Inhibitory hormones secreted by hypothalamus are somatostatin and dopamine. Somatostatin inhibits GH, ACTH, TSH. Dopamine inhibits prolactin. GH is under both stimulatory (GHRH) and inhibitory control (Somatostatin) Prolactin is only under inhibitory control (dopamine). Note: Read the question carefully; if they ask which hormones of anterior pituitary are under inhibitory control (as in this question), answer should be both prolactin and GH. However, if they ask the question, which hormone is ONLY under inhibitory control, then answer should be only prolactin.