Cellular origin of aldosteronomas.

In the 1950s, after years of suspicion and work by many investigators regarding a potent mineralocorticoid hormone from the adrenal cortex, aldosterone was at last isolated and chemically identified [40, 41]. Soon after, Jerome Conn was the first to report [11] the clinical correlate of excessive secretion of aldosterone from a benign adrenocortical tumor manifested by hypertension and hypokalemia with the increased urinary excretion of aldosterone. This tumor is often called as aldosteronoma, and the disorder produced by it has been called primary aldosteronism by Conn. In the vast majority of patients harboring such tumors, the hypertension is cured by the resection of the tumor [12, 51], although some suggest that the hypertension may recur in a proportion of apparently cured patients [3, 36]. Thus, primary aldosteronism represents one of a few potentially curable forms of hypertension. Since aldosterone is elaborated normally by the zona glomerulosa cells of the adrenal, it has been assumed that all aldosteronomas originate from the cells of the glomerulosa zone. A clonal origin of aldosteronomas has also been suggested [28]. Some earlier and recent developments, however, indicate that functionally there may be more than one type of aldosteronomas and that their cellular origins might be different.