Fig. 1. Renal corpuscle of the mouse kidney. The at'fereiit arteriole has been sectioned tangentially 

 (arrow) and appears cross sectioned (Af) in the center of the stalk (S). A granulated juxtaglomerular 

 cell is seen (J) close to the vascular pole, and a portion of the macula densa (Ma) is wedged between 

 the afferent and efferent (Ef) arterioles. The arterioles pierce through the basement membrane of the 

 Bowman's capsule (*) where a fusion of the basement membranes occurs. The glomerulus consists of 

 richly branched capillaries (C) with lymphocytes (L) and erythrocytes (R) in their limiina. The parietal 

 layer of Bowman's capsule (Pa) consists of simple squamous cells whereas the visceral layer is formed 

 by the podocytes (P) with numerous and elongated thin processes, the pedicles, which interdigitate and 

 attach at the surface of the capillaries. Between the parietal and visceral layers is the space of Bow- 

 man's capsule (B) which is continuous with the tubule (not shown). The arterioles and capillaries are 

 lined by endothelial cells (E) which rest on a continuous basement membrane. With the glomerular 

 stalk are carried in cells of mesenchjinal origin (M), with the ability to lay down connective elements 

 like collagen, elastin and basement membrane-like material. These cells have been called mesangium 

 and are on all sides surrounded by capillary basement membranes. Magnification X 1,800. 



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