Effects of cholecystokinin on acid formation in glands and cells isolated from rabbit and rat gastric mucosa

Isolated gastric glands and isolated cells prepared from rabbit and rat wer e studied to analyse the influence of cholecystokinin octapeptide (CCK 8) o n histamine stimulated parietal cell acid formation as assessed by [C-14]am inopyrine sequestered in acid tissue compartments. In rabbit gastric glands , CCK 8 evoked 32 +/- 6% (P < 0.01) inhibition of histamine stimulated acid formation, whereas in glands prepared from rat no inhibition was recorded. Instead, CCK 8 seemed to induce a variable increase of the histamine stimu lation in rat gastric glands as the aminopyrine accumulation was increased by 110 +/- 46% (P < 0.1). Further studies on cell preparations derived from rabbit gastric mucosa revealed dual properties of CCK 8, eliciting either inhibition or stimulation of the parietal cell depending on the presence of endocrine cells. The results show that paracrine communication may be effe ctive in glandular preparations, but seems to vary depending on species. (C ) 2000 Elsevier Science Inc. All rights reserved.