electron microscope radioautography of the isolated proximal tubule demonstrated that rsa-i 125 is taken up via small apical vesicles and tubular invaginations , released into large cytoplasmic vacuoles , and finally concentrated in membrane-bounded structures , some of which are acid phosphatase positive these results show that albumin is absorbed by proximal tubules and may be degraded intracellularly within lysosomes .
C0010834
cytoplasmic
C0042219
vacuoles