Measurement of regional gastroduodenal blood flow with iodo [14C]antipyrine autoradiography.

Regional blood flow was measured in the gastroduodenal area by means of iodo[14C]antipyrine autoradiography. The tracer was given intravenously over a short period of time in awake rats followed by cardiac arrest and quick freezing of stomach and duodenum. Dry autoradiography of frozen sections provide a pictorial representation of radioactivity in the different tissue layers. This could be converted to blood flow after incorporation of the time course of blood radioactivity into an operational equation. A high level of resolution was achieved, allowing delineation of blood flow compartments of small dimensions such as single villi and regions within the fundic mucosa. The value of blood flow recorded in resting conditions were in agreement with previous observations with the microspheres technique. Hypotension induced a generalized decrease in blood flow, most marked in the corpus mucosa.