Assuntos
Di-Hidroxifenilalanina/metabolismo , Neoplasias/metabolismo , Vitamina K/análogos & derivados , Adolescente , Adulto , Idoso , Antineoplásicos/metabolismo , Autorradiografia , Feminino , Humanos , Marcação por Isótopo , Masculino , Pessoa de Meia-Idade , Compostos Organofosforados/metabolismo , Trítio , Vitamina K/metabolismoRESUMO
It was shown on albino mice that when DOPA-3H (20 muCi/mouse) was administered before nonradioactive DOPA (1 mg/mouse) tritium accumulation in the tissue of Harding-Passi's melanoma of these mice proved to increase. Melanoma radioactivity in this experimental group was double that in the tumour tissue of the animals to which DOPA-3H alone was administered. Examination of the adenylate cyclase, phosphodiesterase activity and of the level of cAMP in melanoma of mice 2 hours after DOPA administration (1 mg/mouse) showed accumulation of cAMP and an increase in the phosphodiesterase activity; as to adenylate cyclase activity--it fell. It is suggested that DOPA realizes its effect not only as melanin precursor, but also through the cAMP system, influencing the melanogenesis enzymes activity.