Inhibits the secretion of pituitary hormones, including that of growth hormone/somatotropin (GH1), PRL, ACTH, luteinizing hormone (LH) and TSH. Also impairs ghrelin- and GnRH-stimulated secretion of GH1 and LH; the inhibition of ghrelin-stimulated secretion of GH1 can be further increased by neuronostatin. May enhance low-glucose-induced glucagon release by pancreatic alpha cells. This effect may be mediated by binding to GPR107 and PKA activation (By similarity). May regulate cardiac contractile function (By similarity). May compromise cardiomyocyte viability. In the central nervous system, may impair memory retention and may affect hippocampal excitability. May also have anxiolytic and anorexigenic effects. May play a role in arterial pressure regulation (By similarity). May inhibit basal, but not ghrelin- or GnRH-stimulated secretion of GH1 or LH, but does not affect the release of other pituitary hormones, including PRL, ACTH, FSH or TSH. Potentiates inhibitory action of somatostatin on ghrelin-stimulated secretion of GH1, but not that on GnRH-stimulated secretion of LH (By similarity). C-terminal amidation of the neuronostatin peptide is required for its biological activity, including for the regulation of mean arterial pressure. Belongs to the somatostatin family.