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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
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Renin is synthesized as a large preprohormone. It is secreted by:
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The correct answer is  Active renin is formed in the secretory granules of the granular cells in the juxtaglomerular apparatus. Active renin has a half-life in the circulation of 80 min or less. Its only known function is to cleave the decapeptide angiotensin I from the amino terminal end of angiotensinogen (renin substrate). Ref: Barrett K.E., Barman S.M., Boitano S., Brooks H.L. (2012). Chapter 38. Regulation of Extracellular Fluid Composition & Volume. In K.E. Barrett, S.M. Barman, S. Boitano, H.L. Brooks (Eds), Ganong's Review of Medical Physiology, 24e.