Intracellular vesicle, size

Figure 10 is a pictorial representation of the space between the cell and electrode surface (the drawing is not to scale) [31]. Following complete fusion of a spherical intracellular vesicle to the plasma membrane, the surface area of the vesicle creates a disk-shaped pore with a radius of 2r. The contents of the vesicle diffuse from this disk and spread at an angle, 9, until they reach the surface of the carbon fiber electrode positioned at a distance, h, away from the cell surface. The electrochemical reaction occurs at an area defined by r, which is representative of the size of each detected vesicle. This being the case, the quantity is related to the vesicle radius and the cell/electrode distance (h) by Eq. (3) [31]. 

In the segments strong immunological deposition was found throughout the tissue. Again the results indicate a slight correlation of cell size and the amount of acetyl esterase. In the small cells in the periphery of the juice vesicles, acetyl esterase is clearly intracellular (Fig 3 D,E), whereas the acetyl esterase was found on the cell walls of the large inner juice cells. This... 

Clathrin-mediated endocytosis involves the internalization of transmembrane receptor-ligand complexes stimulating the formation of a coated pit that eventually buds off the membrane to form an intracellular endocy-totic vesicle. This process is dependent on the protein clathrin that is recruited to the membrane and forms a cage-like structure around the forming pit. Internalization via clathrin-dependent pathway allows the uptake of particles approximately 120nm in size (63-65). Once internalized, the clathrin coating disassociates from the endosome to be recycled and to allow the endosome to fuse with an intracellular compartment, usually a... 

The superficial two to three cell layers of the corneal and conjunctival epithelium are the main barrier for the permeation of topically applied compounds. In this rate-limiting cell layer, the transcellular permeation is dictated by the lipophilicity of the cell membrane whereas the paracellular permeation is limited by the paracellular pore size and density. Vesicular penetration (e.g., receptor- or endocytosis-mediated) of macromolecules across surface epithelium is possible [33], However, the proposed mechanism is energy consuming (e.g., incorporation into pinocytotic vesicles and phagosomes) and thus more feasible in cell lines with abundant intracellular energy sources like corneal endothelium and RPE [34-37]. 

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