Extracellular calcium acts as a "third messenger" to regulate enzyme and alkaline secretion (original) (raw)

The regulation of enzyme and alkaline secretion in epithelial tissues is influenced by extracellular calcium, which acts as a third messenger in conjunction with intracellular calcium signaling. This paper discusses the mechanisms by which extracellular calcium fluctuations can trigger responses via Ca2+ sensors on cell surfaces, highlighting the physiological relevance of these interactions. Experimental findings demonstrate that various compounds, such as spermine, can modulate enzyme secretion and extracellular pH levels independent of intracellular calcium changes, suggesting a novel role for extracellular calcium in signaling pathways.