They are associated with long-term and short-term memory.[19] They also work in the liver to coordinate various enzymes that control blood glucose and other nutrients.[20] In bacteria, cyclic nucleotides bind to catabolite gene activator protein (CAP), which acts to increase metabolic enzymatic activity by increasing the rate of DNA transcription.[3] They also facilitate relaxation of smooth muscle cells in vascular tissue,[21] and activate cyclic CNG channels in retinal photoreceptors and olfactory sensory neurons. In addition, they potentially activate cyclic CNG channels in: pineal gland light sensitivity, sensory neurons of the vomeronasal organ (which is involved in the detection of pheromones), taste receptor cells, cellular signaling in sperm, airway epithelial cells, gonadotropin-releasing hormone (GnRH)-secreting neuronal cell line, and renal inner medullary collecting duct.[5]