Optimization of pulsed electromagnetic field therapy for management of arthritis in rats.
Studies were undertaken to find out the effects of low frequency pulsed electromagnetic field (PEMF) in adjuvant induced arthritis (AIA) in rats, a widely used model for screening potential therapies for rheumatoid arthritis (RA). AIA was induced by an intradermal injection of a suspension of heat killed Mycobacterium tuberculosis (500 mug/0.1 ml) into the right hind paw of male Wistar rats. This resulted in swelling, loss of body weight, increase in paw volume as well as the activity of lysosomal enzymes viz., acid phosphatase, cathepsin D, and beta-glucuronidase and significant radiological and histological changes. PEMF therapy for arthritis involved optimization of three significant factors, viz., frequency, intensity, and duration; and the waveform used is sinusoidal. The use of factorial design in lieu of conventional method resulted in the development of an ideal combination of these factors. PEMF was applied using a Fransleau-Braunbeck coil system. A magnetic field of 5 Hz x 4 muT x 90 min was found to be optimal in lowering the paw edema volume and decreasing the activity of lysosomal enzymes. Soft tissue swelling was shown to be reduced as evidenced by radiology. Histological studies confirmed reduction in inflammatory cells infiltration, hyperplasia, and hypertrophy of cells lining synovial membrane. PEMF was also shown to have a membrane stabilizing action by significantly inhibiting the rate of release of beta-glucuronidase from lysosomal rich and sub-cellular fractions. The results indicated that PEMF could be developed as a potential therapy in the treatment of arthritis in humans.
Kumar
Venkatachalam Senthil
VS
Department of Pharmacology and Toxicology, Madras Veterinary College, Vepery, Chennai, India.
Kumar
Dilly Ashok
DA
Kalaivani
Kalyanasundaram
K
Gangadharan
Akkalayi Chandrapuram
AC
Raju
K V S Narayana
KV
Thejomoorthy
Pammi
P
Manohar
Bhakthavatchalam Murali
BM
Puvanakrishnan
Rengarajulu
R
D000135:Acid Phosphatase / Q000032:analysis / Q000528:radiation effects; D000818:Animals; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000627:therapeutic use; D001169:Arthritis, Experimental / Q000276:immunology / Q000473:pathology / Q000532:radiotherapy*; D001172:Arthritis, Rheumatoid; D001835:Body Weight; D002402:Cathepsin D / Q000032:analysis / Q000528:radiation effects; D004008:Diclofenac / Q000627:therapeutic use; D004487:Edema / Q000276:immunology / Q000473:pathology / Q000532:radiotherapy; D004574:Electromagnetic Fields; D005528:Foot / Q000473:pathology / Q000528:radiation effects; D005966:Glucuronidase / Q000032:analysis / Q000528:radiation effects; D006614:Hindlimb / Q000473:pathology / Q000528:radiation effects; D006965:Hyperplasia; D006984:Hypertrophy; D008247:Lysosomes / Q000201:enzymology / Q000528:radiation effects; D008297:Male; D009169:Mycobacterium tuberculosis / Q000276:immunology; D051381:Rats; D017208:Rats, Wistar; D013583:Synovial Membrane / Q000473:pathology / Q000528:radiation effects
D000894:Anti-Inflammatory Agents, Non-Steroidal; D004008:Diclofenac; D000135:Acid Phosphatase; D005966:Glucuronidase; D002402:Cathepsin D