Histology Chapter 6 Connective Tissue
what do natriuretic peptides do
(formed by cardiac muscles) can induce ATL and HSL activities
plasma cell life span
2 to 3 weeks
What are adipose Cells
Adipose cells are fully differentiated cells that function in the synthesis, storage, and release of fat.
Specialized connective tissue
Cartilage bone blood
What type of tissue is a tendon composed of?
Dense regular connective tissue
what induces glu uptake and fatty acid oxidation by skeletal muscle cell
Interleukin -6
what is the loose connective tissue of the mucous membrane called
Lamina propria
Leukocytes
Leukocytes exit the bloodstream during inflammation, invasion by foreign elements, and immune responses to perform various functions
Once in the capillaries of adipose tissue VLDL, fatty acids and chylomicrons are exposed to what
Lipoprotein lipase
Connective Tissue proper
Loose ( areolar) connective tissue Dense Types Dense irregular Dense regular Collegen Elastic Reticular Adipose
Collagen fibers can be differentiated from other fibers by staining with
Masson's trichrome stain.
Mast Cells
Mast cells arise from bone marrow stem cells and function in mediating the inflammatory process and immediate hypersensitivity reactions.
Embryonic connective tissues
Mesenchymal connective tissue mucous connective tissue
What does connective tissue develop from?
Mesenchyme
what represents transitional modifications of fibroblast
Myofibroblast
What is released from nerve endings of postganglionic sympathetic neurons in the vicinity of fat cells
Norepinephrine
Obesity Nugget
Obese individuals possess increased insulin resistance believed to be effected by RBP-4, and this adipokine may be partly responsible for the presence of chronic inflammation and fatty liver disease in these individuals.
Pericytes
Pericytes surround endothelial cells of capillaries and small venules and technically reside outside of the connective tissue compartment because they possess their own basal lamina.
Plasma Cells
Plasma cells are derived from B lymphocytes and manufacture antibodies.
What increase insulin resistance
Resistin
Lymphocytes types
T lymphocytes, B lymphocytes, natural killer cells
what interferes with fatty acid oxidation by hepatocytes
TFN-a
What is the primary cause of insulin resistance?
TNF-α
nugget
The cells are the most important components in some connective tissues, whereas fibers are the most important component in other connective tissue types. For example, fibroblasts are the most important cell component of loose connective tissue because these cells manufacture and maintain the fibers and ground substance composing the ECM. In contrast, fibers are the most important component of tendons and ligaments. In still other connective tissues, the ground substance is the most important component because it is where certain specialized connective tissue cells carry out their functions. Thus, all three components are critical to the role of connective tissue function in the body.
What color do elastic fibers stain with Verhoeff Elastic stain?
Verhoeff Elastic stain stains elastic fibers blue/black. Collagen stains pink/red
A peripheral blood smear would be best visualized with .
Wright's stain
Which of the following is not associated with connective tissue? a. Tightly packed cells b. Extracellular fibers c. Tissue fluid d. Ground substance e. None of the above; all of the above are seen with connective tissue
a Connective tissue consists of cells and extracellular fibers in a ground substance and tissue fluid. There is generally abundant extracellular space in connective tissue; the cells are not tightly packed.
What is Leptin?
a protein that is made and released by adipocytes in a diurnal rhythm ( lowest in afternoon and highest in the mid morning.)
Thermogenin
a transmembrane protein located on the inner membrane of mitochondria, permits backflow of protons instead of using them for synthesis of ATP;
what do pericytes contain
actin myosin and tropomyosin are similar to smooth muscle
What does alpha-melanocyte-stimulating hormone do
acts of the appetite control center to suppress appetite
What do adiponectin octadecamers activate
adenosine monophosphate (AMP) -activated protein kinase
what hormones do adipose produce
adipokines
Adipokines can be produced by
adipose cell macrophages that reside in stroma of adipose tissue
What converts triglycerides to diglycerides
adipose triglyceride lipase
Leptin also induces increased levels of what
alpha- melanocyte stimulating hormone
Macrophages
are mononuclear phagocytes.
Leukocytes
are white blood cells that circulate the bloodstream
What type of connective tissue is an undifferentiated tissue found in the embryo? a. Mucous connective tissue b. Mesenchyme c. Loose irregular connective tissue d. Dense irregular connective tissue e. Dense regular connective tissue
b Mesenchyme is embryonic connective tissue. It is an undifferentiated tissue found in the embryo. Mucous connective tissue is a type of embryonic connective tissue; it is a subset of mesenchyme. Wharton's jelly is mucous connective tissue. Loose irregular connective tissue is areolar tissue. Dense irregular connective tissue is seen in the dermis. Dense regular connective tissue comprises tendons and ligaments.
What is Lipoprotein Lipase
breaks down VLDL, fatty acids, and chylomicrons into free fatty acids and glycerol
What are Sacromas
cancers that arise from cells of connective tissue
Hypercellular obesity
causes overabundance of adipocytes
connective tissue is made of
cells and extracellular matrix ( ground substance and fibers)
preadipocytes,
cells that, under the influence of a series of activating factors, differentiate into adipocytes.
When triglycerides are surrounded by proteins they form
chylomicrons
What is found in the ground substance
collagen reticular elastic fibers
Dense irregular connective tissue
collagen fiber bundles are arranged randomly
What is Dense irregular connective tissue made up of
collagen fibers Fibroblast located between collagen bundles
Dense regular connective tissue is divided into what
collagenous and elastic
mature connective tissue is
connective tissue proper/ specialized connective tissue
Histiocytes are macrophages seen in
connective tissue.
mesoderm gives rise to
connective tissues and their cells, including those of bone, cartilage, tendons, capsules, blood and hemopoietic cells, and lymphoid cells
Dense Connective Tissue
contains most of the same components found in loose connective tissue has many more fibers and fewer cells
What is Dense regular collegenous connective tissue made of
couse collagen bundles oriented into parallel cylinders or sheets that resist tensile forces
Which connective tissue cell is derived from B lymphocytes? a. Fibroblast b. Myofibroblast c. Histiocyte d. Plasma cell e. Mast cell
d
Fixed macrophages are given a unique name,
depending on the tissue that they are located in.
Where is Dense irregular tissue found
dermis of the skin sheaths of nerves capsules of spleen testes ovary kidney lympy nodes
Which of the following is a component of the ground substance? a. Hyaluronic acid b. Proteoglycans c. Glycosaminoglycans d. Chondroitin sulfate e. All of the above
e
Dense regular elastic connective tissue
elastic fiber with only few collagen fibers fibroblast
Where is mesenchymal connective tissue present
embryo and made of mesenchymal cells
What is released from the suprarenal medulla during excerised
epinephrine and norepinephrine
Adipose cells can convert glucose and amino acids into _____ when stimulated by _______
fatty acids; insulin
Dense regular connective tissue
fiber bundles of the tissue are arranged in parallel or organized fashion
What cells are housed in the ECM of the loose connective tissue
fibroblast adipose cell macrophages mast cells undifferentiated cells
what cells repair?
fibroblast that make fibrous connective tissue
Loose ( Areolar) connective tissue
fill in the spaces of the body just deep to the skin lies below that mesothelial lining of the internal body cavity
two types of cell groups in connective tissue
fixed and trainsient cells
Fusiform precursor cells
found near the end of fetal life differentiate in many areas of the connective tissues within the fetus and begin to accumulate lipids that coalesce into the single droplet in each cell, thus forming the unilocular fat cells found in adults
Reticular fibers form what
framework of liver sinusoid adipose tissue bone marrow lymph nodes spleen smooth muscle islets of langerhans
Transient cells
free or wandering cells originate mainly in bone marrow and circulate in the blood stream plasma cells lymphocytes Neutrophils Eosinophils basophils monocytes macrophages
Another name for secondary fat formation is
fusiform precursor cells
what is a edema
gross swelling
What is loose connective tissue characterized by abundant
ground substance and extra cellar fluid
White adipose tissue
has blood vessels that form capillary networks in tissue
What do mast cells contain
heparin histamine ( chondroitin sulfates) neutral proteases ary sulfatase eosinophil Chemotactic factor neutrophil chemotactic factor
Kupffer cells are the
hepatic macrophages.
What completes the hydrolysis of trglyceride to diglycerides forming glycerol and fatty acid
hormone sensitive lipase (HSL)
Plasma cells produce and secrete antibodies that are responsible for
humorally mediated immunity
what is the matrix of mucous tissue made of
hyaluronic acid type 1 and type 3 collagen fibers fibroblast
When does primary fat formation occur
in early fetal life
Where id Unilocular fat present
in subcutaneous layers in the body
Where are Myofibroblast abundant
in wound areas healing where they function in wound contraction
What do adiponectin Octadecamers do
increase insulin sensitivity of skeletal muscles cells (causes these cells to internalize glucose and oxidize fatty acids)
What does the plasma membrane of unilocular adipose cell contain receptors for
insulin growth hormone norepinephrine glucocorticoids
The plasma concentration of adiponectin is
inversely proportional to the amount of adipose tissue an individual possesses
Adipocytes manufacture and release what
leptin adiponectin retinol binding protein- 4 (RBP-4)
Mediators synthesized by mast cells
leukotrienes prostaglandins thromboxanes Cytokines
Where is very low density lipoprotein synthesized
liver
septa partition fat into
lobules
Mucous tissue
loose amorphous connective tissue has jelly like matrix.
Microglia are the central nervous system
macrophages.
Largest fixed cells of the connective tissue
mast cell
most connective tissue originates from
mesoderm ( the middle germ layer of embryonic tissue0
Myofibroblast
modified fibroblast that demonstrate characteristics similar to those of both fibroblast and smooth muscle cells
fibroblast
most abundant resident cell most abundant derived from undifferentiated mesenchymal cells and synthesize the ECM of connective tissue
what is brown adipose tissue forms by
multilocular fat cells which have small lipid droplets
Mesenchymal cells are what and where do they develop?
multipotenial cells; mesoderm
do adipose cells undergo cell division
no that are fully differentiated
ECM
non living material with ground substance and fibers resist compressive and stretching forces
Leptin resistance is found where
obese individuals
What are mesenchymal cells
oval nucleus exhibiting a fine chromatin network and prominent nucleoli found in embryos
During digestion fats are broken down in the duodenum by
pancreatic lipase into fatty acids and glycerol
what is a histiocyte
phagocyte of connective tissue ( is a macrophage)
defense and protection is carried out by
phagocytic cells immunocompetent cells cells that produce pharmacological substances that control inflammation
Neutrophils
phagocytose and digest bacteria in areas of acute inflammation
Cytokine
platelet-activating factor (PAF), bradykinins, interleukins (IL-4, IL-5, IL-6), and tumor necrosis factor-alpha (TNF-α)
epithelioid precursor cells
preadipocytes that are distributed at certain locations in the developing fetus
Where are lymphocytes present
present only in small numbers in most connective tissue, except at sites of chronic inflammation, where they are abundant.
Retinol- Binding Protein-4
product of adipocytes interferes with the ability of insulin to effect glucose uptake by skeletal muscle cells and to amplify glucose production and release hepatocytes
Interleukin- 6
product of macrophages Increases insulin resistance;
Resistin
product of macrophages responsible for insulin resistance in obese individuals
Tumor Necrosis Factor- alpha
product of macrophages primary cause of insulin resistance, and it also interferes with fatty acid oxidation by hepatocytes.
Adiponectin
protein hormone produced by adipocyte that circulates in blood in various combinations as multimers
fibrocyte
quiescent fibroblast
What does leptin do
reduces appetite by binding to neuropeptide Y, inhibiting this signaling molecule from triggering the appetite control center of the hypothalamus to induce the feeling of hunger.
Basophils
release preformed and newly synthesized pharmacological agents that initiate, maintain, and control the inflammatory process
Chylomicrons
released into the extracellular space at the basolateral membranes of the surface absorptive cells, enter the lacteals of the villus, and are carried by the lymph to the bloodstream.
how do eosinophils combat parasites?
releasing cytotoxins
What does adenosine monophosphate (AMP)-activated protein kinase do
represses glucose release and increases gluconeogenesis by the liver
active fibroblast
reside in close association with collagen bundles, where they lie parallel to the long axis of the fiber
fixed cells
resident population of cells that have developed and remained in place within tissue fibroblast adipose cells pericytes mast cells macrophages
What represses hepatic AMP- Activated protein kinase
resistin this causes the elevation of glucose release by the liver resulting in hyperglycemia and contributing to obesity, chronic inflammation, and type 2 diabetes mellitus
Macrophages release what
resistin TNF-alpha interleukin- 6
Dust cells are alveolar macrophage found in the
respiratory tract.
what is Hypertrophic obesity
results from the accusation and storage of fat in unilocular fat cells
Silver impregnation, such as with a reticular stain, can be used to visualize
reticular fibers
Hematoxylin and eosin stain is the most commonly used tissue stain for
routine histological examination
how do blood vessels and nerves gain access to connective tissue
septa
Eosinophils
simular to neutrophils are attracted to inflammation via leukocyte chemotactic factors
Langerhans cells are macrophages seen in the
skin.
Inactive Fibroblast
smaller and more ovoid and posses an acidophilic cytoplasm . nucleus is smaller and elongated
Lipids are best displayed with a
sudan stain
Bone, cartilage and ligaments holding the bones together and tendons act as
support
Functions of Connective tissue
support medium for exchange of nutrients and waste defense, protection, and repairs storage of fat
What are examples of dense regular collagenous connective tissue
tendon ligament aponeuroses
how do Myofibroblast differ from smooth muscle cells
the external lamina ( basal lamina is absent
The intestinal epithelium absorbs fatty acids and glycerols and reesterifies them in the SER to
triglycerides
What is the main component of reticular fiber
type 3 collagen
Where are fat cells derived from
undifferentiated fibroblast- like mesenchymal cells
Where are pericytes derived from
undifferentiated mesenchymal cells
Adipose tissue types include
unilocular multicocular
White adipose tissue is formed by what
unilocular fat cell that has one large lipid droplet
adipokines
uses macromolecules to degrade the triglyceride depot into fatty acids and glycerol which is then released in to the body
whats another name for mucous tissue
wharton jelly
What tissue is only found in the umbilical cord
wharton jelly/ Mucous tissue
what are the two fat cells
white adipose tissue and brown adipose tissue
Are pericytes multipotent
yes
