Video Experimental Relacionado
Updated: Jul 9, 2026
07:30
In Vitro Model of Physiological and Pathological Blood Flow with Application to Investigations of Vascular Cell Remodeling
Published on: November 3, 2015
La acidificación citosólica dependiente del flujo de las células endoteliales vasculares
R C Ziegelstein1, L Cheng, M C Capogrossi
1Laboratory of Cardiovascular Science, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224.
Science (New York, N.Y.)
|October 23, 1992
Resumen
El estrés por cizallamiento laminar disminuye rápidamente el pH citosólico en las células endoteliales de la aorta de la rata. Esto ocurre a través de la activación de los intercambiadores de iones sodio-hidrógeno y cloruro-bicarbonato, afectando la función celular.
Área de la Ciencia:
- Fisiología Fisiología Fisiología.
- Biología celular Biología celular.
- La bioquímica es la bioquímica.
Sus antecedentes:
- El estrés de cizallamiento hemodinámico influye en la estructura y función de las células endoteliales.
- Los mecanismos de transducción de señales que subyacen a estos efectos no se comprenden completamente.
Objetivo del estudio:
- Para investigar el efecto de la tensión de cizallamiento laminar en el pH citosólico (pHi) en las células endoteliales de la aorta en ratas.
- Para dilucidar los mecanismos de intercambio iónico involucrados en los cambios de pHi inducidos por el estrés de cizallamiento.
Principales métodos:
- Celdas endoteliales aórticas cultivadas de rata en tubos capilares de vidrio.
- Tensión laminar aplicada y cambios medidos en el pH citosólico.
- Utilizó inhibidores de la eliminación de iones y el intercambio de iones para identificar vías de transporte de iones.
Principales resultados:
- La tensión de cizallamiento laminar causó una rápida disminución del pHi, con un efecto máximo de 0,09 unidades de pH a 13,4 dines/cm2.
- La tensión de corte activó el intercambio iónico cloruro-bicarbonato independiente del sodio (extrusora alcalina) y el intercambio iónico sodio-hidrógeno (extrusora ácida).
- El efecto neto en el amortiguador fisiológico con bicarbonato fue una disminución en el pHi.
Conclusiones:
- El estrés de corte hemodinámico modula el pHi de las células endoteliales a través de la activación coordinada de extrusores alcalinos y ácidos.
- Estos mecanismos de transporte de iones son críticos para regular la función de las células endoteliales bajo estrés de cizallamiento.
- La comprensión de estas vías proporciona una visión de la mecanotransducción en el endotelio vascular.
Videos de Conceptos Relacionados
01:20Overview of the Vascular System
The vascular system comprises an extensive network of arteries, capillaries, and veins. The vascular system can be broadly divided into the blood and lymphatic systems. Typically, blood vessels can be categorized into three histological regions: tunica intima, tunica media, and tunica adventitia. The tunica intima consists of a single layer of endothelial cells attached to the basal lamina. Underlying the basal lamina is a connective tissue layer and an elastic lamina that gives stability and...
01:24Regulation of Angiogenesis and Blood Supply
Rapidly dividing tumors, embryos, and wounded tissues require more oxygen than usual, lowering the oxygen concentration in the blood. At low oxygen or hypoxic conditions, an oxygen-sensitive transcription factor called the hypoxia-inducible factor 1 or HIF1 is activated. HIF1 is a dimeric protein of alpha (ɑ) and beta (β) subunits. Under optimal oxygen conditions, HIF1β is present in the nucleus while HIF1ɑ remains in the cytosol. HIF1ɑ is hydroxylated by prolyl hydroxylase and factor...
01:16Vascular Spasm
The vascular phase, also known as vasospasm, is the initial stage of hemostasis, crucial for preventing excessive bleeding when a blood vessel is injured. After a vessel is cut, nerves in the damaged area trigger pain and other sensory impulses. Simultaneously, the smooth muscles in the vessel wall contract, resulting in a vascular spasm. This contraction reduces the vessel's diameter at the injury site, slowing or stopping blood loss through the vessel wall. Vascular spasms typically last for...
01:15Structure of Blood Vessels
Blood is circulated throughout the human body through a network of blood vessels called the circulatory system. This system includes arteries that transport blood from the heart to various body parts. These arterial pathways divide into smaller vessels until they reach the arterioles, which further split into capillaries. It is within these minuscule capillaries that the exchange of nutrients and waste products takes place. After this exchange, the blood is collected by venules, which fuse to...
01:16Arteries and Arterioles
Arteries, the vasculature responsible for transporting blood from the heart, possess robust walls capable of enduring the elevated pressures exerted by the heartbeat. Arteries near the heart are especially thick-walled and enriched with elastic fibers across their three tunics, classifying them as elastic or conducting arteries. These arteries, usually with a diameter exceeding 10 mm, are characterized by their ability to dilate in response to the blood pumped from the heart's ventricles and...
01:17Autoregulation of Blood Flow
Autoregulation mechanisms are characterized by their inherent capacity for self-regulation without necessitating specific nervous stimulation or endocrine control. These mechanisms facilitate the adjustment of blood flow and, therefore, perfusion specific to each tissue region. This self-regulation encompasses chemical signals and myogenic controls.
Chemical Signaling in Autoregulation
Chemical signaling operates at the precapillary sphincter level, inciting either contraction or relaxation.
Chemical Signaling in Autoregulation
Chemical signaling operates at the precapillary sphincter level, inciting either contraction or relaxation.