Plays a role as a central modulator of cardiovascular and renal function and nociception. Also plays a role in energy metabolism and storage. Inhibits adrenocortical cell proliferation with minor stimulation on corticosteroid release (PubMed:20045034, PubMed:22038051). Acts as a ligand for galanin receptors GALR2 and GALR3 (By similarity). Intracerebroventricular administration of the peptide induces an increase in arterial blood pressure, a decrease in both heart rate and renal excretion and delayed natriuresis. Intraventricular administration of the peptide induces antinociceptive activity. Intraperitoneal administration of the peptide induces a reduction in food consumption and body weight. Inhibits long chain fatty acid uptake into adipocytes. Also induces contraction of muscarinic-like stomach smooth muscles (PubMed:24550067). Intracerebroventricular administration of the peptide induces a decrease in heart rate, but no change in arterial pressure, and an increase in urine flow rate. Intraventricular administration of the peptide induces antinociceptive activity (PubMed:22038051). Secreted via the classical ER/Golgi-dependent pathway into the extracellular medium largely as a full-length protein without the signal peptide, and not as a hydrolyzed and amidated peptide. Localized extracellularly surrounding the villous trophoblastic cells. Detected in the serum (By similarity). Widely expressed; predominantly expressed in epithelial cells in the skin, respiratory, digestive, urinary and reproductive systems, retina, adrenal gland and various brain regions. In the adrenal gland, expressed in parenchymal cells of the cortex and in ganglionic cells and intermingled cortical cells of the medulla. Expressed in the type I glomic cells within the carotid body (at protein level). Widely expressed. Strongly expressed in esophagus, liver, pancreas, kidney, brain, hypothalamus, thyroid and ovary. Expressed in the zona glomerulosa (ZG) and zona fasciculata/reticularis (ZF/R) of the adrenal gland. Also expressed in stomach, lung, skeletal muscle, heart, uterus, spleen, adrenal gland and testis. Weakly expressed in small intestine, thymus, urinary bladder and adenohypophysis. In the brain, is expressed in the Barrington's nucleus, with lesser amount in the ventrolateral caudal periaqueductal gray (PAG) and in the mesopontine tegmentum. Up-regulated by enucleation-induced adrenocortical regeneration (at protein level). Up-regulated by dexamethasone (DX) treatment. Down-regulated by adrenocorticotropic hormone (ACTH) treatment. Up-regulated by hypoxia in the carotid body. Belongs to the spexin family.