The Role Of Dopamine In Methylene Blue-mediated Inhibition Of Estradiol Benzoate-induced Anterior Pi

[paymanz]

The role of dopamine in methylene blue-mediated inhibition of estradiol benzoate-induced anterior pituitary hyperplasia in rats. - PubMed - NCBI

Abstract

Recently, we demonstrated that methylene blue partially inhibited estradiol-benzoate-induced anterior pituitary hyperplasia in rats. Since central dopaminergic systems participate in the regulation of estrogen-induced anterior pituitary growth and tumor transformation, this study examined whether a 3-week treatment with methylene blue could affect anterior pituitary levels of dopamine (DA), dihydroxyphenylalanine (DOPA), and dihydroxyphenylacetic acid and dopamine (D-2) receptors in male rats. Compared to controls, methylene blue significantly decreased anterior pituitary weight, increased basal anterior pituitary DA levels, and inhibited estradiol benzoate-induced decreases in anterior pituitary DA concentrations. Furthermore, we found that methylene blue alone decreased anterior pituitary D-2 receptor number. Methylene blue given in combination with estradiol benzoate partially inhibited estradiol benzoate-induced anterior pituitary growth and estradiol benzoate-induced increases in D-2 receptor number. Estradiol benzoate-treated rats had significantly lower anterior pituitary DOPA accumulation after intraperitoneal administration of 3,4-hydroxybenzyl-hydrazine dihydrochloride (NSD-1015), an irreversible inhibitor of L-aromatic amino acid decarboxylase whereas methylene blue did not affect anterior pituitary DOPA accumulation when compared to controls. Methylene blue decreased anterior pituitary prolactin levels and inhibited increases in anterior pituitary prolactin after 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 via increases in anterior pituitary DA levels associated with down-regulation of anterior pituitary D-2 receptors.

 

[paymanz]

methylene blue alone decreased anterior pituitary D-2 receptor number

im just not sure if its a desirable effect or not.

 

[Makrosky]

im just not sure if its a desirable effect or not.

I was wondering just the same.

 

[Koveras]

im just not sure if its a desirable effect or not.

If it's increasing dopamine, as it says, the decrease in dopamine receptor density is probably an adaptive response. Similar to how using a receptor blocker tends to increase receptor density. Not sure on the net effect on dopamine signalling in this instance.

Edit: I guess it says that in the last sentence heh. This would apply to any substance that increases dopamine though.

 

[magnesiumania]

And its less important. Methylene blue is to support and repair the electron transport chain which has oxygen at the end. When this works and the brain is properly oxygenated neuronal signaling is coherent.

 

[Highserotonin90]

@magnesiumania how to reduce the sensitivity to MAO inhibition?