulin tests were performed on 100 subjects with duodenal ulcer who had not undergone surgery. Thirty-seven per cent had ;late' positive responses to insulin. It was suggested that a late response to insulin after surgery was not necessarily an indication of ;adequate' vagotomy. The secretory responses to insulin before operation revealed no difference in peak acid concentrations or outputs between those with early and late responses. Basal acid concentrations were higher in those with late responses, though the difference was only significant when the division between early and late responses was made at 60 minutes. The distribution of the timing of the peak responses suggested that the division into ;early' and ;late' responders was artificial.