TRH and hyperprolactinemia: To further determine the involvement of TCS-induced hyperprolactinemia in the down-regulation of kisspeptin-reproductive endocrine, we used a type-2 dopamine receptors agonist quinpirole (Quin), because a recent study (Nakano et al., 2010) has reported that TRH-induced PRL release is inhibited by the activation of type-2 dopamine receptors.