The key difference between secretin and cholecystokinin is that the secretin is a peptide hormone produced by S cells of the duodenum and jejunum while the cholecystokinin is another peptide hormone secreted by I cells of the duodenum.
Hormones are chemicals synthesized by endocrine glands. They regulate most of the bodily functions. Moreover, different types of organs secrete different hormones. Among the different types of organs, the gastrointestinal tract is an organ that secretes hormones that are essential for the food digestion, and related functions. Different parts of the GI tract also secrete hormones. Moreover, duodenum also secretes several essential hormones. Among them, secretin and cholecystokinin are two hormones produced and secreted together when foods reach the stomach. Both hormones are peptide hormones that are responsible for regulating stomach secretions and maintaining an alkaline environment in the duodenum contents.
