As expected, GH-releasing hormone receptor (GHRHR) and ghrelin receptor (GHSR1a) were also expressed at high levels in these somatotropinomas (100% and 92% of the cases, respectively; Fig. 3D), being GHRH-R mRNA levels significantly higher than those of GHSR1a. Here, GHRHR is linked to growth hormone-producing pituitary gland neoplasm.