The effect of anaesthesia on pentagastrin stimulated gastric acid secretion in the cat.

1. The effect of Saffan (alphaxalone and alphadolone acetate) and Nembutal (pentobarbitone) anaesthesia on gastric acid secretion stimulated by I.V. bolus injections of pentagastrin was investigated in the gastric fistula cat. The effect of Saffan anaesthesia was also tested on I.V. near-maximal and sub-maximal infusions of pentagastrin. 2. Neither anaesthetic reduced the acid secreted in response to bolus injections of pentagastrin. Increased acid secretion with the anaesthetic was noted at some doses of pentagastrin in both intact and vagotomized animals. 3. Saffan anaesthesia had no effect on near-maximal gastric acid secretion stimulated by pentagastrin 8 microgram kg-1 hr-1 but increased the response to pentagastrin 1 microgram kg-1 hr-1. 4. It is suggested that the differences in the acid secretory responses of the anaesthetized acutely prepared animal compared with the conscious animal are a consequence of the surgical procedures rather than the state of consciousness.