The Liver – Just Another Normal Miracle of the Body
The liver is the largest gland in the body and is central to many metabolic functions. It is known as the body’s “metabolic warehouse.”
The liver serves several important functions. It is integral to the digestive system, producing both internal and external secretions. The external secretion, bile, aids in the digestive process, while internal secretions are responsible for the metabolism of both nitrogenous and carbohydrate materials absorbed from the intestine.
One of the unique structural features of the liver is its dual blood supply. It is supplied both by an artery (hepatic artery) and a vein (yes a vein!) – the portal vein. The portal vein drains the gastrointestinal tract of digested metabolic products and transports the nutrients to the liver for processing.
The Cells
Hepatocytes are the major cellular component of the liver, comprising approximately 70% by volume. Structurally they are characterised by their large size and the absence of a basement membrane. Functionally they are characterised by their remarkable metabolic and regenerative capability. Kupffer cells are found within the space of Disse and they act as macrophages of the liver, identifying and removing substances and organisms toxic to the body.
The AiA rendering of cells in the round provide an image that is reminiscent of craters on the moon surface. The thought process behind the image is the formation of tissues from cells. The building of the whole from the parts starts with the cell and progresses to the tissue and finally the organ. In this instance, groups of liver cells are artistically combined to form a tissue and an imaginary spherical organ.
Cellular Organization
Organization of the Liver Cells in Cords Along the Rivers of Blood Flow
The liver is a compound tubular serous gland. The cells are arranged in plates or cords alongside rivulets of a capillary network called sinusoids. The spaces of Disse are spaces below the lining of the Kupffer cells. The plates and cords are lined by the sinusoids which are the channels which carry blood to the liver. Just below the sinusoids, between the wall of the sinusoid and the capsule of the liver there is a space called the space of Disse which carries the lymphatic fluid of the liver.
Organization of the Liver Cells in Cords in the Liver Lobule
The cells of the liver are organized in cords and plates and are organized like spokes of a wheel around the central vein. The periphery of the lobule contains groups of portal triads consisting of portal vein (dark blue), hepatic artery (red) and bile duct (green).
The structural liver unit is called a lobule. Cellular plates branch and anastomose alongside and in parallel with the sinusoids. Each lobule measures 1-2mm and is shaped like a hexagon. A central venule lies at the center of the lobule and is the destination of the sinusoids, which carry both hepatic arteriole as well as portal venous blood. At the periphery of the lobules are sets of portal triads consisting of portal vein, bile duct and hepatic artery. The biliary system collects bile from the liver and evolves into an independent network terminating in the common bile duct which empties bile, into the duodenum. The hepatic artery and portal vein supply the liver with metabolic substrates via the sinusoids, and also collect metabolic products produced by the liver to transport to the rest of the body.
Anatomy of the Liver in a Nutshell–
From its Embryonic Beginnings to Full Member of the Society of the Body
Pleasure
Alcohol – Drink of the Gods in Moderation and Poison of the Devil in Excess
Anatomy of the Initial Positive Effects of Alcohol
“Drink because you are happy, but never because you are miserable.”
― G.K. Chesterton,
Social Drinking: The Prostate Having a Drink with the Uterus
The uterus and prostate are out on a date and sharing a cocktail The uterus approximates a rectangular shape as does the prostate, accounting for their fascination with each other and their similarity with the shape of the wine glass. The uterus is accompanied by the ovaries and the vagina which forms the stem of the wine glass. The prostate is accompanied by the Seminal vesicles and Cowper’s glands and the urethra which acts as the stem of the wine glass. The male secretion seen in the urethra consists of a mixture of sperm, prostatic secretions, and seminal vesicle secretions.
Social drinking to celebrate an event is a wonderful means to enable people to open up to each other
As G.K. Chesterton wrote – “Drink because you are happy, but never because you are miserable.”
William Shakespeare, in Othello, on the other hand wrote – “I would not put a thief in my mouth to steal my brains.”
Most cultures favor the use of alcohol in celebration of events, and the positive effects of alcohol when used judiciously is to promote a pleasurable feeling via the nucleus accumbens, and to reduce stressful feelings (often social interactions) by reducing inhibitions by acting on the amygdala
Anatomy of the Feeling of Pleasure and the Nucleus Accumbens
The nucleus accumbens is one of the most primitive part of the brain. It is part of the basal part of the forebrain. It is a paired structure. Alcohol promotes pleasure by stimulating the nucleus accumbens.
The Nucleus Accumbens
The coronal section of the brain shows the nucleus accumbens (ringed red) opposite its partner at the base of the brain. It lies just inferior to the internal capsule and frontal horns, near the hypoyhalamus
Courtesy Department of Anatomy and Neurobiology at Boston University School of Medicine Dr. Jennifer Luebke , and Dr. Douglas Rosene
Artistic Rendition of the Nucleus Accumbens on a sagittal T1 Weighted MRI
The nucleus accumbens, which is the site enabling the sensation of pleasure is shown as a red dot at the base of brain near the hypothalamus.
Stress
Anatomy of Stress and the Amygdala
The amygdalae are paired structures that are part of the limbic system that play an important part in emotional reactions including the reactions to stress. Alcohol reduces the uncomfortable emotion of stress and distress. Stress, in general is healthy, while distress on the other hand is not. The distinction between the two is not always obvious. Social situations are often stressful since in general people are “forced”into a position with “new” people they do not know too well. Using alcohol in such a social situation disinhibits the individuals, reduces the feeling of stress and promotes a sense of social confidence.. The origin of the physiology is in the amygdala.
Amygdala of the Forebrain in Sagittal Projection
The amygdala (red arrow)is a nucleus that is part of the limbic system. It is a paired structure. They are located deep in the temporal lobes and participate in emotional reactions, memory, and decision making.
Peer Pressure
Stressful social situations are particularly prominent in adolescence when peer pressure is pervasive. The college experience with new adventures of socialization, combined with freedom from the constraints of paternal disciplines are ripe for the use of substance abuse.
The scene: Party night – adolescent on the right, different innocent, alone and anxious. The in- crowd on the left are homogenous, powerful in number and stature, and encourage the newcomer to join in and be “one of us” – perhaps drink or smoke – and this is how it starts.
Educate, support, and love your children – Promote confidence in themselves so when they are confronted they can just say “no!”
Loneliness
Alone and bored, some turn to alcohol to provide relief. It is a short term, and short sighted relief to the problem
Early Addiction
Every form of addiction is bad, no matter whether the narcotic be alcohol or morphine or idealism.
The signs of early addiction
There are a few early warning signs that are forebears of early addiction as they start to surface.
They include; drinking alone, hiding and lying about the habit, blacking out, neglecting responsibility, deteriorating relationships, drinking in dangerous circumstances (eg before driving) and inability to quit.
Too Much of a Good Thing- can make your life tipsy turvy and turn you upside down –
shows bottles of alcohol in different positions and personify the state of inebriation. Alcoholic intoxication is a form of poisoning, and can make your life tipsy turvy and turn you upside down. The art piece expresses the uncontrolled situation of inebriation. When the liver cannot metabolize the alcohol due to excess in the blood stream drunkenness ensues. At lower blood levels there is a sensation of elation and lack of social reserve. With higher levels of alcohol in the blood, cerebral and cerebellar dysfunction ensues with ataxia, imbalance and muscle incoordination. Forebrain impairment includes disability to make appropriate decisions. Coma and death can ensue when blood levels are extremely high.
A drunk man in the town plaza is toying with the idea of another swig. His indifference to his environment, and lack of judgement suggests he is inebriated. However his body language with an outstretched arm holding the bottle and the other hand pointed in another direction may suggest, at least idealistically, symbolically and hopefully subconsciously, that he realises he could go one of two ways “Decision time” he says to himself – “on the one hand I could take a swig .. Yet on the other I may take a different and more healthful course” Which way do you think he would go? (Photograph modified to enable anonymity)
Cirrhosis
The left sided image shows the CT scan of a normal liver. The liver is the biggest structure that you can appreciate on the CT scan and is triangular in shape. The scan on the right shows a liver with cirrhosis. Alcohol pickles and scars the liver making it look like a knobby shrunken prune. The first image reflects healthy and romantic enjoyment of two people enjoying a beer at sunset. The colorful sunset transposes int a black and white background providing the mood of a lonely alcoholic. The alcoholic drinks in loneliness and in excess, until finally the person and the the bottle do not remain upright symbolically reflecting physical and psychosocial failure.
The Failing Liver
Normal Liver and Cirrhosis and Ascites
The AiA rendering shows a normal liver on the left, and a person with cirrhosis on the right evidenced by a shrunken, knobbly and pickled liver, jaundice of the skin and a distended abdomen caused by the accumulation of litres of fluid (ascites). In the long run, the addiction results in much suffering, a miserable existence, and immediately life threatening hemorrhagic episodes.
(Photograph modified to enable anonymity)
Liver Cancer
Liver cancer, frequently arises as a complication of cirrhosis and most particularly from alcoholic cirrhosis. The AiA rendering of the liver shows the inner workings of the organ, now inhibited by the large yellow cancer preventing the clockwork function of the liver. The liver starts to fail as a result of the cirrhosis so that the synthesis of biochemical products that keep the body going are no longer produced to the degree which they are needed.
The collage shows normal healthy liver cells (top left) with a healthy appearing torso (CT scan reconstruction bottom left). The top right image reflect cancerous hepatic cells where the nuclear to cytoplasmic ratio is too large meaning that the the nuclei are too big and the cytoplasm too scanty. This finding is one of the typical findings in cancer. An emaciated torso (bottom right) is seen in contrast to the healthy counterpart.
Artistically the stark reality of health and disease is exposed. This terrible disease stares at us in stark graphic reality.
Philosophically – the cancer cell is like a rebel in the community, who only has selfish interests and contributes nothing to the welfare of the community. As a result the whole community of the body eventually fails, and hence the emaciation of the body.
Lessons? Kick the Habit Early or Kick the Bucket
