Growth hormone response in low-dose apomorphine test correlates with nigrostriatal dopamine transporter binding in patients with Parkinson's disease.
Challenge with low-dose apomorphine causes a rise in growth hormone (GH) in patients with Parkinson's disease (PD). We studied 18 patients with early PD, who showed an increase of GH in the low-dose apomorphine test, by means of [(123)I] FP-CIT-SPECT. The mean specific dopamine transporter binding of the 18 patients was 1.50 +/- 0.56 in the striatum, 1.20 +/- 0.59 in the putamen, and 1.76 +/- 0.59 in the caudate nucleus. The increase of GH (1.05 +/- 1.01 ng/ml at baseline to 9.46 +/- 6.36 ng/ml 45 min after apomorphine injection; p < 0.001) was significant. There was a significant negative correlation of the increase of GH with the mean specific dopamine transporter binding in all three regions (r between -0.490 and -0.587; p between 0.04 and 0.01). Challenge with low-dose apomorphine may therefore be used as an indirect tool to measure the extent of nigrostriatal neurodegeneration in early PD.
Happe
S
S
Department of Clinical Neurophysiology, University of Göttingen, Göttingen, Germany. Svenja.Happe@klinikum-bremen-ost.de
Tings
T
T
Koch
W
W
Welsch
J
J
Helmschmied
K
K
Baier
P C
PC
Meller
J
J
Wuttke
W
W
Paulus
W
W
Tatsch
K
K
Trenkwalder
C
C
D000328:Adult; D000368:Aged; D001058:Apomorphine / Q000494:pharmacology; D001667:Binding, Competitive / Q000187:drug effects / Q000502:physiology; D003342:Corpus Striatum / Q000000981:diagnostic imaging / Q000378:metabolism* / Q000503:physiopathology; D004298:Dopamine / Q000378:metabolism; D018491:Dopamine Agonists / Q000494:pharmacology; D050483:Dopamine Plasma Membrane Transport Proteins / Q000378:metabolism*; D005260:Female; D013006:Growth Hormone / Q000032:analysis / Q000097:blood*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010300:Parkinson Disease / Q000000981:diagnostic imaging* / Q000378:metabolism* / Q000503:physiopathology; D011237:Predictive Value of Tests; D013378:Substantia Nigra / Q000000981:diagnostic imaging / Q000378:metabolism* / Q000503:physiopathology; D015899:Tomography, Emission-Computed, Single-Photon; D014326:Tropanes / Q000493:pharmacokinetics
D018491:Dopamine Agonists; D050483:Dopamine Plasma Membrane Transport Proteins; D014326:Tropanes; C087552:2-carbomethoxy-8-(3-fluoropropyl)-3-(4-iodophenyl)tropane; D013006:Growth Hormone; D001058:Apomorphine; D004298:Dopamine