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Published on: March 2, 2011
Cerebrospinal fluid and behavioral changes after methyltestosterone administration: preliminary findings
R C Daly1, T P Su, P J Schmidt
1Behavioral Endocrinology Branch, National Institute of Mental Health, Bldg 10, Room 3N242, 10 Center Dr, MSC 1277, Bethesda, MD 20892-1277, USA. dalyr@intra.nimh.nih.gov
Archives of General Psychiatry
|February 15, 2001
Summary
Short-term anabolic androgenic steroid use alters brain chemistry, increasing 5-hydroxyindoleacetic acid (5-HIAA) and decreasing 3-methoxy-4-hydroxyphenylglycol (MHPG) in cerebrospinal fluid. These neurochemical changes correlate with observed behavioral alterations.
Area of Science:
- Neuroscience
- Endocrinology
- Psychiatry
Background:
- Anabolic androgenic steroid (AAS) abuse is a public health concern linked to psychiatric issues.
- The biological underpinnings of AAS-induced behavioral changes remain unclear.
Purpose of the Study:
- To investigate the neurochemical effects of methyltestosterone (MT) administration in healthy men.
- To explore relationships between cerebrospinal fluid (CSF) measures, MT levels, and behavioral changes.
Main Methods:
- 17 healthy men received escalating doses of methyltestosterone (MT) or placebo in a double-blind, crossover design.
- Cerebrospinal fluid (CSF) levels of monoamine metabolites, neurohormones, and neuropeptides were analyzed.
- Behavioral changes were assessed using visual analog scales.
Main Results:
- MT administration significantly decreased CSF 3-methoxy-4-hydroxyphenylglycol (MHPG) and increased CSF 5-hydroxyindoleacetic acid (5-HIAA).
- Increased CSF 5-HIAA levels correlated with heightened "activation" symptoms, including energy, sexual arousal, and reduced sleep.
- No significant correlations were found between behavioral changes and CSF/plasma MT levels or CSF MHPG.
Conclusions:
- Short-term AAS use impacts brain neurochemistry, altering CSF 5-HIAA and MHPG levels.
- Changes in CSF 5-HIAA are associated with the behavioral effects of AAS.
- This study did not find significant relationships between MT dosage, MT levels, and behavioral outcomes in this small sample.
