Adiposity is related to gender differences in impaired stress-induced pressure natriuresis.
The purpose of this study was to determine if there are gender differences in stress-induced pressure natriuresis and to examine the effects of adiposity on these differences. The subjects were 151 boys and 141 girls 15 to 18 years of age who underwent a 5-hour stress protocol (2-hour prestress, 1-hour stress, 2-hour poststress) after being brought into similar levels of sodium balance. The gender-by-condition interaction was significant for systolic and diastolic blood pressure (P=0.001 for both), and the effect of condition was significant for sodium excretion (P=0.001). Systolic blood pressure was higher for boys throughout the protocol (P=0.001 for each) and correlated with body mass index at each condition (range in r=0.28 to 0.35; P<0.001 for each). Hemodynamically, in boys body mass index was correlated with cardiac output during stress (r=0.23; P=0.006), which was correlated with systolic blood pressure (r=0.21; P=0.01). With respect to natriuresis, body mass index was inversely correlated with sodium excretion during stress (r=-0.22; P=0.008) and positively correlated with angiotensin II in a subsample of boys (n=89: r=0.31; P=0.003). The inverse correlation between angiotensin II and sodium excretion during stress approached significance (r=-0.17; P<0.06). Similar results were not observed for girls. In conclusion, gender differences in stress-induced pressure natriuresis appear to be related to the influence of adiposity on both blood pressure and natriuresis.
Harshfield
Gregory A
GA
Georgia Prevention Institute, Medical College of Georgia, MCG Annex H.S. 1640, Augusta, Ga 30912-4534, USA. Gharshfi@mail.mcg.edu
Wilson
Martha E
ME
McLeod
Kathryn
K
Hanevold
Coral
C
Kapuku
Gaston K
GK
Mackey
Lynne
L
Gillis
Delores
D
Edmonds
Lesley
L
D000273:Adipose Tissue / Q000473:pathology; D000293:Adolescent; D000809:Angiotensins / Q000502:physiology; D001794:Blood Pressure; D015992:Body Mass Index; D005260:Female; D006439:Hemodynamics; D006801:Humans; D007328:Insulin / Q000502:physiology; D008297:Male; D009318:Natriuresis; D012737:Sex Factors; D012964:Sodium / Q000652:urine; D013312:Stress, Physiological / Q000473:pathology / Q000503:physiopathology / Q000652:urine
D000809:Angiotensins; D007328:Insulin; D012964:Sodium