title: Impairment of modulating role of testosterone in growth hormone response to clonidine in essential hypertension.
abstract: 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.
authors.affiliation: Second Department of Internal Medicine, School of Medicine, Kanazawa University, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Koshida
authors.forename: I
authors.initials: I
authors.lastname: Miyamori
authors.forename: H
authors.initials: H
authors.lastname: Takasaki
authors.forename: R
authors.initials: R
authors.lastname: Takeda
mesh_terms: 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*
chemical_list: D013739:Testosterone; D013006:Growth Hormone; D003000:Clonidine