Effects of reversible SERCA inhibition on catecholamine exocytosis and intracellular [Ca] signaling in chromaffin cells from normotensive Wistar Kyoto rats and spontaneously hypertensive rats.

Intracellular Ca ([Ca]i) signaling and catecholamine (CA) exocytosis from adrenal chromaffin cells (CCs) differ between mammalian species. These differences partly result from the different contributions of Ca-induced Ca-release (CICR) from internal stores, which boosts intracellular Ca signals. Transient inhibition of the sarcoendoplasmic reticulum (SERCA) Ca pump with cyclopiazonic acid (CPA) reduces CICR.

Calcium Imaging and Amperometric Recording in Cultured Chromaffin Cells and Adrenal Slices from Normotensive, Wistar Kyoto Rats and Spontaneously Hypertensive Rats.

The spontaneously hypertensive rat (SHR) is a model widely used to investigate the causal mechanisms of essential hypertension. The enhanced catecholamine (CA) release reported in adrenal glands from adult SHRs raised considerable interest for its possible implication in the genesis of hypertension. The use of powerful techniques such as calcium imaging, electrophysiology, and single-cell amperometry to monitor in real time the key steps in CA secretion has allowed a better understanding of the role of chromaffin cells (CC) in the pathophysiology of hypertension, although several questions remain.