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Updated: Jul 18, 2026

Fixed Volume or Fixed Pressure: A Murine Model of Hemorrhagic Shock
Published on: June 6, 2011
Disturbances in hormonal regulation of vascular tone during traumatic shock
L M Kozhevnikova1, P V Avdonin
1Institute of General Pathology and Pathophysiology, Russian Academy of Medical Sciences, Moscow.
Abstract:
Changes in hormonal regulation of the vascular tone in Wistar rats were studied on Cannon model of traumatic shock. The pressor response to angiotensin II decreased by 30-40% 3 h after the incidence of trauma. The reaction to vasopressin remained unchanged. However, phenylephrine in medium and high doses produced a more pronounced pressor response under these conditions. One day after trauma we revealed a decrease in vascular sensitivity not only to angiotensin II, but also to vasopressin and alpha1-adrenoceptor agonist phenylephrine. The vascular response was observed only after treatment with phenylephrine in maximum doses. Traumatic shock was accompanied by inverse response to serotonin: hypertensive effect instead of blood pressure drop. Our results show that traumatic shock is accompanied by specific changes in vascular reactivity.
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