title: Abnormal neurovascular control during sympathoexcitation in obesity.
abstract: OBJECTIVE
  We tested the hypothesis that muscle sympathetic nerve activity (MSNA) and forearm vascular resistance (FVR) would be augmented during mental stress or cold pressor test in healthy obese individuals compared with healthy lean individuals.
  
  
  METHODS
  Twenty-nine healthy obese women and 12 age-matched healthy lean women were involved in the study. MSNA was directly measured from the peroneal nerve using microneurography. Forearm blood flow was measured by venous occlusion plethysmography. Blood pressure (BP) was monitored noninvasively by an automatic BP cuff, and heart rate (HR) was measured by electrocardiogram. Stroop color word test was performed for 4 minutes, and the cold pressor test was performed for 2 minutes.
  
  
  RESULTS
  Baseline MSNA and FVR were greater in the obese group than in the lean group. BP and HR were similar between groups. During mental stress, MSNA and FVR were greater in obese individuals than in lean individuals, although the magnitude of response was similar between groups. BP and HR similarly increased in obese and lean individuals. During the cold pressor test, MSNA, FVR, and BP were greater in obese individuals, but the magnitude of response was similar between groups. HR increased similarly during the cold pressor test in both obese and lean individuals.
  
  
  CONCLUSIONS
  Obesity increases MSNA and FVR during mental stress and the cold pressor test. This inappropriate neurovascular control can be expected to have an adverse effect on the risk factors for cardiovascular events and, hence, should be considered in the treatment of obese patients.
authors: Heart Institute (InCor), Medical School, University of São Paulo, São Paulo CEP 05403-000, Brazil.
authors: Fátima H S
authors: FH
authors: Kuniyoshi
authors: Ivani C
authors: IC
authors: Trombetta
authors: Luciana T
authors: LT
authors: Batalha
authors: Maria U P B
authors: MU
authors: Rondon
authors: Mateus C
authors: MC
authors: Laterza
authors: Márcia M G
authors: MM
authors: Gowdak
authors: Antonio C P
authors: AC
authors: Barretto
authors: Alfredo
authors: A
authors: Halpern
authors: Sandra M F
authors: SM
authors: Villares
authors: Eliudem G
authors: EG
authors: Lima
authors: Carlos E
authors: CE
authors: Negrão
mesh_terms: D000328:Adult; D001794:Blood Pressure; D003080:Cold Temperature; D005260:Female; D005542:Forearm / Q000098:blood supply; D006339:Heart Rate; D006801:Humans; D007101:Immersion; D009132:Muscles / Q000294:innervation*; D009765:Obesity / Q000503:physiopathology*; D010543:Peroneal Nerve / Q000503:physiopathology; D010991:Plethysmography; D013315:Stress, Psychological; D013564:Sympathetic Nervous System / Q000503:physiopathology*; D014655:Vascular Resistance