Craig Hanke

Human Biology

Regulation of aldosterone and intracellular calcium in the adrenal zona glomerulosa cell.

My research focuses on the cellular events involved in controlling blood pressure. In order to regulate blood pressure, the body must control the excretion of water and this is done by controlling the excretion of salt. Aldosterone is a hormone is produced by the adrenal zona glomerulosa (ZG) cell that causes the kidney to absorb salt and increases blood pressure. The ZG cell can be stimulated to produce aldosterone by increasing the concentration of calcium within the cell.

Current studies in my laboratory focus on the cellular mechanisms controlling intracellular calcium release and the production of aldosterone. The research involves isolating and culturing ZG cells from fresh bovine adrenal glands obtained from Packerland packing. We then load the cells with a dye that fluoresces when bound to calcium and measure calcium concentration changes using a fluorescent microscope equipped with a high sensitivity digital camera (see top figure). Aldosterone production is typically measured in ZG cells stimulated with angiotensin II. We are currently examining the ability of cyclic ADP ribose to stimulate calcium release and aldosterone production within the ZG cell. Our most recent data indicates that indicates that blockade of cyclic ADP ribose using an antagonist (8 bromo cyclic ADP ribose) will inhibit the ability of the ZG cell to produce aldosterone (see bottom figure).

Cultured zona glomerulosa cells loaded with FLUO-3 dye during maximal calcium release