The<unk>  is a thin sheet of small neurons located in the wall of the third ventricle, a composite structure of the hypothalamus. It functions in analgesia. It is located in the rostral, intermediate, and caudal regions of the hypothalamus. The rostral region aids in the production of both somatostatin and thyroid releasing hormone. The intermediate portion aids in production of thyroid releasing hormone, somatostatin, leptin, gastrin, and neuropeptide y. In humans and primates it also produces GnRH. Lastly the caudal region aids in sympathetic nervous system regulation, and is regarded as the rage center. The<unk>  does not have an effective blood–brain barrier. 11β-HSD2 expression turns cortisol into cortisone.
Periventricular nucleus
Arcuate nucleus 
Lentiform nucleus
Reticulotegmental nucleus
Fusiform body area
Sublingual nucleus
Ventral lateral nucleus
Medial pulvinar nucleus