Stereospecificity of the dopamine receptor mediating the growth hormone response to apomorphine in man. Short communication.
The stereospecificity of the D-2 receptor mediating the growth hormone (GH) response to apomorphine (Apo) and the D-2 receptor regulating prolactin (PRL) secretion were investigated in 10 normal men by examining the effects of cis-flupenthixol (cis-Fx) and trans-flupenthixol (trans-Fx). cis-Fx (1 mg six hourly times four doses) antagonized the GH response to Apo HCl (0.5 mg sc) and increased basal serum PRL concentrations whereas the trans-isomer showed no effect. These findings (a) provide further evidence that the GH response to Apo is mediated by stimulating dopamine (DA) receptors, and, (b) demonstrate stereospecificity of the DA receptor mediating the GH response to Apo and the DA receptor regulating PRL secretion.
Douglas Hospital Research Center, Verdun, Montreal, Canada.
S
S
Lal
N P
NP
Nair
J X
JX
Thavundayil
V
V
Tawar
R
R
Quirion
H
H
Guyda
D000328:Adult; D001058:Apomorphine / Q000494:pharmacology*; D005475:Flupenthixol / Q000494:pharmacology*; D013006:Growth Hormone / Q000097:blood*; D006801:Humans; D008297:Male; D011388:Prolactin / Q000097:blood*; D011954:Receptors, Dopamine / Q000187:drug effects*; D013237:Stereoisomerism
D011954:Receptors, Dopamine; D011388:Prolactin; D013006:Growth Hormone; D005475:Flupenthixol; D001058:Apomorphine