Akira Yabuki — Page 2 | Search PubMed

PubMed2002

A simple method for the specific detection of Ren-1 renin.

BACKGROUND: Ren-1 and Ren-2 renin are expressed in the kidneys of all mice and in the submandibular gland of several mouse strains. The present study determined the usefulness of modified periodic acid silver-methenamine (PAM) staining for the specific detection of Ren-1 renin. METHODS: Conventional paraffin sections were prepared from kidneys of ICR, BALB/cA, C57BL/6Cr, C3H/HeN, DBA/2Cr, angiotensin II type 1a receptor gene knockout (AT1aKO) mice, Wistar rats and a human, and submandibular glands of C57BL/6Cr and DBA/2Cr mice. Sections were analyzed for the presence of renin using PAM and immunohistochemistry. PAM reactions were terminated at generally or weakly intense (weak PAM staining; W-PAM). In addition, kidneys of DBA/2Cr mice were fixed using various fixatives (formalin, PFA, PLP, Zamboni's, Bouin's, or Carnoy's) and treated using identical procedures. RESULTS: Although PAM-positive reactions were observed in juxtaglomerular (JG) cells, W-PAM reactions were particularly specific for these cells. These findings were observed in all mouse strains. Immunohistochemistry using mirror sections suggested that a W-PAM-positive reaction detected renin. This hypothesis was confirmed by the results from AT1aKO mice. Briefly, W-PAM detected an expansion of renin-positive areas in AT1aKO mice. Rat and human kidneys and mouse submandibular glands were negative for W-PAM. Levels of JG cell detection by W-PAM were similar in samples fixed in formalin, PFA, PLP, or Zamboni's. CONCLUSIONS: The present findings show that W-PAM can identify Ren-1 renin, but not Ren-2, rat or human renin. The W-PAM method is useful for the specific detection of Ren-1 renin.

Animals↗

PubMed2002

Life span and renal morphological characterization of the SAMP1//Ka mouse.

The senescence-accelerated-mouse prone 1 (SAMP1) is considered to be a model of accelerated senility and it also develops severe kidney damage. The SAMP1//Ka mouse is a specific pathogen free (SPF) subline of SAMP1. The present study examined the life span of the SAMP1//Ka mouse and morphologically investigated the kidneys of this animal at 3, 4, 5, 9, 12, 15, 18 and 24 months of age. Males survived for an average of 25 months and females for 28 months. The median lifespan was 18 months for males and 20 for females. Focal cell infiltration and thickening of the basement membrane in the glomerular capsules or tubules appeared from 4 months of age. At 12 months old, glomerular lesions with expansion of the mesangial matrix and thickening of the basement membrane as well as scar lesions in the outer cortex appeared, and amyloid was deposited in the interstitium or glomeruli from 18 months of age. Morphometrically, although the area of the kidney sections was increased at 24 months of age, the diameter of the renal corpuscles, the number of nuclei of the proximal convoluted tubules and the percentage of renal corpuscles with a cuboidal glomerular capsule did not change with age. The results of the present study indicate that the life span of the SAMP1//Ka is increased and that their age-related renal changes differ from those of the original SAMP1.

Aging↗