MODELS OF PARASPINAL MUSCLE DEGENERATION IN RATS: HIGH-FAT DIET AND PROLONGED COMPRESSION.OBJECTIVE

MODELS OF PARASPINAL MUSCLE DEGENERATION IN RATS
MODELS OF PARASPINAL MUSCLE DEGENERATION IN RATS: HIGH-FAT DIET AND PROLONGED COMPRESSION.OBJECTIVE

high-fat diet and prolonged compression
MODELS OF PARASPINAL MUSCLE DEGENERATION IN RATS: HIGH-FAT DIET AND PROLONGED COMPRESSION.OBJECTIVE
 psoas after keeping rats on a high-fat diet (obesity) or compressing their lumbar paraspinal muscles by binding the muscles using non-absorbable sutures.


 Materials and methods: The study was performed on 2-month-old male rats (n=15) into three groups of 5: control group (normal diet without any surgical interventions), high-fat diet (model I: 40-45% kcal fat), and paraspinal muscles compression (model II: paraspinal muscles were tied from L2 to S1 with non-absorbable sutures Nurolon® 3).  Results: 12 weeks from the beginning of the experiment, the high-fat diet rats weighed, on average, 22% (p=0.001) more than the control group rats. 
rats
psoas removed and histomorphometry analysis performed.



histomorphometry analysis
Materials and methods: The study was performed on 2-month-old male rats (n=15) into three groups of 5: control group (normal diet without any surgical interventions), high-fat diet (model I: 40-45% kcal fat), and paraspinal muscles compression (model II: paraspinal muscles were tied from L2 to S1 with non-absorbable sutures Nurolon® 3). 
surgical interventions
The experiment lasted for 90 days, after those fragments of the lumbar m. 
90 days
Results: 12 weeks from the beginning of the experiment, the high-fat diet rats weighed, on average, 22% (p=0.001) more than the control group rats. 
12 weeks
Results: 12 weeks from the beginning of the experiment, the high-fat diet rats weighed, on average, 22% (p=0.001) more than the control group rats. 
control group rats
Results: 12 weeks from the beginning of the experiment, the high-fat diet rats weighed, on average, 22% (p=0.001) more than the control group rats. 
high-fat diet rats
Similar degenerative changes such as uneven muscle fibre width and sarcoplasm colouring, 'wavy' and swollen fibres, loss of striation, karyopyknosis were observed in the lumbar paraspinal muscles in both models. 
uneven muscle fibre width
Similar degenerative changes such as uneven muscle fibre width and sarcoplasm colouring, 'wavy' and swollen fibres, loss of striation, karyopyknosis were observed in the lumbar paraspinal muscles in both models. 
sarcoplasm colouring
Similar degenerative changes such as uneven muscle fibre width and sarcoplasm colouring, 'wavy' and swollen fibres, loss of striation, karyopyknosis were observed in the lumbar paraspinal muscles in both models. 
'wavy' and swollen fibres
Similar degenerative changes such as uneven muscle fibre width and sarcoplasm colouring, 'wavy' and swollen fibres, loss of striation, karyopyknosis were observed in the lumbar paraspinal muscles in both models. 
loss of striation
Similar degenerative changes such as uneven muscle fibre width and sarcoplasm colouring, 'wavy' and swollen fibres, loss of striation, karyopyknosis were observed in the lumbar paraspinal muscles in both models. 
karyopyknosis
Fibrous tissue replaced muscle fibres in m. 
fibrous tissue replaced muscle fibres
Materials and methods: The study was performed on 2-month-old male rats (n=15) into three groups of 5: control group (normal diet without any surgical interventions), high-fat diet (model I: 40-45% kcal fat), and paraspinal muscles compression (model II: paraspinal muscles were tied from L2 to S1 with non-absorbable sutures Nurolon® 3).  multifidus in model II and was 12.66%.



model II