Key result
Aldosterone-producing adenoma cells show ~34% lower resting intracellular calcium versus normal adjacent adrenal cells.
Why the study?
Knowledge of intracellular calcium dynamics underlying aldosterone excess in primary aldosteronism is lacking due to difficulty obtaining aldosterone-producing adenoma cells ex vivo.
Does Angiotensin II stimulation alter intracellular calcium dynamics differently in aldosterone-producing adenoma cells compared to normal adjacent adrenal cortex cells?
Does Angiotensin II stimulation alter intracellular calcium dynamics differently in aldosterone-producing adenoma cells compared to normal adjacent adrenal cortex cells?
Aldosterone-producing adenoma cells exhibit lower resting intracellular calcium levels but more marked oscillatory responses to Angiotensin II stimulation compared to normal adrenal cortex cells, potentially underlying aldosterone excess in primary aldosteronism.
Provides mechanistic insights into PA; leaves open whether calcium modulation improves clinical outcomes.
Background Intracellular calcium [Ca 2+ ] i is pivotal in driving aldosterone secretion. However, knowledge of the [Ca 2+ ] i dynamics underlying aldosterone excess in primary aldosteronism (PA), the most common form of endocrine hypertension, is lacking due to the difficulty of obtaining aldosterone-producing adenoma (APA) cells ex vivo. Methods We used the Ca 2+ -sensitive Fura-2 dye and live confocal microscopy to investigate variations in [Ca 2+ ] i under basal conditions and after angiotensin II (Ang II) stimulation in primary aldosterone-producing CD56+ cells, immunomagnetically isolated ex vivo from surgically treated PA patients. Results We found that the resting [Ca 2+ ] i levels were consistently and markedly lower in APA cells (n = 14, 0.53; IQR: 0.33 - 0.79) compared with paired cells from the normal adjacent adrenal cortex (AAC) (n = 14, 0.80; IQR: 0.65 - 0.90, p = 0.021). While both cell types exhibited similar spontaneous oscillations, Ang II [1 nM] stimulation increased the number of cells exhibiting [Ca 2+ ] i oscillations (p = 0.004) and induced a higher frequency of oscillations (p=0.002) in APA than in AAC. Conclusion This study demonstrates prominent differences between APA and AAC cells in [Ca 2+ ] i dynamics, with more marked oscillatory responses upon Ang II stimulation. These differences may underpin the increased aldosterone production, a hallmark of human PA.
No takes yet. Share an insight, caveat, or question.
Ajjour et al. (2026) studied Primary aldosteronism (n=14). Aldosterone-producing adenoma (APA) cells vs. Normal adjacent adrenal cortex (AAC) cells was evaluated on Resting intracellular calcium [Ca2+]i levels (p=0.021). Resting intracellular calcium levels were significantly lower in aldosterone-producing adenoma cells compared with normal adjacent adrenal cortex cells (0.53 vs 0.80, p=0.021).
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: