DOC

Articular cartilage chondrocyte apoptosis following impact injury in experimental study_6136

By Lori Russell,2014-10-30 10:00
13 views 0
Articular cartilage chondrocyte apoptosis following impact injury in experimental study_6136

    Articular cartilage chondrocyte apoptosis following impact injury in experimental study

     Authors: Shao-kun, Fu-Xing Pei, Di Dong-hua, Zhao Jianzhong

     Abstract Objective] with the TUNEL labeling method and transmission electron

    microscopy to observe the cartilage after impact injury in the evolution of chondrocyte apoptosis. [Method] 56 healthy adult New Zealand white rabbits were randomly divided into high and low energy groups, each of 28 randomly selected side of the hind

    limbs of the experimental group, on the other side of the control group; different weights of the hammer hit the inside of the femur condylar cartilage damage caused by the different. After 4 d, 1,2,4,8,16,32 weeks to collect specimens, each time group 4

    rabbits, carried out TUNEL labeling method and transmission electron microscopy to observe the apoptosis of chondrocytes. [Results] In the control group, specimens from the middle layer and calcified cartilage layer, apoptotic cells. Low-energy group, after

    injury 4 d, 1,2-week specimens, cartilage intermediate layer of the transitional layer and apoptotic cells, the apoptotic rate between the control group had no statistical significance; 4 weeks after the specimen significantly reduced in apoptotic cells,

    apoptosis rate were not statistically significant between groups. High-energy group, 4 d

    after injury cartilage surface and transitional layer of light appears in apoptotic cells, and the injury the longer the greater the percentage of apoptotic cells, apoptosis rate

    were statistically significant between groups . [Conclusion] cartilage high, low-energy

    impact injuries suffered from an early chondrocyte apoptosis, apoptotic rate was higher; but low-energy injury 4 weeks after chondrocyte apoptosis returned to control

    levels; high-energy injury cartilage apoptosis rate increased gradually over time.

     Key words cartilage; cartilage cells; apoptosis; traumatic osteoarthritis

     Recent studies have shown that osteoarthritis and cartilage injury in vitro model,

    can be observed in chondrocyte apoptosis. With the increasing severity of osteoarthritis, cartilage cells, also increases the rate of apoptosis, mechanical damage can also induce chondrocyte apoptosis, which may be cartilage cells to mechanical damage, one of the earliest reactions [1,2] . Articular cartilage in vivo after injury by impact, cartilage cell apoptosis rate in the evolution of a lack of sufficient knowledge of the people. This experiment Newberry, Vrahas model based on the rabbit medial

    femoral condylar cartilage of different models, with the TUNEL labeling method and transmission electron microscopy observation of cartilage injury in the evolution of chondrocyte apoptosis.

     1 Materials and methods

     1.1 Animals and Grouping

     56 healthy adult rabbits, of either sex, weighing 3.0 ~ 3.5 kg, were randomly divided into light and heavy two groups of 28, randomly selected side of the hind limbs of the experimental group, on the other side of the control group. And then randomly divided

    into two after 4 d, 1,2,4,8,16,32 weeks 7 hours groups, each with four animals.

     1.2 The establishment of articular cartilage injury model

     1.2.1 5% chloral hydrate 1.25 ml / kg intraperitoneal injection of anesthesia, supine position to take, hair removal, routine disinfection shop towel.

     1.2.2 medial longitudinal incision length 3 cm, followed by skin incision, subcutaneous tissue, deep fascia, joint capsule will patella eversion, knee flexion 120 ?, so that femoral shaft with the horizontal plane perpendicular to a fixed pelvis with fixed pelvis, thigh, with the thigh fixed to prevent collisions with fixed unstable.

     1.2.3 use the hammer 1.33,0.43 kg, respectively 46,20 cm height of free fall through the guide rod, the resulting energy of 6.3 J (can cause collagen lattice fault) and 0.9 J (not caused by collagen rack fault) [2,3], and through the body caused by collision medial femoral condyle cartilage damage. No control side impact, I step in the same test group. Gentamicin saline flush operation completed joint cavity, layer by layer suture the wound. Anesthesia conscious cage freely. After intramuscular injection of penicillin 200,000 units, 2 times a day qd for 3 d.

     (4) was after 4 d, 1,2,4,8,16,32 weeks to collect samples for TUNEL labeling method

    and transmission electron microscopy to observe the apoptosis of chondrocytes.

     1.3 Morphological observation

     1.3.1 drawn, fixed

     After the expiration of each group to observe, in the same location with a sharp

    double-sided blade Department subchondral bone were cut 0.5 cm × 0.4 cm × 0.2 cm of cartilage, subchondral bone and did not take to avoid the damage due to the process of specimen decalcified cells, causing false positive. Specimens cut two equal parts, one

    were immediately placed in 10% neutral formalin solution at room temperature for a fixed 24h, paraffin-embedded tissue blocks for serial sections, sheet thickness of 51 μm, made of pathology standby. The other one were prepared to do transmission electron

    microscope use.

     1.3.2 TUNEL-end labeling

     Biopsy conventional dewaxing, the gradient of alcohol, after replenishment, sliced dropping antigens proteinase K repair. Dropping 20% fetal calf serum and 3% bovine

    serum albumin closure of non-specific reactions. In the DNA fragment labeled with 0.3% H2O2 blocking endogenous peroxidase, room temperature, 15 min. Slice dropping 20% goat serum, 3% bovine serum albumin and 1% blocking agent, 37 ?, 15

    min, once again closed to non-specific reactions. Slice dropping 1:2 diluted POD 20 μl, home wet box, 37 ?, 30 min to the immune response to expand the signal. Mirror tap water reaction. Hematoxylin. Gradient alcohol dehydration, xylene and

    transparent, gums Fengpian.

     1.3.3 Transmission electron microscopy

     Specimens were placed in 5% glutaraldehyde preservation fluid infiltration protection, double-sided blade with a sharp coronal cut into 1 mm3 pieces will be

    cartilage, immediately put into 4 ? 5% glutaraldehyde solution, fixed 24 h later, 0.1 mol / L dimethyl arsenite buffer (pH7.35) rinse 24 h. 1% osmium tetroxide post-fixed 2

    h, ethanol, progressively dehydrated resin-embedded, ultra-thin slicing machine 70 nm

    transmission electron microscope observation filming.

     1.4 Image Analysis

     Each one TUNEL marker sectioning microscopy camera microscope (magnification 10 × 40), randomly selected four vision to capture the image into the computer, and the analysis system of doing image analysis, using target count, determination of chondrocyte apoptosis rate, obtained after the arithmetic mean apoptosis rate of each slice. Reposted elsewhere in the paper for free download http://

     1.5 Statistical analysis

     With the SPSS 12.0 statistical software package, according to high and low energy group and the corresponding control group were compared to 22, using t test, take 95% confidence interval were observed in all experimental groups and control group

    the rate of chondrocyte apoptosis in the availability and Statistics learning differences.

     2 Results

     Postoperative survival of all experimental animals were drawn to the scheduled time, incision healed well and no infection in 1 case.

     2.1 TUNEL labeling observed rate of chondrocyte apoptosis

     Cartilage cell nucleus orange for apoptotic cells, blue for the normal cells. Specimens in the control group in the middle layer and the calcified cartilage layer, apoptotic cells.

    Low-energy group, after injury 4 d, 1,2-week specimens, cartilage intermediate layer of

    the transitional layer and apoptotic cells, the apoptotic rate between the control group had no statistical significance; 4 weeks after the specimen in apoptotic cells significantly

    reduced apoptosis rate were not statistically significant between groups (P

Report this document

For any questions or suggestions please email
cust-service@docsford.com