Methylene blue (MB) appears to have other effects in addition to its well-known effects on mitochondria. The studies mentioned below reveal MB's abilities to antagonize estrogen's influence on prolactin, pituitary size, and dopamine levels.
http://www.ncbi.nlm.nih.gov/pubmed/10984069
„Methylene Blue (methylene blue) lowers prolactin levels in the anterior pituitary lobe and inhibits prolactin elevations following estradiol benzoate administration. The present results suggest that anterior pituitary DA(?) may play an important role in estrogen-induced anterior pituitary hyperplasia and tumor formation and that antioxidant drugs such as Methylene Blue may attenuate estrogen-induced pituitary growth. This may occur through an increase in DA levels associated with suppression of D-2 receptors on the anterior pituitary lobe. „
http://www.ncbi.nlm.nih.gov/pubmed/10984069
„We found that treatment with T3 or MB also prevented estrogen-induced (estrogen-induced) catecholaminergic inhibition and the increase in DA-2 dopamine receptors in the anterior pituitary. In contrast to T3, taking MB alone also slightly lowered weight (or maybe the density) of the anterior lobe of the pituitary gland. Blood serum levels and prolactin content increased after treatment with estradiol benzoate (EB), while Tz and CF partially attenuated prolactin hypersecretion after estrogen administration. This is consistent with the attenuation of EV-induced inhibition of the dopaminergic system by T3 and MB. CF taken in combination with EB also attenuates the EB-increased activity of adenohypophyseal NO synthase, which plays an important role in the regulation of prolactin secretion. Further studies on catecholaminergic systems, pituitary receptors, nitrergic systems, and mechanisms of intercellular signal transduction are needed to better study pituitary tumor transformation as well as to discover new approaches in the treatment of patients with this disease.“
http://www.ncbi.nlm.nih.gov/pubmed/8218149
„..male rats given estradiol benzoate in a long-acting microcrystalline suspension (1mg per rat intramuscularly twice weekly), MB 0.5% in the diet, and a combination of estradiol and MB. After three weeks, MB partially inhibited the growth of the anterior pituitary lobe caused by the effects of estradiol, and also partially inhibited the increase in cAMP content. CF did not affect the increase in GMP content nor the c AMP/cGMP ratio in the anterior pituitary, which was, however, decreased under the influence of estradiol. This decrease is not altered by MB. On the other hand, the increase in blood prolactin after estradiol intake is inhibited by CF, although the prolactin content of the anterior pituitary is not inhibited. „
