Effect of daily exposure to aromatic hydrocarbons on folicular growth en ratas

KARINA ANDREA BARREIRO; MARÍA PAULA DI YORIO; ROMINA DOLORES ARTILLO GUIDA; ALICIA GRACIELA FALETTI

Rosario, Pcia. de Santa Fe

Congreso; XLI Reunión Anual de la Sociedad Argentina de Farmacología Experimental; 2009

Sociedad Argentina de Farmacología Experimental

Polycyclic aromatic hydrocarbons produce different toxic responses in reproductive health by activating the arylhydrocarbon receptor (AhR). The aim of this project was to study the action of a repeated exposure of two AhR ligands, b-naphtoflavone (bNF) (an AhR agonist) and a-naphtoflavone (aNF) (an AhR antagonist) on follicular growth by using immature rats daily treated with different doses (0.1-50 mg/kg) of either bNF or aNF. After a 10 day-treatment, the animals were stimulated with gonadotropins (eCG/hCG) to induce ovulation and then killed 20 h after hCG administration. Serum progesterone levels (P), measured by radioimmunoassay, and the developing stages of follicles, determined by histological evaluation, were studied. At high levels, both aNF and bNF increased the number of primordial (aNF: 214%; bNF: 344%; p<0.001), primary (aNF: 76%; bNF: 136%; p<0.05), antral (aNF: 113%; bNF: 118%; p<0.001), and atretic (aNF: 58%; bNF: 39%; p<0.05) follicles. Only bNF increased the ovulatory rate by assessing the number of corpora lutea per ovary (84%; p<0.01). These effects were consistent with an increase in the serum P expressed as ng/ml (C: 24, aNF: 52, bNF: 56; p<0.01). These results demonstrate that repeated daily exposure to aromatic hydrocarbons, even after birth, can alter the primordial follicle reserve and the follicular growth in rats.