Chronic intermittent hypoxia (CIH) induces sympathetic overactivity and hypertension in male rats. Enhanced respiratory modulation of sympathetic activity in juvenile male rats exposed to CIH occurs in the expiratory phase of the respiratory cycle, characterizing changes in respiratory-sympathetic coupling. Different from other experimental models of hypertension, CIH induces increase in arterial pressure in adult female rats similarly to that observed in male rats. However, the mechanisms underlying the hypertensive phenotype in CIH-female rats remain to be elucidated. Moreover, several evidences documented sex differences in the respiratory network activity in response to hypoxia. Considering that CIH-male rats present an increase in the respiratory modulation of sympathetic activity and there are sex differences in the respiratory network, we hypothesized that CIH-female rats develop an increase in the respiratory modulation of sympathetic activity different from CIH-male rats. In this study we investigated sympathetic and respiratory activities in juvenile female rats exposed to CIH using an in situ working heart-brainstem preparation. CIH-female rats develop changes in the respiratory pattern and changes in the respiratory-sympathetic coupling marked by sympathetic overactivity phase-locked to inspiration, which is different in relation to male rats exposed to CIH. This study revealed a specific respiratory-related mechanism for sympathetic overactivity linked to inspiration that explains, at least in part, the hypertensive phenotype in female rats exposed to CIH.
This article is protected by copyright. All rights reserved
from Physiology via xlomafota13 on Inoreader http://ift.tt/2c3EgNR
via IFTTT
Δεν υπάρχουν σχόλια:
Δημοσίευση σχολίου
Σημείωση: Μόνο ένα μέλος αυτού του ιστολογίου μπορεί να αναρτήσει σχόλιο.