POMC and pituitary gland adenoma: Thus, to better define the pattern of alteration of ghrelin system components in pituitary adenomas, we developed a parallel analysis of the expression pattern of native-ghrelin, In1-ghrelin variant, GHSR1a, GHSR1b and MBOAT4 in a battery of 169 human pituitary adenomas, including GH-, ACTH- and PRL-producing adenomas and NFPAs, compared with normal pituitaries.