Sex differences in integrated neuro-cardiovascular control of blood pressure following acute intermittent hypercapnic-hypoxia.

Sex differences in integrated neuro-cardiovascular control of blood pressure following acute intermittent hypercapnic-hypoxia. Am J Physiol Regul Integr Comp Physiol. 2020 Sep 23;: Authors: Jacob DW, Ott EP, Baker SE, Scruggs ZM, Ivie CL, Harper JL, Manrique-Acevedo CM, Limberg JK Abstract Repetitive hypoxic apneas, similar to that observed in sleep apnea, result in resetting of the sympathetic baroreflex to higher blood pressures (BP). This baroreflex resetting is associated with hypertension in preclinical models of sleep apnea (intermittent hypoxia, IH); however, the majority of understanding comes from males. There are data to suggest female rats exposed to IH do not develop high BP. Clinical data further support sex differences in the development of hypertension in sleep apnea, but mechanistic data are lacking. Herein we examined sex-related differences in the effect of IH on sympathetic control of BP in humans. We hypothesized following acute IH, we would observe a rise in muscle sympathetic nerve activity (MSNA) and arterial BP in young men (n=30) which would be absent in young women (n=19). BP and MSNA were measured during normoxic rest prior to and following 30-minutes of IH. Baroreflex sensitivity (modified Oxford) was evaluated before and after IH. A rise in mean BP following IH was observed in men (+2.0±0.7 mmHg, p=0.03), whereas no change was observed in women (-2.7±1.2 mmHg, p=0.11). The elevation in MSNA following IH...
Source: American Journal of Physiology. Regulatory, Integrative and Comparative Physiology - Category: Physiology Authors: Tags: Am J Physiol Regul Integr Comp Physiol Source Type: research