Previous studies have demonstrated that approximately 10 per cent of all individuals with hypertension have small tumors in the outer layers of the adrenal glands (the cortex), which produce too much of the hormone aldosterone, which in turn leads to hypertension. The difficulties have lied in realizing that a hypertensive individual suffers from this disorder, but also in diagnosing it. When correctly diagnosed, which is rarely the case for today’s patients, there is very effective treatment available in the form of laparoscopic adrenalectomy, or specific antihypertensive drugs directed towards the high aldosterone levels in blood.
In the present study the researchers have found a mutation of the gene for a particular calcium channel (CACNA1D), giving rise to a functionally disturbed protein in a small percentage of adrenal tumors. Previously, the same researchers have identified a potassium channel to be disturbed (published in Science 2011). Both disturbances change the electric potential in the cells, leading to increased release of aldosterone.
“The finding is important, since it further clarifies the mechanisms behind the increased aldosterone release, which will guide future production of diagnostic markers for these small tumors, as well as the design of specific drugs directed towards the changed channels”, says Per Hellman, Professor of Surgery at the Department of Surgical Sciences at Uppsala University.
The study was conducted by researchers at the endocrine surgical unit and the experimental endocrine surgical unit at the Department of Surgical Sciences at Uppsala University, in collaboration with colleagues from Yale University School of Medicine, New Haven, USA.
Read the full article, “Somatic and germline CACNA1D calcium channel mutations in aldosterone-producing adenomas and primary aldosteronism” by Lifton et al, on Nature Genetics website.
For more information, please contact Per Hellman, phone: +46 (0)18 611 4617, e-mail: Per.Hellman@surgsci.uu.se