Insulin sensitivity, sympathetic activity, and cardiovascular reactivity in young men

Abstract

The present study was undertaken to examine the relationships between insulin sensitivity, blood pressure (BP), and cardiovascular reactivity, and to assess sympathetic nervous system influence. Insulin sensitivity (GDR/I; euglycemic glucose clamp technique) was related to BP and heart rate (HR) in different situations in 40 healthy young men: in the laboratory, during a mental arithmetic stress test, and during baseline conditions at home. GDR/I correlated with supine diastolic BP in the laboratory and with maximum diastolic BP during mental stress (r = -0.46, P = .003; r = -0.62, P = .0001, respectively), but not so strongly with diastolic BP measured at home (r = -0.29, P = .09). Diastolic BP during stress and body mass index were the only independent explanatory variables of GDR/I in multiple regression analysis (multiple R = 0.71, R2 = 0.50, P < .0001). GDR/I and systolic BP were not significantly correlated at any time. GDR/I correlated negatively with HR in the laboratory and with maximum HR during mental stress, but not with HR at home. Maximum plasma epinephrine during stress correlated with stress BP and HR (r = 0.53, P = .001; r = 0.70, P < .0001, respectively) and negatively with GDR/I (r = -0.36, P < .05). In the present study, GDR/I is related to diastolic but not to systolic BP, and more closely correlated to diastolic BP and HR measured during mental stress than to diastolic BP and HR during baseline conditions at home.(ABSTRACT TRUNCATED AT 250 WORDS)

Insulin Sensitivity Is Related to Physical Fitness and Exercise Blood Pressure to Structural Vascular Properties in Young Men

“…These 3 measurements could be considered as different stress situations and show results similar to those previously shown with a mental stress test. 8,11 In accordance, daytime BP did not differ significantly between the groups.…”

“…As reported previously, 11 men recruited this way are normotensive as documented through normal home BP readings. However, they are hyperreactive to mental stress 11 ; BP values recorded during the draft procedure could be considered as office BP or BP during an alert reaction. In the present study, the men in the tertile with the highest exercise SBP also had significantly higher office and preexercise BP values than the men in the lowest tertile.…”

“…In support of this hypothesis, we have previously shown a positive correlation between insulin resistance and determinants of peripheral blood flow, such as calculated 4 and directly measured 3 WBV and structural vascular changes as assessed by MFVR. 8 Furthermore, in these young men, insulin resistance is closely and positively related to sympathetic activity and BP responses during mental stress, 8,11 and BP responses during mental stress correlate closely and positively with MFVR. 8 Systolic BP (SBP), taken after 6 minutes on the first load of 600 kilo/pound/meter [kpm] per min (Ϸ100 W) during an ergometer bicycle exercise test in middle-aged healthy Norwegian men, 9 was a strong independent risk factor for cardiovascular death 12 and death from myocardial infarction.…”

Physical activity, adiposity and hypertension among patients of public healthcare system

“…However, abdominal obesity has been pointed out as being more harmful to health then overall obesity. The mechanisms through which abdominal fat is associated with increasing blood pressure values may be due to hyperinsulinemia, which causes more activity in the sympathetic nervous system and tubular sodium reabsorption [38][39][40] ; such actions contribute with high blood pressure values. On the other hand, insulin is related to the promotion of vasodilation, and leads to increasing blood flow to the skeletal musculature, and such an effect seems to be mediated by nitric oxide 41,42 .…”

Effects of Sibutramine on the Treatment of Obesity in Patients with Arterial Hypertension

“…Several hypotheses exist for the pathophysiology of arterial hypertension in this obese population. The first and more accepted hypothesis proposes that hyperinsulinemia secondary to insulin resistance existing in these patients leads to greater sympathetic activity and to renal sodium retention, which would account for the increase in pressure levels [6][7][8] . The second hypothesis associates the arterial hypertension existing in these patients with the mechanical compression of renal parenchyma by visceral fat.…”