Circadian Rhythmicity of Gastric Secretion and Cyclic 3′, 5′-Adenosine Monophosphate Contents of Gastric Mucosa in Rats

Abstract
In a correlative study the gastric acid output and cyclic 3′, 5′-adenosinc monophosphate contents of gastric mucosa were determined in rats. With respect to sex no significant differences were obtained. A concomitant diurnal rhythm was demonstrated for both acid output and cyclic AMP contents of gastric mucosa characterized by a peak at midnight and a trough at noon.