title: Smoking, dopamine transporter, and hand tremor.
abstract: OBJECTIVE
  The purpose of the study was to evaluate the relationship between the number of packs smoked per day and specific uptake ratio (SUR) in the striatum on Tc-99m TRODAT, and frequency of hand tremor.
  
  
  METHODS
  It was a prospective, cross-sectional study. In all, 23 healthy nonsmokers and 37 current smokers were recruited in the study. All subjects underwent Tc-99m TRODAT SPECT, brain CT scan, thyroid function test, tremor measurement system, and neurologic examinations.
  
  
  RESULTS
  There were significant differences in the SUR in the striatum on Tc-99m TRODAT and in the frequency of hand tremor in rest state and in arm extended state among nonsmokers (grade I), current smokers with less than 1 pack smoked per day (grade II), and current smokers with equal or more than 1 pack smoked per day (grade III) by ANOVA (all P < 0.001). After adjusting for age and gender, there was a significantly negative correlation between smoke grade and SUR in the striatum on Tc-99m TRODAT by multiple linear regression (β = -0.45, P < 0.001). Smoke grade was the significant predictor for the frequency of hand tremor in rest state and in arm extended state, after adjusting for age and gender by multiple linear regression (β = 14.70, P < 0.001; β = 15.37, P < 0.001).
  
  
  CONCLUSIONS
  There is a dose-response relationship between the number of packs smoked per day and SUR in the striatum, and the frequency of hand tremor. Decreased dopamine transporter binding in the striatum and increased frequency of hand tremor in smokers may have important implications for evaluating the impact of smoking on the central and peripheral nerve systems.
authors.affiliation: Graduate School of Biotechnology, Hungkuang University, Taichung, Taiwan.
authors.forename: Chun-Yi
authors.initials: CY
authors.lastname: Lin
authors.forename: Chung-Hsin
authors.initials: CH
authors.lastname: Yeh
authors.forename: Tien-Tien
authors.initials: TT
authors.lastname: Chang
authors.forename: Chia-Hong
authors.initials: CH
authors.lastname: Kao
authors.forename: Song-Yen
authors.initials: SY
authors.lastname: Tsai
mesh_terms: D000328:Adult; D001921:Brain / Q000000981:diagnostic imaging / Q000378:metabolism*; D050483:Dopamine Plasma Membrane Transport Proteins / Q000378:metabolism*; D005260:Female; D006225:Hand / Q000000981:diagnostic imaging; D006801:Humans; D008297:Male; D015609:Organotechnetium Compounds / Q000493:pharmacokinetics*; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals / Q000493:pharmacokinetics; D012907:Smoking / Q000378:metabolism*; D014202:Tremor / Q000000981:diagnostic imaging / Q000378:metabolism*; D014326:Tropanes / Q000493:pharmacokinetics*
chemical_list: D050483:Dopamine Plasma Membrane Transport Proteins; D015609:Organotechnetium Compounds; D019275:Radiopharmaceuticals; D014326:Tropanes; C104196:technetium Tc 99m TRODAT-1