Overview: Hypothalamic-Pituitary Axis Regulatory Mechanisms Hypothalamic-Pituitary Axis Regulatory Mechanisms Hypothalamus-Released Hormone Regulatory Mechanism Anterior Pituitary-Released Hormone GnRH Stimulates LH FSH CRH Stimulates ACTH GHRH Stimulates GH TRH Inhibits TSH Prolactin Somatostatin Inhibits GH TSH Dopamine Inhibits Prolactin