Cholecystokinin GPCR Assays
Background of Cholecystokinin (CCK)
CCK was originally found to be involved in gallbladder contraction and pancreatic secretion. Later, studies showed that CCK may be the most abundant neuropeptide in the mammalian central nervous system (CNS). Furthermore, there is evidence that reveals that CCK is also involved in the secretion and motility of the gastrointestinal tract. To date, two CCK receptors have been identified that mediate CCK: CCK1 receptors and CCK2 receptors.
Distribution and Function of CCK Receptors
CCK is released from gastroenteroendocrine cells in the upper small intestine in further response to dietary substances and binds to existing receptors to modulate various gastrointestinal target tissues. Notably, CCK1 and CCK2 receptors are closely associated with various disease pathologies, such as metabolic and gastrointestinal diseases.
Mechanism of CCK Receptors
The two receptor types differ in their relative affinities for natural ligands and their molecular structures. However, CCK receptors are involved in multiple pathways to exert their functions.
| Receptor | Gene | Mechanism | Agonists | Antagonists |
| CCK1 Receptors | CCKAR |
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| CCK2 Receptors | CCKBR |
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Assay List of Cholecystokinin Receptors
Creative Biolabs can provide a range of assays of cholecystokinin receptors. You can choose the assay in the list or contact us for more information:
Published Data
| Paper Title | Cholecystokinin (CCK) and its receptors (CCK1 and CCK2) in chickens: functional analysis and tissue expression |
| Journal | Poultry Science |
| Published | 2022 |
| Abstract | CCK is mainly distributed in the gastrointestinal tract and CNS and participates in a series of physiological responses through the activation of its receptors (CCK1 and CCK2). In contrast to mammals, the CCK gene and its receptors have been cloned in various birds. However, there are still large gaps in the knowledge of their functions and tissue expression. In this study, the researchers examined the expression of CCK and its two receptors in chicken tissues. In addition, the function of these two receptors was investigated. Combined with differences in the tissue distribution of CCK and its receptors, this study provides new insights into the physiological functions of CCK/CCKRs in birds. |
| Result |
Using three cell-based luciferase reporter systems and western blotting, this study demonstrated that cCCK-8S can efficiently activate cCCK1, while cCCK-8S and cCCK-4 are effective in activating cCCK2. RNA-seq data revealed that cCCK is abundantly expressed in the testis, ileum and brain, midbrain, cerebellum, hindbrain, and hypothalamus. Immunofluorescence results further confirmed that CCK is abundant in the hypothalamus. Furthermore, cCCK1 is highly expressed in the pancreas and expressed in various intestinal regions and the pituitary gland, whereas cCCK2 expression is mainly restricted to the brain. This article revealed the different specificities of the CCK receptor for various CCK peptides. Combined with the differences in tissue distribution of CCK and its receptors, this study provides a new basis for understanding the physiological function of CCK/CCKRs in birds.
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Fig.1. RNA-seq data showing the expression of CCK (A), CCK1 (B), and CCK2 (C) in adult chicken tissues. (Wan, 2022)
Reference
- Wan, Y.; et al. Cholecystokinin (CCK) and its receptors (CCK₁ and CCK₂) in chickens: functional analysis and tissue expression. Poultry Science. 2022; 13: 3352.
