these studies included demonstration that injection of 4 x 10 ( 6 ) microspheres results in sufficient numbers of microspheres in the adrenal medulla and cortex to permit estimation of blood flow ( greater than or equal to 400 spheres/sample ) , that 15-micron spheres are almost completely entrapped in the adrenal gland ( greater than 98 % ) , that multiple injections of microspheres ( n = 5 ) do not alter blood flow , and that streaming of microspheres does not appear to occur to any significant extent in this vascular bed .
C0001629
adrenal medulla
C0001625
adrenal gland