home Thyroid The liver is normal histology. Hepatic lobule: structure and functions. Educational video on the anatomy of the liver, structure and diagram of the hepatic lobule

The liver is normal histology. Hepatic lobule: structure and functions. Educational video on the anatomy of the liver, structure and diagram of the hepatic lobule

This is a large (up to 1.5 kg) vital organ. Performs the following functions:

1. secretory - secretes bile (a specific secretion of liver cells). It causes emulsification of fats, promoting further breakdown of fat molecules. Strengthens peristalsis.

2. Neutralizing (detoxification). Performed only by the liver. It uses complex biochemical mechanisms to neutralize toxins and medications formed during the digestion process.

3. Protective is associated with the activity of special cells - liver macrophages (Kupffer cells). They phagocytose various microorganisms, suspended particles that enter the liver through the bloodstream.

4. Synthesizes and accumulates glycogen - glycogen-forming function. Hepatic epithelial cells synthesize glycogen from glucose and deposit it in the cytoplasm. The liver is a glycogen depot.

5. Synthetic - synthesis of the most important blood proteins (prothrombin, fibrinogen, albumin).

6. Cholesterol metabolism.

7. Deposition of fat-soluble vitamins (A, D, E, K).

8. Blood deposition.

9. The liver is one of the most important hematopoietic organs. This is where blood formation in the fetus first begins. Then this function is lost, but in cases of disease of the hematopoietic organs, ectopic foci of hematopoiesis are formed in the liver.

DEVELOPMENT.

It develops from 3 rudiments - intestinal ectoderm, mesenchyme and neural rudiment. Formation begins at the end of the 3rd week of embryogenesis. A protrusion appears in the ventral wall of the 12 duodenum of the embryo - the hepatic bay. From it comes the development of the liver and gall bladder.

STRUCTURE. Associated with multiple functions. Externally, the liver is covered with a connective tissue capsule, from which septa extend. The organ is divided into lobes, in which the structural and functional unit of the liver is distinguished. There are several types of these units:

classic liver lobule

portal hepatic lobule

hepatic acinus

Classic liver lobule. Hexagonal in shape, prismatic, tapering towards the apex. Up to 1.5 cm at the base. The hepatic lobules form into a complex vessel - the central vein. Around it are the components of the lobule - the hepatic beams and intralobular sinusoidal capillaries. In some animals, interlobular connective tissue is very well defined. In the liver it is weakly expressed in normal conditions. The boundaries of the hepatic lobules are not clearly defined. In total, the liver contains approximately 500 thousand lobules.

BLOOD SUPPLY.

The liver is supplied with blood from two blood vessels. The gates of the liver include the raven vein (blood from the unpaired abdominal organs) and the hepatic artery (supply to the liver). Upon entering the gate, these vessels are arranged into smaller branches. The venous branches accompany the arterial branches throughout. Lobar veins and arteries are divided into segmental veins and arteries, interlobular veins and arteries (located parallel to the long axis of the lobule) - intralobular veins and arteries (surround the lobule on the periphery) - capillaries. at the periphery of the lobule, arterial and venous capillaries merge. As a result, an intralobular (sinusoidal) capillary is formed. He has mixed blood. These capillaries are located radially in the lobule and merge in the center, flowing into the central vein. The central vein passes into the sublobular vein (collector) - hepatic veins (3 and 4 pieces), which exit from the portal of the liver.

Thus, in the circulatory system of the liver, 3 sections can be distinguished:

1. blood flow system to the lobule. Represented by the portal vein and artery, lobar, segmental, interlobular, perilobular veins and arteries.

2. Blood circulation system in the lobule. It is represented by intralobular sinusoidal capillaries.

3. System of blood outflow from the lobule. Represented by the central vein, sublobular and hepatic veins.

In the liver there is a system of 2 veins: the portal vein - represented by the portal vein and its branches to the intralobular capillary; hepatic vein - represented by the central vein, sublobular and hepatic veins.

The structure of the classic lobule of the liver.

Educated:

1. hepatic beams

2. intralobular sinusoidal capillary.

The hepatic lobule is located radially. Formed in mammals and humans by 2 rows of epithelial liver cells - hepatocytes. These are large cells, polygonal in shape with a spherical nucleus in the center (20% of cells are binucleate). Liver cells are characterized by the content of polyploid nuclei (of various sizes). The cytoplasm of hepatocytes contains all organelles - granular and agranular cytoplasmic reticulum, mitochondria, lysosomes, peroxisomes, lamellar complex. There are also various inclusions - glycogen, fat, various pigments - lipofuscin, etc. In the center of the hepatic beam, between 2 rows of liver cells there is a bile capillary. It begins blindly in the center of the lobule and gives off short blind branches. At the periphery, the capillary passes into a short tube - the cholangiole, and then into the interlobular bile duct. Hepatocytes secrete bile into the bile capillary. The hepatic beam is a very specific terminal secretory section of the liver.

The bile capillary does not have its own wall; it is an expanded intercellular gap, which is formed by the cytolemma of adjacent hepatocytes with numerous microvilli. The contacting surfaces form endplates. Normally, they are very strong and bile cannot penetrate into the surrounding space. If the integrity of hepatocytes is compromised (for example, with jaundice), then bile enters the blood - a yellowish coloration of the tissues.

Cholangiola has its own lining, which is formed by a small number of oval-shaped cells (epithelial cells). On a cross section, 2-3 cells are visible.

The interlobular bile duct is located on the periphery of the lobule. It is lined with single-layer cubic epithelium. The cells of this epithelium are cholangiocytes. Each liver cell is both exocrine (produces bile) and endocrine (produces proteins, urea, lipids, and glucose into the blood). Therefore, the cell has 2 poles - biliary (where the bile capillary is located) and vascular (facing the blood vessel).

The hemocapillary is intralobular (sinusoidal). Has its own wall: structural features:

1. The lining is represented by several types of cells:

· endothelial cells - porous and fenestrated (pores and fenestrae are dynamic formations).

Liver macrophages (Kupffer cells), stellate reticuloendotheliocytes). Located between endothelial cells. Their surface forms numerous pseudopodia. These cells can be released from intercellular connections and travel with the bloodstream. They originate from blood stem cells - cells of the monocytic series. Capable of accumulating various suspended particles and microorganisms.

· Fat-accumulating cells (liver lipocytes). There are not many of them. their cytoplasm contains many fat vacuoles that never fuse. They accumulate fat-soluble vitamins.

· Pit cells (from English pockmarked). Their cytoplasm contains many secretory granules of various colors. These are endocrine cells. They are located on a discontinuous basement membrane, which is clearly expressed in the peripheral and central parts of the lobules.

Lesson 34. LIVER

Purpose of the lesson: to study the anatomical and histological structure of the liver.

Materials and equipment. Anatomical preparations: liver of cattle, horses and pigs. Histological preparations: pig liver (61). Tables and transparencies: histological structure of the liver, its lobules and plates, ultrastructure of the hepatocyte.

The liver - hepar - is the largest gland in the body (Fig. 84). It neutralizes exogenous and endogenous toxic substances, phagocytoses microorganisms and foreign particles, participates in protein, carbohydrate, fat, vitamin and other metabolisms, and forms bile. During the embryonic period, hematopoiesis occurs in the liver.

Cattle liver A red-brown in color, dense consistency, has a flattened convex-concave shape, located in the hypochondrium. The convex side adjacent to the diaphragm is called diaphragmatic, concave, adjacent to the stomach

Rice. 84. Liver:
A- cattle; B- horses; IN- pigs

and intestines - visceral. Dorsally it is distinguished blunt, ventral - sharp edge. Depression of the esophagus is noted at the blunt edge 13 and caudal vena cava 14 . Located on the visceral side of the liver gallbladder 8. On the ventral edge on the visceral side there is a shallow notch in which the round ligament 11(deserted umbilical vein). To the left of it is located left lobe 12, on right - right 7. On the right lobe there is a renal depression 75, square fraction 9- below, between the round ligament and the gallbladder, and above caudate lobe 3 with caudate process 4. The boundary between them is a depression - gate of the liver. Here are included portal vein 2, bringing blood from the digestive organs and spleen, and hepatic artery 1, nerves, lymphatic vessels and hepatic duct 10. The last one in the gate area connects to cystic duct 6 gallbladder, forming bile duct 5, which goes to the duodenum. The hepatic veins drain into the caudal vena cava at the site of its depression. The liver is innervated by the vagus nerve and the nerves of the celiac plexus. Liver vessels: hepatic artery, portal vein, hepatic veins.

At the horse B the left lobe is divided into left lateral 12a And medial 12b shares. The caudate process is adjacent to the right lobe 7 . There is no gallbladder. The hepatic duct leads to the duodenum 10 . The square lobe on the right is separated by a notch.

The pig's liver is yellow-brown in color. The right and left lobes are separated by deep notches into right lateral 7a And medial 76 And left lateral 12a And medial 126. Square fraction 9 small, triangle shaped.

Preparation 61. PIG LIVER (hematoxylin-eosin staining).

The liver (Fig. 85) is a compact organ, consisting of parenchyma of epithelial origin and connective tissue stroma, covered with a serous membrane. The liver stroma consists of a capsule, a large-loop network of connective tissue interlobular layers and a fine-loop network of intralobular reticular fibers.

The liver parenchyma is separated by layers of interlobular connective tissue 1 into multifaceted liver lobules 2 . In pigs, the lobulation of the liver is more clearly expressed, in ruminants and horses it is less noticeable. A gap is visible in the center of the lobule - central vein lobules 3. Strands of liver cells extend radially from it - liver plates(beams) 4 . There are noticeable gaps between them - hepatic capillaries 5.

Rice. 85. Histological structure of the pig liver:
A- small and B- large (liver plate) increase; IN- submicroscopic
hepatocyte structure

Bile glands pass through the interlobular connective tissue excretory ducts 7, arteries 6 And veins 8. They lie close to each other, forming triad.

Place the drug under high magnification B. Examine the liver plate 4 . Liver cells - hepatocytes 9 come into close contact with capillaries 5 . The capillaries of the hepatic lobes are sinusoidal, with a wide lumen, which contributes to the slow flow of blood in the liver. Their wall is formed by endothelium, among the cells of which are star-shaped(Kupffer) cells 10, capable of turning into macrophages and performing phagocytosis. They perform the protective function of the liver. The preparation shows the elongated dark-colored nuclei of these cells.

A feature of the liver epithelium is the absence of a basement membrane. Hepatocytes 9 polygonal in shape, with a large rounded nucleus, in which clumps of chromatin and one or two nucleoli are clearly visible. There are binucleate cells formed as a result of endomitosis.

Electron microscopy IN showed that in hepatocytes it is highly developed endoplasmic reticulum 12, ribosomes, mitochondria 13, a lot of lysosomes 14. Lamellar complex 18 During the period of active synthesis of substances in the cell, it reaches such a development that it becomes noticeable in a light microscope in the form of granularity. Cytoplasmic membrane 17 on the side facing the capillary 5 , It has microvilli 11. Fat inclusions 16 And glycogen 19 at certain moments they can occupy more than 50-60% of the cell volume. Bile, synthesized in hepatocytes from the breakdown products of red blood cells, passes from the cells into bile capillaries 15- extremely small tubules formed by depressions of the cytolemma of adjacent hepatocytes. Only at the borders of the lobule do the bile canaliculi acquire their own epithelial wall, uniting into interlobular bile ducts, which, in turn, form the hepatic duct.

The internal structure of the liver of an adult is subject to the architectonics of the circulatory and bile ducts. The main structural unit of the liver is the hepatic lobule. The cells in it form hepatic beams located along the radii (color. Fig. 1 and 2). Between the beams, sinusoids stretch to the center of the lobule, where the central vein is located. At the periphery of the lobule, the initial bile ducts (interlobular) are formed from bile intercellular capillaries. Enlarged and merging, they form the hepatic duct at the gate of the liver, through which bile leaves the liver. According to Elias (N. Elias, 1949), the hepatic lobule is built from a system of hepatic plates, converging towards the center of the lobule and consisting of one row of cells. Between the plates there are lacunae that form a labyrinth (Fig. 5).

Rice. 1-3. Schemes of the structure of the hepatic lobule (Fig. 3 according to Child): 1-ductuli biliferi; 2 - bile capillaries; 3 - v. centralis; 4 - v. sublobularis; 5 - ductus interlobularis; b -a. interlobularis; 7 -v. interlobularis; 8 - interlobular lymphatic capillaries; 9 - pernvascular nerve plexus; 10 - inflow of interlobular veins.

The lobules form the regions and segments of the liver associated with the branches of the portal vein and hepatic arteries. There are anterior and posterior segments in the substance of the right lobe of the liver, a medial segment occupying the territory of the caudate and quadrate lobes, and a lateral segment corresponding to the left lobe. Each of the main segments is divided into two.

The liver is built of glandular epithelial tissue. The liver cells are separated by bile capillaries (Fig. 6).

Rice. 5. Microscopic structure of the liver lobule (according to Elias); on the right - the portal space for the adductor vein (1), limited by the lamina limitans; a hole (2) for the afferent venule leading to the labyrinth is visible; on the left is a labyrinth of lobules (3), the lacunae of which are limited by the liver plates (laminae hepaticae); the lacunae converge towards the central space (for the central vein).

Rice. 6. Intralobular bile precapillary (1), draining bile from intralobular bile capillaries (2) (according to Elias).

Rice. 7. Lattice (argyrophilic) fibers inside the hepatic lobule (Foot silver impregnation).

The rows of liver cells (beams) are separated from the sinusoids by the perivascular spaces of Disse, into the lumen of which microvilli, the processes of the liver cells, face. Another cellular element of the liver is stellate Kupffer cells; these are reticular cells that act as the endothelium of intralobular sinusoids.

Layers of fibrous tissue between the liver lobules and paravasal connective tissue tracts make up the liver stroma. There are many collagen fibers here, while the stroma of the lobule contains mainly argyrophilic reticulin fibers (Fig. 7).

Cytochemistry and ultrastructure of liver cells. The liver cell - hepatocyte - has a polygonal shape and size from 12 to 40 microns in diameter, depending on the functional state. The hepatocyte has sinusoidal and biliary poles. Through the first, various substances are absorbed from the blood; through the second, bile and other substances are secreted into the lumens of the intercellular bile canaliculi. The absorbent and secretory surfaces of the hepatocyte are equipped with a huge number of ultramicroscopic outgrowths - microvilli, which increase these surfaces.

The hepatocyte is bounded by a double-circuit protein-lipid plasma membrane, which has high enzymatic activity - phosphatase at the biliary pole and nucleoside phosphatase at the sinusoidal pole. The plasma membrane of the hepatocyte also contains the enzyme translocase, which catalyzes the active transport of ions and molecules into and out of the cell. The cytoplasm of the hepatocyte is represented by a fine-grained matrix with low electron density and a system of membranes that are integral with the plasma and nuclear membranes. The latter is also double-circuited, consists of proteins and lipids and surrounds a spherical nucleus with 1-2 nucleoli. The nuclear membrane has pores with a diameter of 300-500 A. Some hepatocytes (there are more of them with age) have two nuclei. Binucleate cells are usually polyploid. Mitoses are rare.

The organelles of the hepatocyte include the endoplasmic reticulum (granular and agranular), mitochondria and the Golgi apparatus (complex). The granular endoplasmic reticulum (ergastoplasm) is built from paired parallel lipoprotein membranes delimiting ultramicroscopic tubules. On the outer surface of these membranes there are ribosomes - ribonucleoprotein granules with a diameter of 100-150 A. The agranular endoplasmic reticulum is built in the same way, but does not have ribosomes.

Mitochondria, numbering 2000-2500, are found in the form of threads, rods and grains of 0.5-1.5 microns in size and are located near the nucleus and along the periphery of the cell. Hepatocyte mitochondria contain a huge amount of enzymes and are the energy centers of the cell. Ultramicroscopically, mitochondria are complex lipoprotein membrane structures that carry out enzymatic transformations of tricarboxylic acids, coupling the flow of electrons with the synthesis of ATP, transfer of active ions into the internal spaces of mitochondria, as well as the synthesis of phospholipids and long-chain fatty acids.

The Golgi apparatus is represented by a network of crossbars of different thicknesses, which are located in different phases of the secretory cycle of the hepatocyte near the nucleus or near the bile canaliculi. Ultramicroscopically, it consists of agranular lipoprotein membranes that form tubes, vesicles, sacs and slits. The Golgi apparatus is rich in nucleoside phosphatases and other enzymes.

Lysosomes - peribiliary bodies - vesicles with a diameter of 0.4 µm or less, bounded by single-circuit membranes, are located near the lumens of the bile canaliculi. They contain hydrolases and are especially rich in acid phosphatase. Non-permanent inclusions (glycogen, fat, pigments, vitamins) vary in composition and quantity. Endogenous pigments are hemosiderin, lipofuscin, bilirubin. Exogenous pigments can be present in the cytoplasm of hepatocytes in the form of salts of various metals.

Liver- the largest human gland - its mass is about 1.5 kg. It performs numerous functions and is a vital organ. The metabolic functions of the liver are extremely important for maintaining the vitality of the body, and therefore it is called the biochemical laboratory of the body. The liver produces bile, which is necessary for the absorption of fats and stimulation of intestinal motility. About 1 liter of bile is secreted per day.

Liver is an organ that acts as a blood depot. Up to 20% of the total blood mass can be deposited in it. During embryogenesis, the liver performs a hematopoietic function.
Liver development. The liver primordium arises at the end of the 3rd week of embryogenesis from the endodermal lining of the ventral wall of the midgut. The protrusion of this wall grows, forming epithelial cords in the mesenchyme of the mesentery. Later, the cords are divided into cranial and caudal sections, from which the liver and gall bladder with ducts are respectively formed.

In histogenesis heterochronic divergent differentiation of hepatic epithelial cells (hepatocytes) and bile duct epithelial cells (cholangiocytes) occurs. Starting from the second half of embryogenesis, structural and functional units - hepatic lobules - are formed in the liver. The formation of lobules is the result of complex interactions between the epithelium and intrahepatic connective tissue with developing sinusoidal blood capillaries.

Structure of the liver. In the liver, epithelial parenchyma and connective tissue stroma are distinguished. The structural and functional units of the liver are the hepatic lobules, numbering about 500 thousand. The hepatic lobules have the shape of hexagonal pyramids with a diameter of up to 1.5 mm and a slightly higher height, in the center of which is the central vein. Due to the peculiarities of hemomicrocirculation, hepatocytes in different parts of the lobule find themselves in different oxygen supply conditions, which affects their structure.

Therefore, in a slice central, peripheral and intermediate zones located between them are distinguished. A feature of the blood supply to the hepatic lobule is that the intralobular artery and vein extending from the perilobular artery and vein merge and then the mixed blood moves through the hemocapillaries in a radial direction towards the central vein. Intralobular hemocapillaries run between the hepatic beams (trabeculae). They have a diameter of up to 30 microns and belong to the sinusoidal type of capillaries.

Thus, along the intralobular capillaries mixed blood(venous - from the portal vein system and arterial - from the hepatic artery) flows from the periphery to the center of the lobule. Therefore, hepatocytes in the peripheral zone of the lobule find themselves in more favorable oxygen supply conditions than those in the center of the lobule.

Along the interlobular connective tissue, normally poorly developed, there are blood and lymphatic vessels, as well as excretory bile ducts. As a rule, the interlobular artery, interlobular vein and interlobular excretory duct go together, forming the so-called liver triads. The collecting veins and lymphatic vessels pass at some distance from the triads.

Liver epithelium consists of hepatocytes, which make up 60% of all liver cells. The activity of hepatocytes is associated with the performance of most of the functions characteristic of the liver. At the same time, there is no strict specialization between liver cells and therefore the same hepatocytes produce both exocrine secretion (bile) and, by the type of endocrine secretion, numerous substances entering the bloodstream.

Educational video on the anatomy of the liver, structure and diagram of the hepatic lobule

Table of contents of the topic "Structure of the stomach. Structure of the intestines.":

A human organ, without which our existence is impossible. Like all other body systems, it consists of smaller components. In this organ, such an element is the hepatic lobule. We will analyze it in detail in this article.

What is this - a liver lobule?

The PD is the smallest morphological unit of the hepatic parenchyma. Visually it has a prismatic shape. In its corners you can see the so-called portal or gate channels. They contain five elements:

We will talk more about the structure of the lobule later.

The structure of the structural segment of the liver

The components of the lobule itself, in turn, are hepatocytes, specific polygonal liver cells. They are quite large in size - 15-30 microns. A fifth of them are binucleate, 70% are mononuclear with a tetraploid set, the rest have a 4- or 8-fold diploid chromosome set.

Hepatocytes form hepatic plates bounded by sinusoidal hepatic capillaries. In the hepatic lobule, such plates are one layer of hepatocytes thick. They are necessarily limited to endothelial cells and hepatic Kupffer sinusoid cells.

Considering the structure of the hepatic lobule, we see that the mentioned plates arise from a number of hepatocytes that limit the lobule from the stroma, namely the limiting plates. Having examined the latter on the anatomical atlas, we will notice that they are dotted with a large number of holes. It is through them that the blood capillaries enter the lobule, forming the hepatic sinusoidal capillary network.

The hepatic plates and sinusoidal capillaries converge towards the vector of the central vein passing through the organ.

Blood supply to the lobule: functional circulation

The blood supply to the hepatic lobule and the entire organ is organized as follows.

The circulation is functional (80% of the total share of the passing blood volume). The portal vein divides into interlobar branches. Those, in turn, branch into interlobular ones, passing in the portal canals. The interlobular branches diverge at strict intervals into short perpendicular branches. They are called interlobular (entrance) venules. They cover the entire segment of the hepatic lobule.

Venous capillaries emerge from the interlobular venules and veins onto the surface of the lobule. It is with their help that blood passes through the holes in the limiting plates into the sinusoidal capillaries of the liver. It then circulates between the hepatic plates and collects in the central vein.

From the central vein, blood is transferred to the sublobular vein, from where it enters the collecting vein. In the end it expires

The role of the described functional circulation is as follows:

Delivery of absorbed nutrients from the digestive system, spleen, pancreas to liver segments.
Transformation and accumulation of metabolites.
Neutralization and removal of toxic substances.

Blood supply to the lobule: nutritional circulation

The nutritional circulation of the hepatic lobule accounts for 20% of the total blood volume passing through the segment.

The branches of the interlobular and hepatic arteries diverge into smaller branches - interlobular arteries, whose path also lies through the portal canals. In turn, they are divided into arterial capillaries. The latter supply the portal canals, bile ducts, and stroma of the organ with fresh, oxygenated blood.

The next stage is that the blood collects in a capillary web, which is formed by the entrance venules and interlobular veins. However, a small part of it (mostly from the interlobular arteries) enters the sinusoidal capillaries. This helps increase the oxygen content of the venous blood circulating in the hepatic sinuses.

Gateway channel

The portal canal is a rounded or triangular space that can be seen at the corners of the hepatic lobule. The VC is filled with loose connective tissue in which fibrocytes, fibroblasts, and wandering cells are located.

Through each channel pass:

Bile duct.
Interlobular vein and artery.
Lymphatic vessels.
Nerve fibers.

Let's talk about each of the presented units in detail.

Blood supply to the portal canal

The blood supply to this part of the lobular parenchyma is represented by the interlobular artery and vein.

Capillary vessels extend from the interlobular vein, penetrating into the limiting plate, from where further into the hepatic lobule in the form of sinusoids. The lateral branches of the vein, located perpendicular to it - the entrance venules also turn into capillaries, becoming sinusoidal, with visible red blood cells.

The interlobular artery here is of a muscular type, smaller in diameter than the vein. Capillaries also branch from it, supplying both the connective tissue of the portal canal and its contents. Some arterial branches are formed predominantly into sinusoidal capillaries.

Capillaries from the arteries surround the bile duct, forming the peribiliary choroid plexus.

Arterial and venous capillaries here have a similar structure. Hepatic sinusoids are actually sinusoidal capillaries. They pass between the liver plates so that their endothelium is separated from the plate only by the narrow space of Disse - the perisinusoidal fissure.

In the areas of bifurcations of the vessels of the hepatic sinusoids, specialized macrophages called Cooper cells are located in a chaotic manner. In the wide areas of the fissures of Disse there are ITO cells, fat-containing or perisinusoidal.

Bile duct channel

Bile ducts in liver segments are always located between the bodies of hepatocytes and pass through the middle part of the hepatic plate.

The terminal bile ducts, distinguished by the fact that they are very short, are called Herring's canals. Lined with a small number of flat cells. Herring canals become visible only at the level of the limiting plate.

These terminal bile canals exit into full-fledged bile ducts, which, passing through the portal canal, flow into the interlobular bile duct. In the anatomical atlas they are visible on the dissected hepatic plate as small holes.

Lymphatic and nervous system of the portal canal

The initial lymphocapillaries begin blindly within the portal canal. Then they, having already been separated from the restrictive plate by a narrow gap called Malle’s space, are formed in. It should be noted that there are no interlobular ones among them.

Nerve fibers of the adrenergic type are accompanied by blood vessels, innervating the portal canal itself. Then, moving into the hepatic lobule, an intralobular web is formed inside it. Nerve fibers of the cholinergic type are also included in the lobule.

Functions of the lobule

The functions of the hepatic lobule are the functions of the entire liver, since it is a constituent segment of this large gland. The range of tasks of the organ, as well as its components, is very wide. We will touch on the basic, most important functions for the body:

Protection - activation of liver lymphocytes.
Metabolism of active biological substances, exchange of mineral elements.
Participation in pigment metabolism. It manifests itself in the capture of bilirubin and its excretion along with bile.
Carbohydrate metabolism. Participation in the process involves the formation and subsequent as well as the synthesis and breakdown of glycogen.
Synthesis of bile, triglycerides, phospholipids. All these elements take part in both the digestive process and fat metabolism.
Synthesis of a wide range of proteins necessary for the functioning of the whole organism - coagulation factors, albumins, etc.
The most important one is the cleansing, detoxification function. The liver is the most important organ that cleanses the entire body of toxins. Through the portal vein, harmful, foreign substances and metabolic products enter the liver segments from the gastrointestinal tract. In this organ they are subsequently neutralized and then excreted from the body.

The hepatic lobule is a component of the liver body. The organ has a complex structure. The vessels, bile ducts and nerve endings supplying the segment pass through its portal canals. The lobules are based on special liver cells - hepatocytes, which have their own unique structure. The functions of both the entire liver and its lobules are similar.