The adrenal gland is one of the few organs expressing the AT2 receptor in the adult. To analyse its function in vivo, we generated transgenic rats overexpressing the mouse AT2 receptor under control of the CXCMV promoter.

Results: Angiotensin II binding levels to membranes from total adrenal homogenates were increased in two transgenic lines (line 199: Bmax 1841 fmol/mg; line 235: Bmax 1989 fmol/mg versus nontransgenic controls: Bmax 972 fmol/mg). Plasma aldosterone to renin ratio (PAC/PRC) remained unchanged in line 199 expressing the transgene in brain, heart, kidney and inner zones of the adrenal gland, but was increased in line 235 expressing the transgene additionally in the zona glomerulosa (PAC/PRC in Sprague Dawley controls: 1.05 ± 0.4; in line 199: 1.1±0.6; in line 235: 3.8±1.4; p<0.002 vrs. control and vrs. line 199). After stimulation with Angiotensin II for two weeks (300ng/kg/min; osmotic minipump) PAC was still significantly elevated in line 235 compared with Angiotensin II treated non-transgenic controls (4200±1600 vrs.2800±150; p<0.05).

Conclusion: Expression of the mouse AT2 receptor in the adrenal zona glomerulosa increases aldosterone production.