Hormone found in the sinus gland of isopods and decapods which controls the blood sugar level. Has a secretagogue action over the amylase released from the midgut gland. May act as a stress hormone and may be involved in the control of molting and reproduction. Produced by the medulla terminalis X-organ in the eyestalks and transported to the sinus gland where they are stored and released. Present also in the ventral nervous system. Stereoinversion of L-Phe (form CHH-B-I) to D-Phe (form CHH-B-II). Belongs to the arthropod CHH/MIH/GIH/VIH hormone family.