Related Experiment Video
Updated: Jun 18, 2026

Retinal Vascular Reactivity as Assessed by Optical Coherence Tomography Angiography
Published on: March 26, 2020
Optic nerve vasomotor effects of arterial blood gases
S Orgül1, G A Cioffi, D R Bacon
1Devers Eye Institute/Good Samaritan Hospital and Medical Center Portland, Oregon, U.S.A.
Purpose:
The purpose of this study was to examine the vasomotor effects of blood gases on the anterior optic nerve vascular bed. The microvasculature of the optic nerve was examined with intraluminal microvascular corrosion castings in six rabbits.
Methods:
The blood gases were varied by manipulating the ventilation rate for each rabbit prior to the intraluminal injection of the casting medium. The correlation between arterial blood gases (pO2, pCO2) and vasoconstriction of the arterioles supplying the anterior optic nerve was analyzed.
Results:
Relative constriction values of a total of 88 arterioles supplying the optic nerve of the six rabbits were obtained. A regression analysis provided a high and significant correlation between pCO2 and the average relative arteriolar constriction values for each rabbit (R = 0.86; t = -4.95; p = 0.008). The correlation between the arterial oxygen saturation and the average relative arteriolar constriction values was of borderline significance (R = 0.64; t = 2.65; p = 0.057).
Conclusion:
A strong interrelationship between arterial pCO2 and anterior optic nerve arteriolar constriction has been demonstrated.
Related Concept Videos
Chemical Factors Affecting Respiration Centers
CO2 has a potent influence on respiration and is strictly regulated. Under...
Blood Studies I: ABG and VBG
Arterial Blood Gas (ABG)
Arterial Blood Gas (ABG) studies are crucial for assessing the lungs' ability to supply oxygen and remove carbon dioxide, reflecting the patient's ventilation status. They also help understand the kidneys' capacity to reabsorb or...
Autoregulation of Blood Flow
Chemical Signaling in Autoregulation
Chemical signaling operates at the precapillary sphincter level, inciting either contraction or relaxation.
Neural Regulation of Blood Pressure
Baroreceptor Reflex
Baroreceptors, located in the carotid sinuses and aortic arch, detect changes in blood pressure. When blood pressure rises, these stretch-sensitive receptors...
Oxygen Transport in the Blood
Arteries of the Head and Neck
The internal carotid arteries supply blood to the anterior portion of the cerebrum. They enter the...

