The common hepatic duct is situated ventrally and to the right of the portal vein (v. portae). This ligament originates from the peritoneum on the convex surface of the liver and runs toward the coronary ligament, which inserts around the exit of the caudal vena cava. The dye particles of selected tracer material must be at least 10 nm diameter because smaller molecules are preferentially reabsorbed by blood vessels. Laboratory rats have anatomical structures of the organs similar to those of humans; therefore, they are the most suitable for anatomical, physiological, and biochemical research on the digestive system. Variations in confluence of extrahepatic part of portal vein in laboratory rat. External genitalia. The liver of the rat is a multilobulated organ. The rat liver is the most cranial structure on the right side of the abdominal cavity, in the intrathoracic portion, coming in intimate contact with the diaphragm. How many lobes does the liver have? Knowledge of anatomical variations is quite important for experimental investigation and surgical practice. On embryonic day 15, the venous duct, post-hepatic caudal vena cava, and portal vein appear in transverse section and the liver lobes are demarcated in coronal section. The extrahepatic part of the portal vein is located on the posterior and lateral to the hepatic artery and common hepatic duct. This information is useful for the planning of experimental surgery and for cooperation with other investigation methods to fight human liver diseases. In rats there are no identified variations in vessel origins, but we described much variability of the liver vasculature. FOIA Our results indicate many variations in confluence of v. portae. Right medial lobe (lobus hepatis dexter medialis), 5. The https:// ensures that you are connecting to the You will notice that rats do not have a gallbladder. The laboratory rat is currently one of the most popular experimental models for research because it is easy to handle and inexpensive. The hepatic lobule is a building block of the liver tissue, consisting of a portal triad, hepatocytes arranged in linear cords between a capillary network, and a central vein.. Lobules are different from the lobes of liver: they are the smaller . Specializes in Pediatric Urology. Pigs have a similar division of the celiac trunk [29]. In the course of the jejunal veins (vv. Examine the hind legs. Welch CW. Both are made up of 8 segments that consist of 1,000 lobules (small lobes). Nejedl K. Cvn soustava. This artery supplies both processes of the caudate lobe, and the caudate and papillary process (processus caudatus et papillaris). The hepatic artery continues at the posterior surface of the portal vein (v. portae). Dorsal side color ___________ Ventral side color ____________ 2. The venous system is more important, along with the portal venous circulation, which is formed by the portal vein (v. portae) and its tributaries. The Arteria coeliaca is the first visceral, unpaired branch, which leaves the ventral wall of the abdominal aorta, just below the diaphragm pillars. Notch for round ligament (incisura ligamenti teretis). Preventricular part of the papillary process (pars preventricularis processus papillaris), 6b. Right medial lobe (r. dexter medialis), 15. Zanchet DJ, Montero EFZ. The liver has a typical dual blood supply, which is the common feature of the hepatic vasculature and clearly determines the regulation and distribution of the blood flow. Right branch of the portal vein (r. dexter), 11. In the longitudinal section, the gall bladder will be in anatomical conjunction with the liver lobes, whereas in the transverse section, the slice of the gall bladder is prone to lose its connection to the liver tissue. A 32-year-old female asked: The rat livers had four lobes (left, middle, right, and caudate). . The caudate lobe (posterior hepatic segment I) is situated upon the posterosuperior surface of the liver on the right lobe of the liver, opposite the tenth and eleventh thoracic vertebrae. Gross anatomical studies on the portal vein, hepatic artery and bile duct in the liver of the pig. While the rat liver is a multilobulated organ, it has about the same surfaces as lobes positioned flat against each other. There are 1016 (10 in 12%, 11 in 25%, 13 in 12%, 15 in 38%, and 16 in 12%) in the jejunal trunks. Up to that point the gas exchange of breathing occurs by way of smooth-walled channels and saccules. The diaphragmatic (Figure 1) convex surface (facies diaphragmatica) is in contact with the diaphragm and right abdominal wall. This gastroduodenal artery is divided into the cranial pancreaticoduodenal artery (a. pancreaticoduodenalis cranialis) of the pancreas and duodenum, and the second branch of the gastroduodenal artery is the right gastroepiploic artery (a. gastroepiploica dextra). Blood by-products are filtered out by the kidneys, and leave the body in the form of urine. The knowledge of the anatomical variability and an understanding of rat liver embryology would help to avoid critical complications when performing experimental surgery on this organ. The abdominal cavity was opened by midlaparotomy through the abdominal wall in the midline (linea alba) from the caudal end of the sternum (processus xiphoideus) to the pubic bone (pecten ossis pubis). The lateral, greater lobes of the liver are joined to the others parts only by means of interstitial tissue and vessels. The vascular system in liver diseases: Its role in ascites formation. Blau JN, Gaugas JM. In: Nickel R, Schummer A, Seiferle E, editors. The lymph travels through the falciform ligament of the liver. Click here for more details concerning guidelines 1, 2a, 3) Transverse, 2b) longitudinal-vertical. The liver is generally the largest group of cells composing homogeneous antigenic matter that can be easily transplanted in the mammal body [12]. 4 How does the anatomy of a female rat differ from that of a human? 111, Lyon, pp 271279. Some of the more well-known functions include the following: Production of bile, which helps carry away waste and break down fats in the small intestine during digestion, Production of certain proteins for blood plasma, Production of cholesterol and special proteins to help carry fats through the body, Conversion of excess glucose into glycogen for storage (glycogen can later be converted back to glucose for energy) and to balance and make glucose as needed, Regulation of blood levels of amino acids, which form the building blocks of proteins, Processing of hemoglobin for use of its iron content (the liver stores iron), Conversion of poisonous ammonia to urea (urea is an end product of protein metabolism and is excreted in the urine), Clearing the blood of drugs and other poisonous substances, Resisting infections by making immune factors and removing bacteria from the bloodstream. The maceration of the soft tissues was carried out in 24% solution of KOH (Mikrochem, Slovakia) at 6070 C. There is a very close relationship between the 2 vascular systems of the rat liver: hepatic arterial and venous blood supply. falciforme) is a thin peritoneal fold attached to the convex surface of the diaphragm and the caudal surface of the right abdominal muscles. Prior to the outset of the drying process, the corroded specimens were submersed in water and dried at room temperature. Quadrate lobe (lobus quadrates), 6. Images were taken with a digital camera adapted to the microscope. The weight of the liver in carnivores is 34% of body weight, about 2% in omnivores, and about 11.5% in herbivores [38]. Celiac artery compression syndromes. The rat liver is the object of extensive investigation because recent evidence demonstrates their involvement in different processes (e.g., secretion, proliferation, absorption, and neoangiogenesis) significant for its pathophysiology. The alveoli and alveolar ducts do not develop until the 7th day following birth. Jejunal veins are formed by the fusion of the venous arcades, which drain the blood from the wall of the jejunum. Morphometric and physiological parameters and associated structures of rat liver. [40]. Osman et al. heart, lungs, and diaphragm What is the main functions of the vibrisse? The porta of the liver (porta hepatis) is located on the visceral surface. Blood travels through the liver. The portal vein was formed by 4 tributaries in 23%, by 3 branches in 64%, and by 2 tributaries in 13%. The liver holds about one pint (13%) of the body's blood supply at any given moment. 5. The right hepatic duct is formed by the confluence of the duct from the caudate and right lobe. coronarium dextrum et sinistrum). The median lobe was divided into the right and left parts. The right lobe is functionally separated from the left lobe by the middle hepatic vein. -connects right lateral surface to the diaphragm. These ligaments attach the liver to the diaphragm on a line from the right triangular ligament of liver (lig. uterus what do female humans have in their reproductive system? Many authors reported that there is not cystic bud in rats [13,16,17]. Experimental transplantations of the liver have been studied in many mammals, especially in dogs [6,7], swine [8,9], in laboratory animals [10], and in other mammals [11]. lobi quadrati). The lymph nodes and the drainage area were evaluated macroscopically and by using an operating microscope (model M 320, Leica). External genitalia. Figure 1. Pujahari AK. Along its course, it ramifies into 4 or 6 collateral branches for the residual for the right lateral lobe of liver. lobi caudati) are tributaries of the r. dorsalis lobi lateralis dextri or v. portae (Figure 5). On embryonic day 19, there is a marked increase in the number and size of hepatocytes in the rat liver tissue. When we opened the abdominal cavity through the linea alba, the rat liver had generally 2 surfaces: diaphragmatic and visceral. [7] Besides, the caudate lobe also derives its supply from the right and left branches of the portal vein. 3 How many livers do mice have? 1. We mixed the injection media in stoichiometric rates. In some cases, another small branch, which enters directly to the ventral side of the portal vein, drains blood from the ventral part of the right lateral lobe. Biologie a soustavn anatomie laboratornch zvat. Under anesthesia and after heparin administration (50 000 IU/kg; Heparin Liva, Zentiva, Czech Republic), rats were exsanguinated from the jugular vein before they could regain consciousness. The lymph of the liver is drained in 2 ways. Table 3 showed our findings in tributaries of extrahepatic portal venous system. This surface includes part of the left lateral and medial lobes of the liver. Right lateral branch (r. dexter lateralis), 12a. Larger liver consist of more rather than larger lobules. The division of the hepatic artery outside the liver observed in the present was also reported by many authors [16,39,40,50]. Among laboratory animals, rat morphology is very similar to humans. [5], The lobes of the liver are further divided into eight liver segments in the Couinaud system. Between the left, medial lobe and quadrate lobe is the deep notch for the round ligament (incisura ligamenti teretis), which contains the round ligament (lig. Functional Unit At the cellular level the liver has a basic functional unit call the acinus. Haller A. Icones anatomicae in quibus praecipae partes corporis humani delineate proponuntur et arteriarum potissimum histiria continetur. After perfusion, the liver was removed and cleaned of connective tissue. Left branch of the portal vein (r. sinister), 12. (A) Normal drainage of bile in rat liver, (B, C) Variations of bile drainage from quadrate lobe, (DF) Variations of bile drainage from caudate lobe. Shannan Muskopf Granite City School District via Biology Corner External Anatomy 1. The laboratory rat (. Many authors have described 4 main branches of the portal vein in pigs [51,52]. Left lateral branch (r. sinister lateralis), 3. 11. Corresponding Author: Katarna Vdoviakov, e-mail: Received 2016 Apr 18; Accepted 2016 Apr 24. The sinusoids of the blood are thin irregular structures between the cords of the liver cells. There is not communication between the portal and venous system of the rat liver, but each of the 6 sectors receives a portal branch and has its own venous tributary [26]. 16 How many digits are present on, Through the umbilical cord and out with the mother's waste How does a fetus get rid of it, the liver To what organ does the umbilic, 5 lobes How many lobes does the liver falciforme), 9. The anatomy of the pig is very different from other domestic animals. It derives its arterial supply from the caudate arteries, which arise from the right, left, and middle hepatic arteries that are connected to each other. "Cantlie's line | Radiology Reference Article", "Morphology and morphometry of the caudate lobe of the liver in two populations", "A practical study of the hepatic vascular system anatomy of the caudate lobe", https://en.wikipedia.org/w/index.php?title=Lobes_of_liver&oldid=1164214886, Wikipedia articles incorporating text from the 20th edition of Gray's Anatomy (1918), Creative Commons Attribution-ShareAlike License 4.0, This page was last edited on 8 July 2023, at 10:28. Retroventricular part of the papillary process (pars retroventricularis processus papillaris), 7. Intestinal branch of the hepatic artery. The falciform ligament of the liver (lig. [10] The perfusion pressure was approximately 200250 mmHg (2.63.25 m H2O). How many lobes (sections) does the liver have? Vessels were perfused with 0.9% isotonic saline physiological solution at a low flow rate (about 10 ml/min) for 30 s through the left cardiac ventricle. Moawad RS, Hegab AS, Barey MAE, Sabry RM. 7. In some cases, 2 or 3 lobar arteries follow a single lobar branch of the portal vein. A very well-defined border divides the convex from the concave surface. An impairment of its function causes lymphedema and ascites [57]. The right lung consists of three lobes: the superior, middle, and inferior lobes. Abdominal aorta (aorta abdominalis), 2. Right lateral branch (r. dexter lateralis), 5. To monitor the lymphatic progress of the dye, we used ink of various colors (black, blue, and green). The reason is that rodents have a lobated liver, of which individual lobes can be easily ligated and removed, whereas humans have a non-lobated liver. There are 4 such borders in the rat liver: right, left, ventral, and dorsal. 2. [2] A line can be imagined running from the left of the vena cava and all the way forward to divide the liver and gallbladder into two halves. A portion of the venous system was opened to ensure a good distribution of the perfusion medium; the right auricular appendage served this purpose. It is a multifunctional accessory organ of the gastrointestinal tract and performs several essential functions such as detoxification, protein synthesis, bile production and nutrient storage to name only a few. Nickel R, Schummer A, Seiferle E. A. hepatica. In: Turusov VS, Mohr U (eds) Pathology of tumours in laboratory animals. Majorov E, Mrz M, Drahovsk P. Syndrm krtkeho reva. Saline was perfused continually until casting, to remove the fixative and increase the permeability of the resin. For identification purposes, standardized shaping of one of the larger lobes can be performed. The liver performs many other functions: production of bile, proteins for blood, cholesterol and special proteins to help carry fats, store and release glucose, transformation of harmful ammonia to urea, and creating immune factors. The groove for the caudal vena cava is termed the sulcus venae cavae. Many authors have used different nomenclature for the lymphatic system [6265]. The results of research by Martins et al. 3)Right triangular ligament. [49] showed that in most of cases, the celiac trunk in rats is divided into the splenic artery and the common hepatic artery, while the left gastric artery arises as a first branch and originates between aorta, all over the celiac trunk, up to a bifurcation. Viewed from the underside the visceral surface the other two smaller lobes, the caudate lobe and the quadrate lobe, are also visible. Madrahimov N, Dirsch O, Broelsch C, Dahmen U. Clearance of bilirubin, also from red blood cells. A study by Martins et al. Takasaki S, Hano H. Three-dimensional observations of the human hepatic artery (arterial system in the liver). From this parietal view, seven segments can be seen, because the eighth segment is only visible in the visceral view. Cotton-tipped sticks, forceps, and a stereotactic microscopic (Leica M 320) were used for anatomical dissection. In the third group of rats under sodium pentobarbital anesthesia (50 mg/kg, Thiopental Valeant, Valeant Czech Pharma, Czech Republic), we opened the abdominal cavity via the linea alba. uterine horn what do female rats have in their reproductive system? Falciform ligament of liver (lig. Sarsilmaz M, Gumusalan Y, Celk HH, et al. The initial hematopoiesis in mammals takes place in the fetal liver [14]. The greater omentum (omentum majus) continues to the greater curvature of the stomach as the gastrosplenic ligament (lig. 2)Coronary ligament. The primitive epithelial cells of the foregut form the hepatic bud, which is divided into a smaller caudal part (pars cystica) and a larger cephalic part (pars hepatica). Colour Atlas of Anatomy of Small Laboratory Animals. 1 thank. Forty Wistar laboratory rats (Rattus norvegicus f. domestica) of both sexes, aged 1 year and weighing approximately 350520 g in standard breeding condition were used. The extrahepatic bile ducts are more superficial and the common hepatic duct is longer in rats than in the human common bile duct. Branch for papillary process, 6b. The nomenclature and morphological characteristics of the rat liver vary among authors. In: Turusov VS, Mohr U (eds) Pathology of tumours in laboratory animals. Medical Science Monitor : International Medical Journal of Experimental and Clinical Research. The right medial branch is represented by 2 or more vessels supplying the right medial lobe (lobus hepatis dexter medialis), dorsal part of the quadrate lobe (lobus quadratus), and part of the left medial lobe (lobus hepatis sinister medialis). lobi mediales sinistri) are tributaries of the left branch of the portal vein. Osman FA, Wally YR, El Nady FA, Rezk HM. The caudal part gives rise to the gallbladder and cystic duct and the cephalic part gives rise to parts of the parenchyma of the liver, intrahepatic ducts, and both (right and left) hepatic ducts. triangulare dextrum) along the right side of the caudal vena cava and around the ventral margin of the caval opening (foramen venae cavae) to the left triangular ligament (lig. Davies B, Morris T. Physiological parameters in laboratory animals and humans. The liver of ruminants has no fissures. The corrosion casts were prepared with Duracryl Dental resin (Spofa-Dental, Czech Republic). Duct of papillary process. 4 duodenum 1st part of the small intestine mesentery skin inside the rat What organs/structures are found in the thoracic cavity? The presence or absence of a gallbladder does not convey a selective advantage. Tilney NL. The liver veins were evaluated macroscopically and by using an operating microscope (model M 320, Leica). The ink (another color) was applied under the liver capsule on diaphragmatic surface was found in the parathymic nodes. Ventral branch of the right lateral lobe (r. ventralis lobi lateralis dextri), 13. The application of an anticoagulant is a key requirement for high-quality vascular casting. The arterial limbs continue on the anterior surface of the portal vein, pass behind the common hepatic duct (ductus hepaticus communis), and accompany a parallel course with the branches of the portal vein as they divide into their main lobar division (Figure 4). Tumours of the mouse, 2nd edition. In: Popesko P, Rajtov V, Hork J, editors. In histology (microscopic anatomy), the lobules of liver, or hepatic lobules, are small divisions of the liver defined at the microscopic scale. Lupinacci RM, Paye F, Coelho FF, et al. The circulatory system, the skin and the cutaneous organs of the domestic mammals. As a library, NLM provides access to scientific literature. Elias H, Petty D. Gross anatomy of the blood vessels and ducts within the human liver. The liver of the pig resembles that of the dog, but does not have a papillar process. This artery supplies the stomach, spleen, liver, pancreas, and cranial part of the duodenum, and it branches into the splenic artery (a. lienalis), left gastric artery (a. gastrica sinistra), and hepatic artery (a. hepatica). Forty laboratory rats were dissected to prepare corrosion casts of vascular system specimens (n=20), determine the lymph vessels and lymph nodes (n=10), and for macroscopic anatomical dissection (n=10) of the rat liver. The left, right, and ventral border are very sharp but the dorsal border is oblique. The left branch (r. sinister) of the portal vein has tributaries for the lateral and medial part of the left lobe and for the quadrate lobe. This helps carry away waste products from the liver. Only one large dorsal branch drains blood from the dorsal part of the left medial lobe of the liver. The .gov means its official. Adachi B. Das Arteriensystem der Japaner. Tsuneki K, Ichibara K. Electron microscope study of vertebrate liver innervations. Kongure K, Ishizaki M, Nemoto M, et al. These lymph nodes also receive subcapsular applied dye from the visceral surface of the liver, identified by using dyes of different colors, showing that most of the lymph coming from the liver leads to the thoracic duct (ductus thoracicus).
