Neurons of the ventrolateral preoptic nucleus (VLPO) of the hypothalamus release _______ that promotes sleep. 00:40 Biology Chapter 8 Neurons of the ventrolateral preoptic nucleus (VLPO) of the hypothalamus release _______ that promotes sleep. A. GABA B. acetylcholine C. dopamine D. histamine Answer: GABA Learn More : Share this Share on FacebookTweet on TwitterPlus on Google+