[1] Bulgarian Acad Sci, Inst Biol & Immunol Reprod, Dept Neuroendocrinol, BU-1113 Sofia, Bulgaria
[2] Max Planck Inst Psychiat, Inst Clin, Dept Neuroendocrinol, D-80804 Munich, Germany
[3] Bulgarian Acad Sci, Inst Physiol, BU-1113 Sofia, Bulgaria
[4] Jenapharm GmbH & Co KG, Med Res, D-07745 Jena, Germany