The goals of this research are to more fully understand the basis for individual differences in cardiovascular reactivity to stress and to assess whether particularly hyperreactive individuals are at increased risk for the development of hypertension. The proposed strategy is to conduct initial laboratory studies to provide a detailed evaluation of behavioral and physiological characteristics of a group of young men (aged 18-25) with normal or elevated casual blood pressure. A follow-up study will then assess long-term aspects of blood pressure regulation and attempt to relate these to initial test characteristics. Initial testing will involve exposure to standard laboratory stressors such as a reaction-time shock-avoidance task, mental arithmetic and cold pressor. The opportunity for greater behavioral flexibility will also be introduced by presenting choice of task difficulty, as well as including a speech evaluation stressor, with the aim of assessing whether this may reveal a closer link between reactivity and personality traits (e.g., Type Alpha). Non-invasive measurements will include blood pressure and cardiac output, permitting the derivation of systemic vascular resistance responses and the hemodynamic basis of pressor reactivity. Invasive procedures include venous blood sampling for plasma catecholamines and pharmacological manipulations designed to permit the evaluation of cardiovascular alpha- and beta- adrenergic receptor sensitivities. The data collected from these studies will be analyzed with the general aim of assessing the relative contributions of behavioral characteristics, sympathetic nervous system activation and target adrenoceptor sensitivities in determining individual differences in cardiovascular reactivity to stress. At follow-up, 2-3 years later, catecholamine responses and adrenergic receptor sensitivities will be re-evaluated in relation to the long term stability of stress reactivity and changes in resting blood pressure. Together, these studies are aimed at understanding the mechanisms by which behavior may play a role in the etiology of hypertension.

Agency
National Institute of Health (NIH)
Institute
National Heart, Lung, and Blood Institute (NHLBI)
Type
First Independent Research Support & Transition (FIRST) Awards (R29)
Project #
5R29HL038950-03
Application #
3471454
Study Section
Behavioral Medicine Study Section (BEM)
Project Start
1988-12-01
Project End
1993-11-30
Budget Start
1990-12-15
Budget End
1991-11-30
Support Year
3
Fiscal Year
1991
Total Cost
Indirect Cost
Name
University of North Carolina Chapel Hill
Department
Type
Schools of Medicine
DUNS #
078861598
City
Chapel Hill
State
NC
Country
United States
Zip Code
27599
Suarez, E C; Sherwood, A; Hinderliter, A L (1998) Hostility and adrenergic receptor responsiveness: evidence of reduced beta-receptor responsiveness in high hostile men. J Psychosom Res 44:261-7
Sherwood, A; Hinderliter, A L; Light, K C (1995) Physiological determinants of hyperreactivity to stress in borderline hypertension. Hypertension 25:384-90
Sherwood, A; May, C W; Siegel, W C et al. (1995) Ethnic differences in hemodynamic responses to stress in hypertensive men and women. Am J Hypertens 8:552-7
Sherwood, A; Royal, S A; Light, K C (1993) Laboratory reactivity assessment: effects of casual blood pressure status and choice of task difficulty. Int J Psychophysiol 14:81-95
Sherwood, A; Hinderliter, A L (1993) Responsiveness to alpha- and beta-adrenergic receptor agonists. Effects of race in borderline hypertensive compared to normotensive men. Am J Hypertens 6:630-5
Sherwood, A; Royal, S A; Hutcheson, J S et al. (1992) Comparison of impedance cardiographic measurements using band and spot electrodes. Psychophysiology 29:734-41
Light, K C; Dolan, C A; Davis, M R et al. (1992) Cardiovascular responses to an active coping challenge as predictors of blood pressure patterns 10 to 15 years later. Psychosom Med 54:217-30
Sherwood, A; Davis, M R; Dolan, C A et al. (1992) Cardiovascular reactivity assessment: effects of choice of difficulty on laboratory task responses. Int J Psychophysiol 12:87-94
Turner, J R; Sherwood, A (1991) Postural effects on blood pressure reactivity: implications for studies of laboratory-field generalization. J Psychosom Res 35:289-95