Detection of renin mRNA in mouse kidney and submandibular gland by hybridization with renin cDNA.

The presence of renin mRNA in a tissue is a manifestation of the expression of the renin gene by that tissue. In the present study 32P-labeled, single-stranded renin complementary DNA was used as a specific probe for the detection of renin mRNA in tissues by hybridization of their complementary base sequences. With use of the technique of hybridization histochemistry, renin cDNA probe bound strongly to sections of submandibular gland from male Quackenbush mice, a tissue which displays high androgen-dependent renin synthesis. Less was present in the female gland. In the kidney the probe localized in the cortex. A dot hybridization assay was developed to measure renin mRNA in serially diluted total RNA spotted onto nitrocellulose filters along with renin cDNA standards. From the concentration the ratio of renin mRNA between male and female submandibular gland and kidney was calculated as approx. 100:8:1:1, respectively, which is similar to the relative proportion of renin concentrations between these tissues. The present study thus provides the basis for investigations of the expression of the renin gene by tissues, particularly those with high renin biosynthetic activity.