Neuropeptides Y are crucial for the regulation of cardiovascular processes such as blood pressure. Venom of Meiacanthus fangblennies shows a potent hypotensive bioactivity (tested on M.grammistes), but has no effect on the heart rate. Therefore, finding a neuropeptide Y sequence in M.atrodorsalis venom suggests that this protein act as a hypotensive agent (Probable). Expressed by the venom gland. Heavily expressed in the venom gland transcriptome. In contrast to venom of most venomous species, the venom of Meiacanthus fangblennies is relatively painless, when tested on mammals. While species-specific nociceptive effects are possible, this defensive venom is surprisingly multifunctional, being markedly hypotensive (via neuropeptide Y and/ or enkephalins), weakly neurotoxic (unknown components, possibly PLA2s), and perhaps also pro-inflammatory (PLA2s and/or enkephalins). The pronounced hypotensive effects induced by venom peptides seem highly likely to affect the coordination and/or swim performance of envenomed fishes and therefore likely confer a fitness advantage to the fangblenny by facilitating escape from predators. Belongs to the NPY family.