Kampp, M., O. Lundgren and J. Sjöstrand. The distribution of intravascularly administered lipid soluble and lipid insoluble substances in the mucosa and the submucosa of the small intestine of the cat. Acta physiol. scand. 1968. 72. 469–480. The distribution of intra-arterially injected antipyrine-C14 (lipid soluble) and urea-C14 (lipid insoluble) in the mucosa and the submucosa of the cat intestine was investigated by autoradiography at various levels of total intestinal blood flow. At a “resting” flow level a comparatively low concentration of both tracers was noted in the villi five sec after the isotope administration. The difference in concentration between crypts and villi was most pronounced for antipyrine-C14. Further, it was demonstrated that the two tracers were eliminated slowly from the tips of the villi at “rest”. When the intestinal vascular bed was dilated by isopropylnoradrenaline, the concentration of the tracers immediately after the injection seemed more or less constant throughout the mucosa. The rate of wash-out from the villi of the two tracers was, furthermore, constant. Experiments were also performed at “resting” blood flow, in which the distribution of intra-arterially infused 4-iodoantipyrine (lipid soluble) and rubidium (lipid insoluble) was determined in three or four transverse sections of the villi. Results consistent with those described above were obtained. The findings suggest the existence of countercurrent exchange, particularly of lipid soluble substances, between the ascending and descending limbs of the mucosal vascular loops mainly located in the villi.
No takes yet. Share an insight, caveat, or question.
Kampp et al. (1968) studied this question.