The exploration of neuroendocrine regulation of crustacean hyperglycemic hormone (CHH) on innate immunity of Litopenaeus vannamei under ammonia-N stress

•The expression and content of CHH significantly reduced after CHH RNAi under ammonia-N stress.•CHH bound to GC and then transmited the NEI signal the cGMP-PKG-CREB pathway.•CHH activated biogenic amines and ACh systems of L. vannamei under ammonia-N stress.•CHH promoted Toll3-NF-κB pathway to participate in the NEI regulation of shrimp.•The immune defense parameters of L. vannamei further reduced after CHH was silenced.