[The effect of an NO-synthase inhibitor, methylene blue, on the function of certain endocrine glands].

Methylene blue is a thiazine dye, which has been used in the clinical medicine as disinfection agent and in treatment of methemoglobinemia. The recent investigations showed that this dye is able to inhibit the activation of guanylate cyclase pathway in the guanylate cyclase or in the NO-synthase level. This paper summarizes the experimentally obtained results concerning the influence of methylene blue on the hypothalamic, hypophyseal, thyroid and testicular function in rats. The possible mechanism of its influence with potential role of nitric oxide in the modulation of regulating pathways in these endocrine glands is discussed.