Sex Steroids and the Serotonin Transporter

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT01065220
Recruitment Status : Completed
First Posted : February 9, 2010
Last Update Posted : January 3, 2014
Information provided by (Responsible Party):
Rupert Lanzenberger, Medical University of Vienna

Brief Summary:
The aim of this study is to prove the influence of the sex steroid hormones estrogen, progesterone and testosterone on the serotonin transporter (5-HTT) binding using positron emission tomography (PET) and the selective radioligand [11C]DASB. Specifically, the 5-HTT binding will be quantified before and after hormone therapy underwent by 10 male-to-female (MtF) and 10 female-to-male (FtM) transsexuals urging for hormone treatment. The high-level, long-term administration of opsite sex steroid hormones in transsexuals provide the unique opportunity to investigate the influence of sex steroid hormones on the serotonergic system. Since the serotonin transporter serves as a primary target molecule for antidepressant treatment, the results of the study will be of benefit for the assessment of the clinical relevance of estrogen and testosterone as modulatory and neuroactive agents.

Condition or disease Intervention/treatment Phase
Transsexualism Drug: Testolactone undecanoate Drug: Lynestrenol Drug: Cyproterone Acetate Drug: Estradiol Drug: 5-alpha reductase inhibitor Phase 4

Study Type : Interventional  (Clinical Trial)
Actual Enrollment : 32 participants
Allocation: Non-Randomized
Intervention Model: Single Group Assignment
Masking: None (Open Label)
Primary Purpose: Basic Science
Official Title: The Influence of Sex Steroid Hormones on Serotonin Transporter Binding in the Human Brain Investigated by Positron Emission Tomography
Study Start Date : February 2010
Actual Primary Completion Date : January 2014
Actual Study Completion Date : January 2014

Resource links provided by the National Library of Medicine

MedlinePlus related topics: Hormones
Drug Information available for: Serotonin
U.S. FDA Resources

Arm Intervention/treatment
Experimental: hormone treatment for MtF
  • cyproterone acetate
  • estradiol
  • alpha-5-reductase-inhibitor
Drug: Cyproterone Acetate
50mg per day
Other Name: Androcur®
Drug: Estradiol
100 microgram TTS twice a week
Other Name: Estradot®
Drug: 5-alpha reductase inhibitor
1mg daily
Other Name: Finasterid®
Experimental: hormone treatment for FtM
  • testosterone undecanoate
  • lynestrenol
Drug: Testolactone undecanoate
4ml i.m.
Other Name: Nebido®
Drug: Lynestrenol
Other Name: Orgametril®

Primary Outcome Measures :
  1. change in serotonin-transporter binding potential (BP) in predefined brain regions, measured by Positron Emission Tomography [ Time Frame: 5 months ]
    The serotonin-transporter BP will be assessed in a 90 min. dynamic PET measurement session at three timepoints: before start of hormonal therapy, after four weeks of hormonal therapy, and after 4 months of hormonal therapy

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Ages Eligible for Study:   18 Years to 55 Years   (Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • somatic health
  • no previous sex hormone medication
  • willingness to sign the written informed consent

Exclusion Criteria:

  • severe diseases
  • steroid hormone treatment within 6 months prior inclusion
  • treatment with psychotropic agents such as selective serotonin reuptake inhibitors (SSRIs)
  • any implant or stainless steel graft
  • positive urine pregnancy test in women at the screening visit at each PET day

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT01065220

Department of Psychiatry and Psychotherapy, Medical University of Vienna
Vienna, Austria, A-1090
Sponsors and Collaborators
Medical University of Vienna
Principal Investigator: Rupert Lanzenberger, MD A/Prof Medical University of Vienna

Publications automatically indexed to this study by Identifier (NCT Number):
Responsible Party: Rupert Lanzenberger, A/Prof. PD Dr., Medical University of Vienna Identifier: NCT01065220     History of Changes
Other Study ID Numbers: AP13214ONB
First Posted: February 9, 2010    Key Record Dates
Last Update Posted: January 3, 2014
Last Verified: January 2014

Keywords provided by Rupert Lanzenberger, Medical University of Vienna:
Serotonin Transporter
Hormone therapy
Gender Dysphoria

Additional relevant MeSH terms:
Polyestradiol phosphate
Cyproterone Acetate
Estradiol 3-benzoate
Estradiol 17 beta-cypionate
Estradiol valerate
5-alpha Reductase Inhibitors
Hormones, Hormone Substitutes, and Hormone Antagonists
Physiological Effects of Drugs
Contraceptive Agents
Reproductive Control Agents
Contraceptive Agents, Female
Serotonin Receptor Agonists
Serotonin Agents
Neurotransmitter Agents
Molecular Mechanisms of Pharmacological Action
Androgen Antagonists
Hormone Antagonists
Antineoplastic Agents
Contraceptive Agents, Male
Steroid Synthesis Inhibitors
Enzyme Inhibitors
Contraceptives, Oral, Synthetic
Contraceptives, Oral