Types of Connective Tissue Flashcards
Types of Connective Tissue
Fibroconnective
Cartilage
Bone
Fibroconnective tissue
matrix composed mostly fibers
Aerolar
loose connective tissue packing material holds organs in place
most common CT in all vertebrates
separates muscles: allows for sliding
fibers in extracellular matrix are collagen/elastin
extracellular matrix is not well organized
Reticular
forms an internal skeleton for lymph, bone marrow, fat & spleen
fibers are collagen/elastin
Adipose
highly vascular insulator, shock absorber and energy store
cells account for 90% of tissue mass
Dense Regular
Closely packed parallel collagen fibers
found where tension is exerted in a particular direction
Ex: tendons, ligaments
Dense Irregular
Closely packed non-directionalized collagen
forms “sheets” where tension is exerted in many directions
Ex: dermis of skin, muscle fascia, organ & nerve coverings
Elastic
composed of mostly elastin fibers
Ex: vocal cords, vertebral CT
Cartilage
Avascular and not innervated
composition of cartilage matrix: collagen/elastin
ground substance: chondroitin sulfate & hyaluronic acid
Perichondrium
Perichondrium
surrounding tissue from which nutrients diffuse
limits cartilage thickness
gives rise to chondrocytes
Types of Cartilage
Hyaline
Fibrocartilage
Elastic
Hyaline
tough & flexible - shock absorber
covers ends of long bones
forms the skeleton of trachea and bronchi
Fibrocartilage
Less firm than hyaline
similar in structure to dense regular tissue
transitional tissue between tendon and articular hyaline cartilage
component of joint capsules and spongy knee menisci
Elastic
contains more elastin fibers than other types of cartilage
forms ear pinna & epiglottis
Bone
Matrix mostly calcium and phosphate
65% of bone weight is calcium hydroxyapatite
contains tropocollagen subunits giving bone elasticity and fracture resistance
highly vascularized and well innervated
contains lymph channels
Calcium hydroxyapatite
calcium phosphate, calcium hydroxide, callium carbonate
Bone functions in mineral storage and cell production
regulation of calcium metabolism - bone remodeling
dec. blood Ca -> inc PTH -> inc osteoclast act.
inc blood Ca-> inc calcitonin -> osteoblast act.
Red bone Marrow
contains hematopoietic tissue
produces blood cells
Influences on Bone Growth
levels of calcium, phosphorous, vitamin D, HGH, estrogen, testosterone
Bone histology & growth plates
SLIDE 30 & 32
Ischemia
widening (breaking) of a distal radial epiphyseal plate
necrotic changes take place and growth may be asymmetrical.
possible premature closing of physis
Pagets Disease
Enlarged, deformed bones
high bone resorption & deposition which leads to thick, soft bones & bone pain. Inc. Fractures/arthritis
Symptoms of Pagets
bending/bowing of weight bearing bones affects 1% of adults (usually over 40) pain, pinched nerves, numbness effected bones: spine, femur, skull, clavicle, humerus treated with bisphosphonate drugs
Osteoporosis
dec. bone density which leads to fracture predisposition
Osteopenia
bone loss but not as severe as osteoporosis
high bone resorption in presence of normal bone metabolism
dec. cortical(more) & trabecular bone density
Osteoporosis causes
prolonged treatment with corticosteroids
anorexia nervosa
inadequate diet, especially during pregnancy
Amenorrhea - inc. estrogen metabolism disturbances - bone loss
Osteoporosis treatment
estrogen replacement for postmenopausal women EVISTA Calcium supplementation vitamin D supplementation Biphosphonate Drugs weight bearing exercise
Osteomyelitis
Bone Inflammation & destruction
caused by bacteria and fungi spreading
symptoms: fever, localized warmth/swelling, pain
treated with antibiotics
Osteoarthritis
Degenerative changes in cartilage and bone
loss in articular cartilage in hands, hips, knees
destruction of hyaline cartilage – joint stiffness
may result in formation of osteophytes (bone spurs) or nodes
Osteoarthritis cases
heredity, infection, endocrine disorders, overuse, fracture or ligament injury
Osteoarthritis treatments
Exercise - helps maintain health and reduces pain
weight loss
NSAIDS & COX2 inhibitors for pain
injections of HYALURONIN or others for lubricants
corticosteroids injections for inflammation
joint replacement
Rheumatoid Arthritis (RA)
autoimmune inflammatory disease
may be related to genetic factors, environmental triggering an autoimmune response, infectious agents
mostly women 25-55
60% of RA patients can’t work after 10 years
life span reduced 5-10 years
Symptoms of rheumatoid arthritis
rheumatoid factor + globulins = immune complexes
immune complexes activate the compliment system causing inflammation
fibrin deposits and necrosis are present in joint
RA may also affect
Heart - endocarditis, pericarditis, CHF, valvular fibrosis, MI
Lungs - fibrosis
Kidneys - amyloidosis (deposition of insoluble proteins in kidney tissue)
GI tract - anemia resulting from constant NSAID use causing bleeding