Sodium-induced rise in blood pressure is suppressed by androgen receptor blockade.
Our objective was to test the hypothesis that 1) a high Na (HNa, 3%) diet would increase blood pressure (BP) in male Wistar-Kyoto (WKY) and spontaneously hypertensive Y chromosome (SHR/y) rat strains in a territorial colony; 2) sympathetic nervous system (SNS) blockade using clonidine would lower BP on a HNa diet; and 3) prepubertal androgen receptor blockade with flutamide would lower BP on a HNa diet. A 2 x 4 factorial design used rat strains (WKY, SHR/y) and treatment [0.3% normal Na (NNa), 3% HNa, HNa/clonidine, and HNa/flutamide]. BP increased in both strains on the HNa diet (P < 0.0001). There was no significant decrease in BP in either strain with clonidine treatment. Androgen receptor blockade with flutamide significantly decreased BP in both strains (P < 0.0001) and normalized BP in the SHR/y colony. Neither heart rate nor activity could explain these BP differences. In conclusion, a Na sensitivity was observed in both strains, which was reduced to normotensive values by androgen blockade but not by SNS blockade.
Caplea
A
A
Department of Biology, The University of Akron, Akron, Ohio 44325-3908, USA. Ely1@uakron.edu
Seachrist
D
D
Dunphy
G
G
Ely
D
D
D000704:Analysis of Variance; D000726:Androgen Antagonists / Q000494:pharmacology*; D059002:Androgen Receptor Antagonists; D000818:Animals; D001794:Blood Pressure / Q000187:drug effects* / Q000502:physiology; D003000:Clonidine / Q000494:pharmacology; D003433:Crosses, Genetic; D005260:Female; D005485:Flutamide / Q000494:pharmacology*; D006973:Hypertension / Q000235:genetics / Q000503:physiopathology* / Q000517:prevention & control; D008297:Male; D051381:Rats; D011918:Rats, Inbred SHR; D011921:Rats, Inbred WKY; D012741:Sexual Maturation; D012982:Sodium, Dietary / Q000494:pharmacology*; D013045:Species Specificity; D013599:Systole; D013731:Territoriality; D014998:Y Chromosome
D000726:Androgen Antagonists; D059002:Androgen Receptor Antagonists; D012982:Sodium, Dietary; D005485:Flutamide; D003000:Clonidine