The juxtaglomerular apparatus in a human kidney with polar artery stenosis.

Juxtaglomerular apparatuses (JGA) of a human kidney with stenosis of a polar artery from a hypertensive 18-year-old male patient were studied qualitatively and quantitatively on 2 mu thick serial sections from plastic embedded renal tissue. 11 JGA from juxtamedullary and 9 JGA from subcapsular cortical zones were photographed serially, the copies taped together and the cells and relationships within the JGA studied. On the copies the lenght of contact between the different juxtaglomerular structures and the basement membrane of the macula densa was measured. Futhermore we calculated the areas of surface contact and the macula densa basal area. In the juxtamedullary JGA affected by the polar artery stenosis all Goormaghtigh cells were transformed into epitheloid cells and the Goormaghtigh cell field was significantly larger than in the JGA of the subcapsular cortex, which obviously had been exposed to the systemic hypertension. The macula densa basal area was significantly greater in the juxtamedullary JGA than in the subcapsular JGA, but neither of these differed significantly from the macula densa in the normal JGA reported previously.