PENGARUH FREKUENSI STRES FISIK PADA KADAR LACTATE DEHYDROGENASE (LDH) TOTAL DAN JUMLAH NEUROMUSCULAR JUNCTION (NMJ) OTOT PAHA TIKUS BETINA DENGAN DIET ATHEROGENIK

Abstract

Introduction: Atherogenic diet increased serum lactate dehydrogenase (LDH) levels and altered muscle structure so does physical stress. However, study on the effect of various frequency of physical stress with atherogenic diet on serum LDH and muscles structure especially on the number of neuromuscular junction (NMJ) have not been conducted.

Methods: Female Wistar rats (5 weeks old) were divided into control and treatment groups. Control groups consist of Pre-Treatment (KPP, n=5), Positive (KP, n=5) and Negative control groups (KN, n=5) which were given atherogenic diet for 6 weeks (KPP) or 10 weeks (KP) and standard diet for 10 weeks (KN). Treatment groups were given atherogenic diet and 4 weeks of physical stress in form of forced swimming for 5 minutes daily (KSH, n = 5), alternate (KDH, n = 5) and twice a week (KSK, n = 5). At 15 weeks of age, KN, KP, KSH, KDH and KSK groups were euthanized and samples were collected. LDH levels were measured using spectrophotometry while thigh muscles histology were assessed using HE staining and analyzed using Image J.

Results: Atherogenic diet does not affect the number of NMJ (49.98 + 15.10) KN and (34.77 + 2.58) KP but significantly increases total LDH levels (407.40 + 174.38) KN and (1523.40 + 613.17) KP. Various frequencies of physical stress did not significantly affect serum LDH levels. However, in number of NMJ, KSK group were significantly different from KP suggesting that physical activity changes the muscle histological structure. Correlation analysis showed non-significant negative relationship between NMJ and serum LDH level suggesting that physical stress during atherogenic diet must be carried out at the right frequency to obtain the best results.

Conclusion: The atherogenic diet affects serum LDH levels but not NMJ number while physical stress affect number of NMJ but not serum LDH levels.