Abstract
Purpose
We investigated the effects of group III mechanoreceptors to cardiovascular responses in both pre-menopausal woman and post-menopausal woman during passive ankle dorsiflexion (PAD).
Methods
Twenty healthy volunteers (10 post-menopausal women and 10 pre-menopausal women) were recruited for this study. Stroke volume (SV), heart rate (HR), cardiac output (CO), and total vascular conductances (TVC) were measured continuously throughout the experiment. To stimulate the group III mechanoreceptors, PAD was performed for one minute.
Results
The results showed that mean arterial pressure (MAP) mediated by the mechanoreflex activation was significantly increased in both groups. However, this pressor response was significantly higher in post-menopausal women. This reflex significantly increased both SV and CO in pre-menopausal women, while there were no differences in post-menopausal women. There was no difference in HR in either group. The mechanoreflex significantly decreased TVC in post-menopausal woman, while there was no difference in pre-menopausal woman.
Figures and Tables
Figure 2
Cardiovascular responses mediated by the mechanorefelx during foot ankle dorsiflexion.
Values are mean±standard error. PMW=Premenopausal woman; PTW=Postmenopausal woman; Black Bar: baseline; Gray Bar: mechanoreflex activation. *Significantly different from baseline value, p<.05; #Significantly different from PMW, p<.05; MAP=mean arterial pressure; HR=heart rate; SV=stroke volume; CO cardiac output; TVC=total vascular conductances.
![jkan-41-191-g002](/upload/SynapseData/ArticleImage/0006jkan/jkan-41-191-g002.jpg)
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