GNRH1 and adenoma: In this regard, the potential of CNFPAs to express more than one receptor for hypothalamic secretagogues and respond to them, assessed in this study by the intracellular calcium activity and RNA expression at the single cell level, is not consistent with the classical stimulus–secretion coupling model, since adenomas such as gonadotropinomas are expected to respond principally, if not only, to GnRH.