How your capillaries help blood flow

The heart isn’t the sole driver of the circulation. It is supported by a complementary driving mechanism situated in the capillaries. How do these fragile, hair-thin, vessels help the heart- muscle in propelling the flow of blood system and keep on doing that after the heart has stopped? And, how do Masquelier’s OPCs help this mechanism?
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If your heart is really the unique “driver” of the blood that circulates through your arteries, capillaries and veins, how do we explain the phenomenon that blood flow has been observed in mice, rats, dogs, and chick after the heart stopped beating? What was it that made the ‘postmorten’ flow persist from 15 minutes to several hours? And, how do we explain the mystery that in humans, when the heart has stopped, the arteries are found empty of blood and filled with air? Which is, by the way, the reason why the ancient Greeks, when they discovered this curious phenomenon while performing autopsies, named this part of the circulatory system “artēríā” (ᾰ̓ρτηρῐ́ᾱ), which means: ‘air-duct’ or ‘windpipe’.

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“On the Driver of Blood Circulation Beyond the Heart” is the title of a scientific article in which researchers Zheng Li and Gerald Pollack raised and answered the question that was aked by generations of established physicians and physiologists since the 19th century: “could the heart be the sole driver of the circulation?” The consensus among those scientists was that “a complementary driving mechanism must exist in blood vessels, presumably in the capillaries.” (i) Sounds quite plausible, but, without themselves being capable of exerting the slightest mechanical pressure, how could those tiny, fragile, hair-thin micro-vessels help the robust heart-muscle in propelling the flow of blood through the circulatory system and keep on doing that after the heart has stopped? To answer this question we must explore a curious property of … water.

While fluid commonly flows in response to an external pressure, it so happened that Li and Pollack had observed in earlier experiments a “flow-driving mechanism” that propels water in small tubular “tunnels” or tiny “tubes” without imposed pressure. (ii) They were able to measure this spontaneous flow in a cone-shaped “tunnel” they had “pierced” through a “block” of an insoluble, thick, compact substance called “hydrogel”. When such a “hydrogel-block” was placed in a container filled with pure water, the water began to flow from the narrow to the wider end of the tunnel. The flow could be accelerated by exposing this set-up to infrared energy. Apparently, energy (warmth) acted as the fuel that could somehow be converted into the water’s “self-driving” motion. 

This is not the place to explore in the very technical terms used by Li and Pollack what causes this conversion. But, in the simplest and briefest of terms, it has to do with the fact that water has more than 3 appearances. Other than manifesting itself as vapor, liquid or solid (frozen), it is capable of assuming a so-called 4th phase in which water has the “liquid-solid” properties of a gel. As explained in my blogpost OPCs and the Fluid Matrix of Water, (iii) we are all familiar with 4th-Phase water’s “jelly” properties when we consume or prepare Jell-O, which becomes a gel when liquid water spontaneously turns into 4th-Phase water. All that is needed for this conversion is that the water comes in contact with gelatin proteins or similar substances. In Collagen, OPCs and Crystal Body Consciousness, I explained that the same conversion takes place in your body when water comes in contact with a surface that contains collagen. On this surface, water forms a thin “jelly” zone. (iv)

Please note that, although 4th-Phase water behaves like a gel, 4th-Phase water is nothing but “jelly” water that is distinct from the various “hydrogels” that were tested by Li and Pollack in the water-hydrogel-tunnel set-up. What interests us is that one of those “hydrogels” was collagen. In the presence of a sufficient amount of warmth, a thin “zone” of 4th-Phase water was formed at the inner surface of the “collagen-tunnel”. In the context of cardiovascular health, this is extremely relevant because, as explained elsewhere, in the human body, all the vessels of the circulatory system are “coated” with an inner “lining” that consists of a single layer of cells that are “embedded” in collagen. It’s called: the endothelium. Due to the interaction between the blood’s fluid (the “serum”) and the endothelium’s collagen, a zone of 4th-Phase water is formed on the endothelium’s surface. The capillaries form the narrowest (“hair thin”) section in the vascular system and it is there that the vascular wall consists of no more than the endothelium. As a consequence, the lumen of the vessel, i.e. the inner open space enclosed by the 4th-Phase water zone that “coats” the endothelium’s surface is also at its narrowest in the capillaries. 

Yes, fine, but how is it that this creates a movement of the water toward the wider end of a “collagen-tunnel”? Well, to begin with, when 4th-Phase water is formed, the water molecules that are in contact with the collagen’s surface, first break apart and then coalesce to form the highly ordered, negatively charged film or “zone” adjacent to the surface while releasing positively charged particles (hydrogen atoms). In a thin tube, the hydrogen atoms then “collect” in the core of the tube. In our case, they collect in the core of the blood vessels. In the words of Li and Pollack, “the core thereby acquires high positive charge.” Because capillaries are much thinner that the adjoining arteries and veins, the concentration of the collected hydrogen atoms will be highest in the lumen of the capillary. Hence, the positive charge in the capillary will be higher than in the adjoining artery and vein. This difference in potential “density” will cause the blood to flow, but how, then, is it that, in the circulatory system, the direction of this flow is toward the vein and not back to the artery?

Li and Pollack explain that solving the issue of flow direction should rest principally with “the architecture” of the vascular network. In the vascular system, each “branch” or trajectory (artery, capillary, vein) has “a set of vessels with similar diameter”. Remember that in the above mentioned water-hydrogel-tunnel experiment, water spontaneously moved from the thinner to the wider end of the cone-shaped “tunnel”. Likewise, so Li and Pollack, “capillary flow should depend on the relative size of input and output vessels. Arterioles [the narrowing ends of the arteries at one end of the capillaries] have a narrower average diameter than venules [the widening beginnings of the veins at the other end of the capillaries] – approximately one third of venule diameter. For a capillary bed lying in between arterioles and venules, then, the blood should flow from narrower arterioles to wider venules. The predicted blood flow direction should therefore follow its natural direction in capillaries. It should also do so in veins, where the natural progression is from narrower to wider.”

To conclusively test this model, the researchers had to arrest the heart in a living organism. For this purpose, they sacrificed a living, intact, three-day old chick-embryo. When they stopped the embryo’s heart, they found exactly what they had predicted. Blood kept flowing from the capillaries into the veins. What’s more, the flow-model was “doubly” confirmed when they observed that “the predicted flow in arteries was opposite to the natural.” The blood began flowing back to the heart, because the size of the artery is wider at the end of the heart than at the periphery. “As the model predicted, the flow in the large, near-heart arteries was indeed opposite to the natural direction just after the heart stopped beating. […] As the non-beating heart stopped replenishing blood to the arteries, ultimately, the arteries emptied. The emptied arteries indicate that the flow-driving capacity of capillaries and veins exceeds that of the arteries. Thus, all blood vessels drive the blood towards the natural direction.” In the simplest of terms, the heart fills the arteries while the capillaries fill the veins.

In their “On the Driver of Blood Circulation Beyond the Heart” article, the authors explained that, in line with what they had observed in the water-hydrogel-tunnel experiment, the fuel for the capillaries’ flow-driving capacity lies in infrared energy. In the human body, this energy emerges naturally from metabolic heat, as well as from external sources such as sunshine. “For any organism”, so Li and Pollack, “the most fundamental requirement is metabolism. Metabolic activity generates heat. The heat is released in the form of [infrared] energy, which can drive flow and hence nourish the tissues. Thus, metabolism facilitates the circulation, while the circulation facilitates metabolism. The two phenomena enable one another. Appreciating the existence of this second circulatory driver [metabolic energy] opens the door to fresh understanding of cardiovascular disease, as well as to unforeseen therapies for combatting that disease. Thus, we may anticipate novel therapies appearing in the future.” 

With due respect to Li and Pollack’s work and the hope they place on “novel therapies”, allow me to point out that there’s an “old” natural remedy that perfectly fits their ground-breaking flow-model. Numerous pertinent human, animal and cell studies strongly support the fact that Masquelier’s OPCs can help maintain healthy microvascular structures and functions by positively acting on the microvasculature’s self-maintaining capacities. OPCs do this by supporting the constituent network of the microvascular wall by protecting collagen and elastin fibers against degradation as well as enhancing the synthesis of collagen and by combating inflammation and oxidative stress. This rich body of knowledge concerning the numerous cardiovascular benefits of Masquelier’s OPCs opens the door to appreciating these bioactives as vitally important in the microvasculature’s flow-driving capacity to assist the heart in driving the flow of blood. In terms of circulation and metabolism, Masquelier’s OPCs play an essential role in assisting the cardiovascular system to facilitate the body’s metabolism so that the energy can be produced that is required to fuel the circulation that facilitates metabolism so that the energy can be produced that is required to … keep the “circle of life” going.

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[i] On the Driver of Blood Circulation Beyond the Heart; Zheng Li, PhD and Gerald H. Pollack, PhD; Department of Bioengineering, University of Washington, Seattle, Washington, USA.; Posted on pre-print server bioRxiv; April 20, 2021; 
[ii] Surface-induced flow: A natural microscopic engine using infrared energy as fuel; Zheng Li and Gerald H. Pollack; Science Advances | Research article; 8 May 2020.
[iii] See blogpost/article OPCs and the Fluid Matrix of Water;
[iv] See blogpost/article Collagen, OPCs and Crystal Body Consciousness;