Plasma testosterone concentration following treatment with 10ρg (A), 1ηg (B) and 1µg (C) doses after 2, 4, 6, 8, 10 and 12 days of kisspeptin treatment. Testosterone concentrations remained unaltered until 4 days of treatment but decreased significantly thereafter. Values are expressed as mean ± SE (n=7). *p < 0.05, **p < 0.01.