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.
Georgia Prevention Institute, Medical College of Georgia, MCG Annex H.S. 1640, Augusta, Ga 30912-4534, USA. Gharshfi@mail.mcg.edu
Gregory A
GA
Harshfield
Martha E
ME
Wilson
Kathryn
K
McLeod
Coral
C
Hanevold
Gaston K
GK
Kapuku
Lynne
L
Mackey
Delores
D
Gillis
Lesley
L
Edmonds
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