Consequences of the evolutionary cardiovascular challenge of human bipedalism: orthostatic intolerance syndromes, orthostatic hypertension

In quadrupeds, the arterial baroreflex has dominance in the reflex homeostatic responses, which protect against haemorrhage. In humans, it is the low pressure cardiopulmonary reflex, which protects against the analogous cardiovascular challenge of gravity-dependent venous pooling with standing. To preserve orthostatic cardiovascular homeostasis with the emergence of bipedalism in humans the low pressure reflex, a minor, subsidiary reflex in quadripeds, was co-opted. Mirroring the imperfect skeletal evolution to bipedalism, this cardiovascular development has been problematic, with dysregulation manifesting as disabling orthostatic intolerance syndromes and, paradoxically, an orthostatic hypertensive response that appears to play a role in the development of essential hypertension in some people. Improved understanding of these evolutionary faults provides new options for postural and pharmacological treatments.
Source: Journal of Hypertension - Category: Cardiology Tags: REVIEWS AND META-ANALYSES Source Type: research

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Source: American Journal of Physiology. Heart and Circulatory Physiology - Category: Physiology Authors: Tags: Am J Physiol Heart Circ Physiol Source Type: research
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Source: Frontiers in Physiology - Category: Physiology Source Type: research
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Source: American Journal of Physiology. Regulatory, Integrative and Comparative Physiology - Category: Physiology Authors: Tags: Am J Physiol Regul Integr Comp Physiol Source Type: research
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Source: American Journal of Physiology. Regulatory, Integrative and Comparative Physiology - Category: Physiology Authors: Tags: Am J Physiol Regul Integr Comp Physiol Source Type: research
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Source: Journal of Spinal Cord Medicine - Category: Orthopaedics Tags: J Spinal Cord Med Source Type: research
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Source: Journal of Molecular and Cellular Cardiology - Category: Cytology Authors: Source Type: research
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Source: Pharmacological Research - Category: Drugs & Pharmacology Source Type: research
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Source: The Journal of Physiology - Category: Physiology Authors: Tags: J Physiol Source Type: research
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