Impairment of modulating role of testosterone in growth hormone response to clonidine in essential hypertension.
To investigate the effects of endogenous testosterone (T) on the responsiveness of plasma growth hormone (GH) to central alpha 2 adrenergic stimulation, we administered clonidine (0.15 mg, p.o.) to 16 male patients with essential hypertension (EHT) and 13 age-matched male normotensive controls (NT). Although the basal T level was correlated with the peak GH increment (r = 0.709, p less than 0.01) and with the area under curve of GH (r = 0.714, p less than 0.01) in the NT group, no such correlations were seen in the EHT group. The present study confirmed the potentiating role of endogenous T in GH responsiveness to clonidine in male NT. The lack of correlation between T and GH response in EHT suggests a neuroendocrine disturbance in modulation by T of the GH response to central alpha 2 adrenergic stimulation.
Koshida
H
H
Second Department of Internal Medicine, School of Medicine, Kanazawa University, Japan.
Miyamori
I
I
Takasaki
H
H
Takeda
R
R
D000328:Adult; D001794:Blood Pressure / Q000187:drug effects; D003000:Clonidine / Q000494:pharmacology*; D013006:Growth Hormone / Q000097:blood*; D006801:Humans; D006973:Hypertension / Q000378:metabolism* / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D009994:Osmolar Concentration; D012016:Reference Values; D013739:Testosterone / Q000097:blood / Q000502:physiology*
D013739:Testosterone; D013006:Growth Hormone; D003000:Clonidine