Table 1.
Distribution and physiological or therapeutic role of the PACAP subfamily of receptors.
| Receptor | Distribution | Physiological/Therapeutic Role |
|---|---|---|
| VPAC1R | CNS [35] (cerebral cortex [36,37], hypothalamus [38], hippocampus [36,39]) | Control of circadian rhythm [38], learning, and memory [39] |
| Liver [40] | Glucose metabolism [41,42] | |
| Lung [40,43] | Asthma and COPD (relaxation of airway and vascular smooth muscles [44], anti-inflammatory effect [45,46], and regulation of mucus secretion [47]), chronic bronchitis [48] | |
| Intestine [40,49] | Peristalsis, ion transport and mucus secretion [11,12,50] | |
| Breast [40] | Cell proliferation in cancer [51,52] | |
| T-lymphocytes and macrophages (constitutively expressed) [53,54,55,56] | Immune regulation [32,33] | |
| VPAC2R | CNS [35] (thalamus [57,58,59], suprachiasmatic nucleus [29,31,57,59], dentate gyrus [59], amygdala [57]) | Schizophrenia [60,61,62], brain injury [63], control of circadian rhythm [29,30,31], processing of fear-related memory [64] |
| Smooth muscles [65] | Vasodilation (blood vessels) [66], erectile dysfunction (male reproductive system) [67] | |
| Pancreas [68] | Insulin secretion [34] | |
| Lungs [65,69] | Asthma and COPD (relaxation of airway and vascular smooth muscles [44,70], anti-inflammatory effect [45,46], and regulation of mucus secretion [47]), pulmonary arterial hypertension [71], chronic bronchitis [48] | |
| T-lymphocytes and macrophages (expressed upon cell activation) [53,54,56] | Immune regulation [72] | |
| PAC1R | CNS [35] (olfactory bulb [16,73], cerebral cortex, thalamus [73], hypothalamus [73,74], hippocampus, amygdala [73,75], substantia nigra [73], cerebellum [73] | Astrocyte proliferation [76], appetite and feeding behaviour [77,78], anxiety [79], stress response [80,81,82], control of circadian rhythm [20], post-traumatic stress disorder [83], traumatic brain injury [84], migraine [85], Alzheimer’s disease [86,87] |
| Embryonic nervous system [88,89] | Neuronal differentiation of neural progenitor and embryonic stem cells [90,91,92] | |
| Eyes (corneal endothelium [93], retina [94], lacrimal gland [95] | Maintenance of corneal endothelial barrier integrity [93] Protection against retinopathy [94,96] Stimulation of tear production [95] |
|
| Bone marrow (haematopoietic progenitor cells) [97] | Haematopoiesis [97] | |
| Adrenal medulla | Adrenal catecholamine secretion [98] | |
| Pancreas | Insulin secretion [99] | |
| Cardiac neurons [100] | Modulates excitability—stimulatory effect on CV system [100] | |
| Bladder | Urinary bladder dysfunction [101] |