Objective To determine whether peripheral hemodynamic differences exist in young adult normotensive African Americans and white Americans with a positive and negative parental history of hypertension.
Methods The participants were healthy men of whom 13 were African Americans and nine white Americans with a positive parental history and 19 were African Americans and 13 white Americans with a negative parental history. Lower leg blood flows were obtained at rest and during reactive hyperemia. Lower leg minimum vascular resistance (Rmin) was computed from reactive hyperemic blood flow measured by venous occlusion plethysmography, and mean arterial blood pressure was determined by auscultation of the brachial artery.
Results Resting blood flow and mean arterial pressure were similar in all groups. A significant racex parental history interaction effect was observed for lower leg Rmin. In the white men the lower leg Rmin was significantly greater in the positive than the negative parental group (P < 0.05). Lower leg Rmin was significantly greater in African Americans than in white men without a parental history (P < 0.05). Mean arterial blood pressure and heart rate were similar among the groups.
Conclusions This study demonstrates that lower leg Rmin is greater in young white men with a positive parental history of hypertension than those with a negative parental history. In African Americans with either positive or negative parental histories, lower leg Rmin is not different. This finding suggests that heredity may have a greater influence in white populations than in African Americans on the structural changes in resistance vessels. The study also suggests that African Americans have an earlier structural change in the resistance vessels compared with white people, regardless of a parental history of hypertension. This suggests that factors other than heredity are of importance in changing the structure of the resistance vessels.
AdamsJM: Some racial differences in blood pressure and morbidity in groups of white and colored workmenAm J Med Sci1932, 184:342.
2.
National Health Survey: Blood pressure of persons 18–74 years in the United States 1971–1972Vital Health Stat1975, 2:150.
3.
StamlerRStamlerJRiedlingerWAlgeraGRobertsRH: Family (parental) history and prevalence of hypertension: Results of a nationwide screening programJAMA1979, 241:43–47.
4.
CarberryPAShepherdAMMJohnsonJM: Resting and maximal forearm skin blood flows are reduced in hypertensionHypertension1992, 20:349–355.
5.
TakeshitaAImaizumiTAshiharaTYamamotoKHokaSNakamuraM: Limited maximal vasodilatory capacity of forearm resistance vessels in normotensive young men with a familial predisposition to hypertensionCirc Res1982, 50:671–677.
6.
BorghiCVCostaFVBoschiSEttoreA: Impaired vasodilatory capacity and exaggerated pressor response to isometric exercise in subjects with family history of hypertensionAm J Hypertens1988, 1:106S–109S.
7.
BondVFranksBDTearneyRJWoodBMelendezMAJohnsonL: Exercise blood pressure response and skeletal muscle vasodilator capacity in normotensives with positive and negative family history of hypertensionJ Hypertens1994, 12:285–290.
8.
BassettDRJrDueyWJWalkerAJHowleyETBondV: Racial differences in maximal vasodilatory capacity of forearm resistance vessels in normotensive young adultsAm J Hypertens1992, 5:781–786.
9.
GrangerHJGoodmanAHCookBH: Metabolic models of microcirculatory regulationFed Proc1975, 34:2025–2030.
10.
RomanovskaLPrerovskyIStribrnaJ: Blood flow and vascular resistance in lower limbs in hypertensives at rest and at reactive hyperaemiaCor Vasa1977, 19:61–65.
11.
FolkowBGrimbyGThulesiusO: Adaptive structural changes of the vascular walls in hypertension and their relation to the control of peripheral resistanceActa Physiol Scand1958, 44:255–272.
12.
FolkowB: Physiological aspects of primary hypertensionPhysiol Rev1982, 62:347–504.
13.
SivertssonR: Structural adaptation in borderline hypertensionHypertension1984, 6 (suppl III):III103–III107.
14.
Lund-JohansenI: Central hemodynamics in essential hypertension at rest and during exercise – a 20 year follow-up studyJ Hypertens1989, 7:S52–S55.
15.
HarshfieldGAHwangCGrimCE: Circadian variation of blood pressure in blacks: Influence of age, gender and activityJ Hum Hypertens1990, 4:43–47.
16.
HarshfieldGAPickeringTGKleinertHDBlankSLaraghJH: Situational variations of blood pressure in ambulatory hypertensive patientsPsychosom Med1982, 44:237–245.
17.
HenrichHARomenWHeimgartnerWHariungEBaumerF: Capillary rarefaction characteristics of the skeletal muscle of hypertensive patientsKlin Wochenschr1988, 66:54–60.
18.
Ben Bachir-LamriniLSemporeBMayetM-HFavierRS: Evidence of a slow-to-fast fiber type transition in skeletal muscle from spontaneously hypertensive ratsAm J Physiol1990, 258:R352–R357.
19.
AmaPFMSimoneauJABoulayMRSerresseOTheriaultGBouchardC: Skeletal muscle characteristics in sedentary black and Caucasian malesJ Appl Physiol1986, 61:1758–1761.
20.
SaltinBGollnickPD: Skeletal muscle adaptability significance for metabolism and performance In Handbook of Physiology, Section 10: Skeletal Muscle. Edited by PeachyLDAdrianRHGeigerSR.Baltimore: Williams and Wilkins; 1983:555–631.
