PMID- 15458727 OWN - NLM STAT- MEDLINE DCOM- 20050127 LR - 20151119 IS - 1570-0232 (Print) IS - 1570-0232 (Linking) VI - 811 IP - 1 DP - 2004 Nov 5 TI - 3-Methoxytyramine as an indicator of dopaminergic manipulation in the equine athlete. PG - 93-101 AB - The influence of sampling variables on the concentration of the dopamine metabolites 3-methoxytyramine (3MT), dihydroxyphenylacetic acid (DOPAC) and homovanilic acid (HVA) was examined in equine urine. A logarithmic transformation of the data for all horses gave distribution which approximated the normal distributions for each metabolite. The mean urinary concentration of 3 MT in horses was 214 ng/mL and the application of a threshold with a probability of 1 in 10,000 gave an actionable level of 4 microg/mL. Environmental variables were not forensically significant in determining the population distribution. HVA was not found to be a reliable indicator of dopamine or levodopa administration. FAU - Wynne, Paul M AU - Wynne PM AD - Racing Analytical Services Limited, 400 Epsom Road, Flemington, Vic. 3031, Australia. pwynne@sge.com FAU - Vine, John H AU - Vine JH FAU - Amiet, R Gary AU - Amiet RG LA - eng PT - Journal Article PT - Research Support, Non-U.S. Gov't PL - Netherlands TA - J Chromatogr B Analyt Technol Biomed Life Sci JT - Journal of chromatography. B, Analytical technologies in the biomedical and life sciences JID - 101139554 RN - JCH2767EDP (3-methoxytyramine) RN - VTD58H1Z2X (Dopamine) SB - IM MH - Animals MH - Dopamine/*administration & dosage/*analogs & derivatives/*urine MH - *Doping in Sports MH - Horses EDAT- 2004/10/02 05:00 MHDA- 2005/01/28 09:00 CRDT- 2004/10/02 05:00 PHST- 2003/11/20 00:00 [received] PHST- 2004/03/25 00:00 [accepted] PHST- 2004/10/02 05:00 [pubmed] PHST- 2005/01/28 09:00 [medline] PHST- 2004/10/02 05:00 [entrez] AID - S1570-0232(04)00632-4 [pii] AID - 10.1016/j.jchromb.2004.03.078 [doi] PST - ppublish SO - J Chromatogr B Analyt Technol Biomed Life Sci. 2004 Nov 5;811(1):93-101. doi: 10.1016/j.jchromb.2004.03.078.