The impact of menstrual phase on brachial artery flow‐mediated dilatation during handgrip exercise in healthy premenopausal women

• DOI: 10.1113/ep086311
• Publication Date: 2017-10-30T11:02:58Z
• Authors: Katrina A. D'Urzo; Trevor J. King; Jennifer S. Williams; Morgan D. Silvester; Kyra E. Pyke
• Keywords: Brachial artery

What is the central question of this study? The aim study was to determine influence menstrual phase on flow-mediated dilatation in response sustained, exercise-induced increases shear stress. main finding and its importance? We showed, for first time, that healthy, premenopausal women stimulated by stress did not fluctuate across two phases cycle, despite significant fluctuations oestrogen. This suggests endothelial function consistently augmented high-oestrogen phase. Flow-mediated (FMD) a sustained shear-stress stimulus (e.g. via handgrip exercise; HGEX) emerging as useful tool assessing function; however, impact HGEX-FMD unknown. purpose whether fluctuates with cyclical changes oestrogen concentrations over discrete (low high oestrogen) cycle. Brachial artery (BA) diameter blood velocity were assessed two-dimesional Doppler ultrasound, respectively. Shear estimated using rate (SR = BA velocity/BA diameter). Participants (12 regularly cycling women, 21 ± 2 years age) completed experimental visits: (i) low (early follicular, EF); (ii) (late LF). Reactive hyperaemia-stimulated FMD (RH-FMD) (6 min exercise) during each visit. Results are mean values SD. Oestrogen increased from EF LF (EF, 33 9 pg ml-1 ; LF, 161 113 , P 0.003). However, neither SR stimuli (HGEX, 0.501; RH, 0.173) nor responses differed between (EF versus LF: HGEX-FMD, 4.8 2.8 4.6 2.2%, 0.601; RH-FMD, 7.9 4.3 6.4 3.1%, 0.071). These results extend existing RH-FMD findings indicating all experience Further research needed investigate mechanisms underlie variability FMD.