Immunohistochemical findings of juxtaglomerular cells on acute phase in two-kidney Goldblatt hypertensive rats and spontaneously hypertensive rats.

Juxtaglomerular (JG) cells on the acute phase in two-kidney Goldblatt hypertensive (2KGH) rats and spontaneously hypertensive rats (SHR) were examined immunohistochemically. JG cells in 2KGH rats and SHR were positively stained with anti-renin serum and anti-angiotensin II (A II) serum. In 2KGH rats, the number of renin and AII immunoreactive JG cells in the clipped kidneys increased throughout the observation period. The number of renin and AII immunoreactive JG cells in the unclipped kidneys was almost the same as that in control rats, although immunoreactivity of these cells was weak and they were small in size. These changes in the unclipped kidneys became obvious with the time course after operation. We did not see any changes in these cells in SHR. In 2KGH rats treated with captopril, the number of renin immunoreactive JG cells in the clipped kidneys increased, whereas that of AII immunoreactive JG cells in the bilateral kidney decreased. When captopril was administered to SHR, the number of renin immunoreactive JG cells in the bilateral kidney increased, whereas that of AII immunoreactive JG cells in the bilateral kidney decreased. These results suggested that the JG cell in the bilateral kidney was closely related to the development of hypertension in 2KGH rats, but not in SHR. The increase of renin immunoreactive JG cells in 2KGH rats and SHR treated with captopril was probably due to the removal of negative feedback inhibition of AII on JG cells.