1.11trastiuctural evidence for an innervation of epithelial emerochromathne cells in the guinea pig duo- denum. Ada Physiol. Seand. 24. hlorrlson, L. A, R. L. Sidman. and B. N. Fields. 1991. Direct knead of rerwirus Wan the intestinal lumen to the central rumor^ system through vagal autonomic nerve