Interrelation between gastric blood flow and HCl secretion in dogs. The basal condition and influence of secretory stimulants and vasoactive substances.

Total and mucosal blood flow in the nonsecreting stomach and the interrelation between local blood flow changes and gastric hydrochloric acid secretion as influenced by various drugs or hormones were investigated in 188 anaesthetized dogs. Substances acting on gastric acid secretion (histamine, pentagastrin, atropine and metiamide) and those showing vasoactive properties (norepinephrine, epinephrine, Hypertensin, nicotinic acid and glucagon) were used. Instillation of 0.1 N HCl solution into the stomach provided a good estimate of the mucosal blood flow of the nonsecreting stomach as measured by the aminopyrine clearance technique of Jacobson et al. Simultaneous recording of the total gastric blood flow with an electromagnetic blood flowmeter revealed the distribution of blood flowing through the mucosal and non-mucosal (submucosa-muscle) tissues of the resting stomach. During acid stimulation a shift of the gastric blood flow to the mucosa was observed, which may reach even 75--80% of the total amount of the blood supply during a given period. Metiamide entirely inhibited the gastric acid secretion induced by both histamine and pentagastrin, but did not parallelly diminish mucosal blood flow. Given during histamine infusion, glucagon strongly inhibited acid secretion while it did not decrease mucosal blood flow.