Scheme of filtration barrier (blood-urine) in the kidney. A. The endothelial cells of the glomerulus; 1. pore (fenestra). B. Glomerular basement membrane: 1. lamina rara interna 2. lamina densa 3. lamina rara externa C.<unk> s: 1. enzymatic and structural protein 2. filtration slit 3. diaphragma<unk> s have primary processes called trabeculae, which wrap around the glomerular capillaries. The trabeculae in turn have secondary processes called pedicels. Pedicels interdigitate, thereby giving rise to thin gaps called filtration slits. The slits are covered by slit diaphragms which are composed of a number of cell-surface proteins including nephrin, podocalyxin, and P-cadherin, which restrict the passage of large macromolecules such as serum albumin and gamma globulin and ensure that they remain in the bloodstream. Proteins that are required for the correct function of the slit diaphragm include nephrin, NEPH1, NEPH2, podocin, CD2AP. and FAT1. Small molecules such as water, glucose, and ionic salts are able to pass through the filtration slits and form an ultrafiltrate in the tubular fluid, which is further processed by the nephron to produce urine.<unk> s are also involved in regulation of glomerular filtration rate (GFR). When<unk> s contract, they cause closure of filtration slits. This decreases the GFR by reducing the surface area available for filtration.
Podocyte
Monocyte
Koilocyte
Agranulocyte
Prolymphocyte
Lymphoblast
Thymocyte
Plasma cell