Metamembrane #1: Boundary Issues
Anatomist's Corner
By Thomas Myers
Illustrations by Andrew Mannie
Originally published in Massage & Bodywork magazine, December/January 2004.
Copyright 2003. Associated Bodywork and Massage Professionals. All rights reserved.
Usually, because this is the Anatomist's Corner, we examine some aspect of our musculo-skeletal body, blowing it up larger than life and shedding some light on its intricacies. This round we're coming out of our corner and into the ring, swinging our "out-of-the-box"ing gloves! For this article we look at a grand concept, drawn from something that is too small to put our hands on. What are your cells sensing? And how can hands-on work affect the health of their sensory system? Safen your fasty belts (it's going to be bumpy ride), and let's start with the philosophy, and a bit of a rehash, of Biology 101.
The Mem-"brain"
Most of the trillions of cells in your body -- and most of the gazillions of cells in all the living creatures all over the world, right down to the single-celled blue green algae in the sea -- have three main elements. The first is a nucleus (or several nuclei) that reside in the "middle" of the cell, a very conservative biological stronghold housing the remarkably consistent but wildly knotted-up strands of DNA. DNA gets a lot of press these days as we map the human genome, but it has one basic job: It provides instructions for making varied and particular macro-proteins for use within, or sometimes outside, the cell (we'll talk more about this later).
This nucleus is surrounded and infused with the second element of most all cells, the cytoplasm (literally "cell juice"), a slightly gelled fluid that contains the organelles, like the Golgi apparatus, ribosomes and mitochondria, which do the cell's work. The cytoplasm circulates, providing a transport system to bring raw materials in from the edge of the cell toward the middle, and ribosomic messages from the DNA in the middle to tell the cell what to do with these raw materials. The cytoplasm then brings these finished goods and any waste products out to the edge to be exported.
Within the cytoplasm are also the fiber-like elements of the cytoskeleton, formerly called endoplasmic reticulum, which have come up for increasing study recently, and will be part of our discussion here and for the next column or two. These microtubules, microfilaments, chains of contractile myosin and actin proteins, and so-called focal adhesion molecules (glue) all contribute to the cell's ability to maintain and change its shape.
But every cell we know about also has to have a third basic element, and that is a membrane, and the nature of that membrane will occupy us for the rest of this article. (See Figure 1.)
First of all, cells are not the only things with membranes. Considered in its larger meaning, every thing in this world, if it is going to be a separable, identifiable thing, has to have some kind of membrane, a skin, a boundary. To be a thing in this world, there has to be an "inside the thing" part, and an "outside the thing" part -- the rest of the universe, or environment -- and there has to be some kind of surface that separates the inside from the outside. In a balloon, a box, a rock, a house or a car, this "membrane" concept is pretty obvious, but it is also true of more nebulous conceptual things like IBM, Harvard University, Iraq or your personality.
So, membranes are like boundaries, and as such they are more or less permeable depending on the situation. A rock's membrane doesn't allow much in or out at the best of times, but then a rock is pretty quiet company, sometimes to the point of being downright boring. A car's membrane allows air in and out, but has doors that are designed to let people pass in and out sometimes, and keep them from passing in or out at other times. So, while a rock's membrane is relatively impermeable, a car's membrane is "selectively" permeable, which is also a characteristic of biological membranes -- sometimes more permeable, sometimes less, and open to some things but closed to others.
Now Iraq and the New York Times have recently experienced boundary issues, where something got inside the membrane that they would rather have had outside. When that happens to you physically, you call it "sick" or even "poisoned," or in another domain we might call it "abused." Having good boundaries is important to mental health. In the body itself, maintaining good membranes is one of the keys to vibrant physical health. Really closed membranes, such as we have seen in Burma and North Korea, don't lead to a healthy economy. People have long argued whether the United States has "membranes" that are too permeable to immigration or not.
Having well-functioning membranes, however, is not the same as having well-defended membranes. For biological things, like us, a tree, the frog in the tree, the fly on the frog, and the bacteria on the fly, cell membranes need to be permeable enough to allow food in and waste out, but not so permeable that just anything can get in and out. In other words, without a selectively-permeable membrane, life would not last. If its boundaries are too permeable, everything would flow in and out too easily, and without any way to distinguish itself chemically from its environment, life would dissolve into the surrounding medium. If it is too impermeable, like a rock or Ebenezer Scrooge, life suffocates from lack of exchange.
Because of the crucial nature of membranes, life has spent quite a bit of energy building good ones. You are made up of trillions of cells and each of these cells has a tremendously complex membrane system. Noting just a couple of generalities about these membranes, we can see that most biological membranes are double layered, they have a variety of ways that things can get in and out, and they not only separate the inside and the outside, they also connect the inside with the outside.
Figure 2 demonstrates all three of these properties:
1) The cell membrane is always double layered, with the two protein layers being held apart by a dual phospholipid (fat) layer that repels against a layer of water, keeping the two layers from collapsing on each other. In other words, each cell is double-bagged, just like your groceries at Shop 'n' Spend.
2) Small molecules, like salt, can slip between the molecules of this double layer, following osmotic concentrations and other natural
passive chemical processes. So this basic part of the membrane is semi-permeable -- allowing small molecules to pass in and out, but without the ability to control how that movement happens. When you sit in the bath for a long time, your fingertips wrinkle up because the cells lose water via osmosis. Neither you nor those cells can stop that process by will.
3) The globular proteins, floating around in this sea of fat like large beach balls, are actually channels that have a key-like mechanism that can allow or prevent the passage in or out of the cell of the larger macromolecules. This process is highly selective, and varies with the state of the cell. The membrane is studded with thousands of these ligands (links) that bind it to the chemistry outside the cell, and also, as we shall see, tie it mechanically to the surrounding environment.
Selective Boundaries
Now, it is to the nature of these links that we turn our attention. I invite you to listen for the parallels with psychology and boundary issues in professional practice, but we'll try not to hit you over the head with the metaphor.
First let us look at the chemically-sensitive links. I am not a chemist, so a lot of this will be a little sketchy, but there are some references at the end for those who want to pursue the details. The "glob" (beach ball) part of the globular protein is just a shell. The mechanism inside it is a large and complex protein that looks something like two bits of seaweed at each end, sticking out of the beach ball, with a spirally spring section joining the two in the middle within the beach ball. The spirally bit is inside the shell, and the two bits of seaweed (actually a bit stiffer than seaweed -- somewhere between seaweed and broccoli) stick out: One end into the cytoplasm of the cell, the other end out into the surrounding fluid of the cell's environment.
The seaweed bits have sensors on the end ("docking stations") into which certain chemicals fit. Depending on how they fit, or how many there are docking in at any given time, they may encourage the spring in the middle to unwind and open, letting something through the membrane, or they may encourage ("cause" would be better -- the action is presumably chemical, not volitional) the spring to close, keeping any large molecules from passing through the membrane.
Notice that this can happen from the inside or from the outside, chemical stimulation of the sensors on the "seaweed" at either end, within the cell or from the outside environment, can cause a tightening or loosening of the pore through the globular shell.
Let's see how this works in practice. Neurotransmit-ters are an easy way to see the basic process. A neurotransmitter is released from one nerve and swims across the synapse to the dendrites of the next nerve in the sequence. The transmitter chemical fits into a receptor site on the "seaweed" of the next nerve, and causes it to be more or less likely to fire (open the membrane to an action potential).
The interaction can get quite complex. If the receptor sites on the outside of the cell detect something it recognizes as "food," then the spiral is more likely to open to let the food in. But if the receptor sites at the other end of the seaweed, inside the cell, are also already jammed with food -- meaning the cell is well-supplied -- then the stimulation from the outside will have less opening effect on the spring in the middle. If the food receptor sites are empty on the inside, the spring will open readily to admit the food from the outside environment into the digestive processes inside.
Something that's poisonous usually has an effect on the receptor sites, causing the membrane to close up, to keep out the poison. The most effective poisons mimic a body chemical that is more benign, and thus get in. New viruses can get in sometimes because the body has built no defenses up, but once they are built, the body has a more or less permanent resistance to that method of attack.
There are receptors for caffeine, nicotine, morphine, adrenaline and a few thousand other substances -- not all of them on every cell, of course, but some cells can "recognize" quite a number of different "messages" carried in the surrounding chemistry and react to them.
To read more about these links and the extraordinary story of how they affect us, both physically and emotionally, and how those effects can be enhanced via bodywork and massage, don't miss Molecules of Emotion, authored by the redoubtable pioneer, scientist and humanist Dr. Candace R. Pert. (See "For More Information" sidebar.)
But there is another class of proteins spanning the membrane with ends sticking into and outside the cell, called "integrins," and these serve a different purpose, creating a different sense for the cell. On the inside, the integrins link into the cytoskeleton -- the filaments and microtubules that hold the cell in shape. On the outside, the integrins link into the gluey ground substance and the collagen network of connective tissue. The integrins are not sorting through the chemistry as it passes by the cell membrane, they instead link the cell to its spatial environment, forming the mechanical links that keep the cell where it is in the body, or conversely allowing it to move.
There are often hundreds and sometimes thousands of these integrin links studded over the surface of any given cell. Each link is quite small and easily broken (explaining why they took so long to be noticed scientifically), but taken together, they add up, like the links in Velcro, to a strong network that keeps the cell in place, and keeps it in the proper shape. To move through the body, a cell must dissolve these integrin linkages behind it and forge new ones ahead.
Thus each cell is tuned in, in a mechanical linkage, all the way from the center of the cytoskeleton in the nucleus out to the whole network of collagen that permeates the body. (See Figures 3A and 3B.) This will form the basis for our next column, in which we will explore the organismic "metamembrane."
Athletic Proteins
To summarize our picture so far, we can see that the cell membrane is essentially a droplet of fat surrounding the inner workings of the cell, sealing it off from the outside world so that it can have a somewhat separate existence. Only "somewhat" because the fatty layer (along with the phosphates that coat it) allows some small chemicals -- salt, water, urea, etc. -- to slip in and out through it.
Floating in this sea of fat are two types of large protein complexes, each with different functions. We could imagine these globular proteins that span the membrane as athletic young people cinched into the membrane at their waist.
One set of these busy athletes is busily handling any molecules they can find in their vicinity. The ones they like, they pass through to the inside, the ones they find distasteful, they push away from the cell, or just close up tight and won't let them pass through. We have to imagine that these guys have prehensile feet, and they are doing much the same with their feet inside the cell, checking for inventory, noting the "yummies" and passing "yuckies" up and out of the cell.
The other set of proteins are performing a different function. They are tied to bungee cords around their ankles, and these bungee cords are anchored right into the middle of the cell. Their hands, outside the cell, are grabbing onto whatever nets and ropes they can find outside the cell. Sometimes they let go and get a purchase on another rope. (See Figure 4.)
These two kinds of molecules perform two major sensory functions for the cell, the first assesses and responds to the chemical environment while the second assesses and responds to the mechanical environment. In other words, each cell is constantly tasting its surroundings and feeling the tension there, too.
Both of these processes are essential to cell health, and both are affected, way down at that microscopic level, by our work up at the whole body level. Changing fluid flow and getting stuff moving around the cells alters the nature of the chemicals the cells are assessing. On a macro level, the chemistry released by a good bodywork session bathes these receptors in health-giving messenger molecules.
Changing spatial relationships within the body can alter wound-healing and even genetic expression within the cell, so that structural changes can produce unexpected physiological changes. More on all this next time.
Sophisticated Environment
So, I said I wouldn't hit you over the head with this metaphor, but how intelligent are your boundaries? Can you sort out what needs to be taken in from what should not? Can you eliminate the poisonous effectively? Are you linked in to the energetic space around you, able to respond and let go when necessary, and hang on when the going gets rough? All this kind of intelligence resides in your membranes, but we as individuals are sometimes not so sophisticated in our responses to our environment. Everything that I needed to know about how to maintain good practice boundaries I learned from my membranes.
Thomas Myers, Certified Advanced Rolfer, L.M.T., N.C.T.M.B., studied directly with Drs. Ida Rolf and Moshe Feldenkrais, and has practiced integrative bodywork for more than 25 years in a variety of cultural and clinical settings. Myers directs Kinesis, Inc., which develops and runs training courses internationally for manual and movement therapies. He served as a founding member of the NCBTMB and as a chair of the Rolf Institute's anatomy faculty. His articles have appeared in a number of magazines, and his book on myofascial continuities, Anatomy Trains: Myofascial Meridians for Manual and Movement Therapists, was published in 2001 by Harcourt Brace. Myers retains a strong interest in perinatal and developmental issues around movement. His practice combines structural integration, physiological rhythmic sensitivity and movement. He lives, writes and sails on the coast of Maine.
Originally published in Massage & Bodywork magazine, December/January 2004.
Copyright 2003. Associated Bodywork and Massage Professionals. All rights reserved.
Usually, because this is the Anatomist's Corner, we examine some aspect of our musculo-skeletal body, blowing it up larger than life and shedding some light on its intricacies. This round we're coming out of our corner and into the ring, swinging our "out-of-the-box"ing gloves! For this article we look at a grand concept, drawn from something that is too small to put our hands on. What are your cells sensing? And how can hands-on work affect the health of their sensory system? Safen your fasty belts (it's going to be bumpy ride), and let's start with the philosophy, and a bit of a rehash, of Biology 101.
The Mem-"brain"
Most of the trillions of cells in your body -- and most of the gazillions of cells in all the living creatures all over the world, right down to the single-celled blue green algae in the sea -- have three main elements. The first is a nucleus (or several nuclei) that reside in the "middle" of the cell, a very conservative biological stronghold housing the remarkably consistent but wildly knotted-up strands of DNA. DNA gets a lot of press these days as we map the human genome, but it has one basic job: It provides instructions for making varied and particular macro-proteins for use within, or sometimes outside, the cell (we'll talk more about this later).
This nucleus is surrounded and infused with the second element of most all cells, the cytoplasm (literally "cell juice"), a slightly gelled fluid that contains the organelles, like the Golgi apparatus, ribosomes and mitochondria, which do the cell's work. The cytoplasm circulates, providing a transport system to bring raw materials in from the edge of the cell toward the middle, and ribosomic messages from the DNA in the middle to tell the cell what to do with these raw materials. The cytoplasm then brings these finished goods and any waste products out to the edge to be exported.
Within the cytoplasm are also the fiber-like elements of the cytoskeleton, formerly called endoplasmic reticulum, which have come up for increasing study recently, and will be part of our discussion here and for the next column or two. These microtubules, microfilaments, chains of contractile myosin and actin proteins, and so-called focal adhesion molecules (glue) all contribute to the cell's ability to maintain and change its shape.
 Figure 1 |
First of all, cells are not the only things with membranes. Considered in its larger meaning, every thing in this world, if it is going to be a separable, identifiable thing, has to have some kind of membrane, a skin, a boundary. To be a thing in this world, there has to be an "inside the thing" part, and an "outside the thing" part -- the rest of the universe, or environment -- and there has to be some kind of surface that separates the inside from the outside. In a balloon, a box, a rock, a house or a car, this "membrane" concept is pretty obvious, but it is also true of more nebulous conceptual things like IBM, Harvard University, Iraq or your personality.
So, membranes are like boundaries, and as such they are more or less permeable depending on the situation. A rock's membrane doesn't allow much in or out at the best of times, but then a rock is pretty quiet company, sometimes to the point of being downright boring. A car's membrane allows air in and out, but has doors that are designed to let people pass in and out sometimes, and keep them from passing in or out at other times. So, while a rock's membrane is relatively impermeable, a car's membrane is "selectively" permeable, which is also a characteristic of biological membranes -- sometimes more permeable, sometimes less, and open to some things but closed to others.
Now Iraq and the New York Times have recently experienced boundary issues, where something got inside the membrane that they would rather have had outside. When that happens to you physically, you call it "sick" or even "poisoned," or in another domain we might call it "abused." Having good boundaries is important to mental health. In the body itself, maintaining good membranes is one of the keys to vibrant physical health. Really closed membranes, such as we have seen in Burma and North Korea, don't lead to a healthy economy. People have long argued whether the United States has "membranes" that are too permeable to immigration or not.
Having well-functioning membranes, however, is not the same as having well-defended membranes. For biological things, like us, a tree, the frog in the tree, the fly on the frog, and the bacteria on the fly, cell membranes need to be permeable enough to allow food in and waste out, but not so permeable that just anything can get in and out. In other words, without a selectively-permeable membrane, life would not last. If its boundaries are too permeable, everything would flow in and out too easily, and without any way to distinguish itself chemically from its environment, life would dissolve into the surrounding medium. If it is too impermeable, like a rock or Ebenezer Scrooge, life suffocates from lack of exchange.
Because of the crucial nature of membranes, life has spent quite a bit of energy building good ones. You are made up of trillions of cells and each of these cells has a tremendously complex membrane system. Noting just a couple of generalities about these membranes, we can see that most biological membranes are double layered, they have a variety of ways that things can get in and out, and they not only separate the inside and the outside, they also connect the inside with the outside.
 Figure 2 |
1) The cell membrane is always double layered, with the two protein layers being held apart by a dual phospholipid (fat) layer that repels against a layer of water, keeping the two layers from collapsing on each other. In other words, each cell is double-bagged, just like your groceries at Shop 'n' Spend.
2) Small molecules, like salt, can slip between the molecules of this double layer, following osmotic concentrations and other natural
passive chemical processes. So this basic part of the membrane is semi-permeable -- allowing small molecules to pass in and out, but without the ability to control how that movement happens. When you sit in the bath for a long time, your fingertips wrinkle up because the cells lose water via osmosis. Neither you nor those cells can stop that process by will.
3) The globular proteins, floating around in this sea of fat like large beach balls, are actually channels that have a key-like mechanism that can allow or prevent the passage in or out of the cell of the larger macromolecules. This process is highly selective, and varies with the state of the cell. The membrane is studded with thousands of these ligands (links) that bind it to the chemistry outside the cell, and also, as we shall see, tie it mechanically to the surrounding environment.
Selective Boundaries
Now, it is to the nature of these links that we turn our attention. I invite you to listen for the parallels with psychology and boundary issues in professional practice, but we'll try not to hit you over the head with the metaphor.
First let us look at the chemically-sensitive links. I am not a chemist, so a lot of this will be a little sketchy, but there are some references at the end for those who want to pursue the details. The "glob" (beach ball) part of the globular protein is just a shell. The mechanism inside it is a large and complex protein that looks something like two bits of seaweed at each end, sticking out of the beach ball, with a spirally spring section joining the two in the middle within the beach ball. The spirally bit is inside the shell, and the two bits of seaweed (actually a bit stiffer than seaweed -- somewhere between seaweed and broccoli) stick out: One end into the cytoplasm of the cell, the other end out into the surrounding fluid of the cell's environment.
The seaweed bits have sensors on the end ("docking stations") into which certain chemicals fit. Depending on how they fit, or how many there are docking in at any given time, they may encourage the spring in the middle to unwind and open, letting something through the membrane, or they may encourage ("cause" would be better -- the action is presumably chemical, not volitional) the spring to close, keeping any large molecules from passing through the membrane.
Notice that this can happen from the inside or from the outside, chemical stimulation of the sensors on the "seaweed" at either end, within the cell or from the outside environment, can cause a tightening or loosening of the pore through the globular shell.
Let's see how this works in practice. Neurotransmit-ters are an easy way to see the basic process. A neurotransmitter is released from one nerve and swims across the synapse to the dendrites of the next nerve in the sequence. The transmitter chemical fits into a receptor site on the "seaweed" of the next nerve, and causes it to be more or less likely to fire (open the membrane to an action potential).
The interaction can get quite complex. If the receptor sites on the outside of the cell detect something it recognizes as "food," then the spiral is more likely to open to let the food in. But if the receptor sites at the other end of the seaweed, inside the cell, are also already jammed with food -- meaning the cell is well-supplied -- then the stimulation from the outside will have less opening effect on the spring in the middle. If the food receptor sites are empty on the inside, the spring will open readily to admit the food from the outside environment into the digestive processes inside.
Something that's poisonous usually has an effect on the receptor sites, causing the membrane to close up, to keep out the poison. The most effective poisons mimic a body chemical that is more benign, and thus get in. New viruses can get in sometimes because the body has built no defenses up, but once they are built, the body has a more or less permanent resistance to that method of attack.
There are receptors for caffeine, nicotine, morphine, adrenaline and a few thousand other substances -- not all of them on every cell, of course, but some cells can "recognize" quite a number of different "messages" carried in the surrounding chemistry and react to them.
To read more about these links and the extraordinary story of how they affect us, both physically and emotionally, and how those effects can be enhanced via bodywork and massage, don't miss Molecules of Emotion, authored by the redoubtable pioneer, scientist and humanist Dr. Candace R. Pert. (See "For More Information" sidebar.)
But there is another class of proteins spanning the membrane with ends sticking into and outside the cell, called "integrins," and these serve a different purpose, creating a different sense for the cell. On the inside, the integrins link into the cytoskeleton -- the filaments and microtubules that hold the cell in shape. On the outside, the integrins link into the gluey ground substance and the collagen network of connective tissue. The integrins are not sorting through the chemistry as it passes by the cell membrane, they instead link the cell to its spatial environment, forming the mechanical links that keep the cell where it is in the body, or conversely allowing it to move.
 Figure 3A: The old model of cellular function saw each cell as functioning independently, like a ship in the sea. |
 Figure 3B: Newer research reveals the cell to be strongly connected from its very middle out into the body as a whole, more like a series of flies stuck in a spider web. |
Thus each cell is tuned in, in a mechanical linkage, all the way from the center of the cytoskeleton in the nucleus out to the whole network of collagen that permeates the body. (See Figures 3A and 3B.) This will form the basis for our next column, in which we will explore the organismic "metamembrane."
Athletic Proteins
To summarize our picture so far, we can see that the cell membrane is essentially a droplet of fat surrounding the inner workings of the cell, sealing it off from the outside world so that it can have a somewhat separate existence. Only "somewhat" because the fatty layer (along with the phosphates that coat it) allows some small chemicals -- salt, water, urea, etc. -- to slip in and out through it.
Floating in this sea of fat are two types of large protein complexes, each with different functions. We could imagine these globular proteins that span the membrane as athletic young people cinched into the membrane at their waist.
One set of these busy athletes is busily handling any molecules they can find in their vicinity. The ones they like, they pass through to the inside, the ones they find distasteful, they push away from the cell, or just close up tight and won't let them pass through. We have to imagine that these guys have prehensile feet, and they are doing much the same with their feet inside the cell, checking for inventory, noting the "yummies" and passing "yuckies" up and out of the cell.
 Figure 4: The two kinds of proteins that span the cell membrane can be thought of as two different kinds of athletes cinched into the membranes at their waists. One set are busy sorting whatever molecules and substances pass near the cell's membrane, and passing the beneficial ones in or out. The other set are tied to bungee cords that connect the very center of the cell to the body as a whole. |
These two kinds of molecules perform two major sensory functions for the cell, the first assesses and responds to the chemical environment while the second assesses and responds to the mechanical environment. In other words, each cell is constantly tasting its surroundings and feeling the tension there, too.
Both of these processes are essential to cell health, and both are affected, way down at that microscopic level, by our work up at the whole body level. Changing fluid flow and getting stuff moving around the cells alters the nature of the chemicals the cells are assessing. On a macro level, the chemistry released by a good bodywork session bathes these receptors in health-giving messenger molecules.
Changing spatial relationships within the body can alter wound-healing and even genetic expression within the cell, so that structural changes can produce unexpected physiological changes. More on all this next time.
Sophisticated Environment
So, I said I wouldn't hit you over the head with this metaphor, but how intelligent are your boundaries? Can you sort out what needs to be taken in from what should not? Can you eliminate the poisonous effectively? Are you linked in to the energetic space around you, able to respond and let go when necessary, and hang on when the going gets rough? All this kind of intelligence resides in your membranes, but we as individuals are sometimes not so sophisticated in our responses to our environment. Everything that I needed to know about how to maintain good practice boundaries I learned from my membranes.
Thomas Myers, Certified Advanced Rolfer, L.M.T., N.C.T.M.B., studied directly with Drs. Ida Rolf and Moshe Feldenkrais, and has practiced integrative bodywork for more than 25 years in a variety of cultural and clinical settings. Myers directs Kinesis, Inc., which develops and runs training courses internationally for manual and movement therapies. He served as a founding member of the NCBTMB and as a chair of the Rolf Institute's anatomy faculty. His articles have appeared in a number of magazines, and his book on myofascial continuities, Anatomy Trains: Myofascial Meridians for Manual and Movement Therapists, was published in 2001 by Harcourt Brace. Myers retains a strong interest in perinatal and developmental issues around movement. His practice combines structural integration, physiological rhythmic sensitivity and movement. He lives, writes and sails on the coast of Maine.
