Microsphere Measurement of Regional Intestinal Blood Supply and Cardiac Output in the Rat

Abstract

The regional blood supply to consecutive segments of the small intestine in the anaesthetized rat was investigated with a radioactive microsphere technique. A blood flow gradient with the lowest flow in the distal segments (0.85-0.89 ml/min.g) and the highest in the proximal segments (1.13-1.15 m1imin.g) was observed. Very few microspheres were found in the portal vein blood, indicating negligible arteriovenous shunting in the splanchnic area. The mean cardiac outputs in two consecutive measurements were 27.9 and 28.7 ml/min.100 g, respectively. The cardiac output and regional blood flow values were in accordance with those obtained with other techniques.

Gastric secretion, mucosal erosions and porto-systemic gastrin gradients as influenced by different degrees of stress in the rat

“…The MBF of its stomach (about 1 g) is slightly smaller than 1 ml/min. Similar values of MBF were reported with the use of the reference method (radioactive microspheres; [ 11]), and the usefulness of measuring MBF by the aminopyrine clearance was pointed out [10], respectively demonstrated also under conditions of inhibited basal secretion [8]. Comparable values for acidity, secretion of acid, pepsin, sodium under similar experimental circumstances were not known to us when writing this manuscript.…”

Central and Regional Haemodynamics During Controlled Hypotension Produced by Adenosine, Sodium Nitroprusside and Nitroglycerin

“…Direct measurements have been made with flow probes [7], the hydrogen clearance method [8] and the microsphere technique [9]. The latter method has been used for many years in our laboratory [10,11].…”

Effects of cimetidine upon gastric secretion and mucosal blood flow in the rat stressed by restraint

“…From a methodological point of view it was argued that the aminopyrine clearance [15] underestimates MBF in the dog [1]. Up to now there is no critical comparison of the former with a reference method (radioactive microspheres; [2]) in the rat, but the accuracy of the values obtained in this study by means of the 14C-aminopyrine clearance [36] without concomitant acid perfusion of the stomach is supported by those achieved with the reference method [23] and another [38] in this species, provided MBF accounts for approx. 70% of total gastric blood flow, which is generally accepted.…”