Estudio cronotoxicológico del acetato de ciproterona

Zusammenfassung

Cyproterone acetate is an antiandrogenic drug that competes with the dihydroprogesterone on the androgen-dependent tissues. The plasmatic hormone values show daily and seasonal variations. The chronobiology studies show the different biological rhythms in beings. Chronopharmacology, Chronotherapeutics and Chronotoxicology derive from Chronobiology and study the animal sensitivity and the replies to drugs and chemical or physical agents. The purpose of this work is making a careful study of the rhythmic toxicologic behaviour of cyproterone acetate. A classic LD50 study fitted to a chronobiologic model was made. Seven sets of ten mice (25 g, aprox.) were used. One of them belonged to the standard group and the other six had a time difference equal to 4 hours. Intraperitoneal single doses (1023.72 mg/kg B.W.) were administered at 10 a.m. and the mice were observed during 72 hours. A computer programme (COSINOR) was used for data processing. The results show that the cyproterone acetate toxicity undergoes a circadian rhythm. It was well fitted to a cosinoidal function (p < 0.02); acrophase, -209.70 (13 h, 59 min); MESOR, 41.7% and amplitude, 14.6%.