The transfer of substances and the amount that enters the fetal circulation are tightly controlled by at least four different mechanisms; simple diffusion, active transport, biotransformation through metabolic enzymes, and phagocytosis or pinocytosis
(Syme et al.
It has been reported that the ingestion of small particles by cells occurs by endocytosis or pinocytosis
for nanometersized particles (less than 150 nm).
Essentially all of the filtered Cd-MT is reabsorbed by pinocytosis
into proximal tubule cells in the renal cortex, and MT is catabolized by lysosomes, releasing the free [Cd.
In the proposed regulatory mechanism (3, 4), FcRns, predominantly localized intracellularly in endothelial cells that cover the bloodstream, capture circulating IgG and HSA taken up by fluidphase pinocytosis
, after the ligands enter acidified endosomal compartments.
human serum albumin, ferritin, and endotoxins) can be transported via pinocytosis
Cells use pinocytosis
to take up TCII hydroxocobalamin.