We established the transgenic medaka that enable us to observe AVT neurons by EGFP.
Onset of AVT neurons occurred in two regions of embryonic brain at different stages.
AVT somata were shown in preoptic area and the ventral hypothalamus in adult brain.
AVT fibers projected into pituitary in main, but some into other brain regions.
This fish is an intriguing model to explore AVT neuronal development and function.