Sodium bicarbonate supplementation prevents cardiac hypertrophy in male rats exposed to high intensity swim exercise via inhibition of lactate dehydrogenase activity


Swim exercise, Cardiac hypertrophy, Sodium bicarbonate, CRP, LDH, Rat


Background: Cardiac hypertrophy is linked with ventricular arrhythmia and can be fatal
among athletes engaged in high intensity exercise. This study investigates the effect of sodium
bicarbonate on cardiac hypertrophy induced by swim exercise in male Wistar rats. Methods:
Forty male Wistar (100-150 g) randomly divided into 5 groups 1-5 (n =8) were used. Group 1
was the control sedentary animals while groups 2-3 and 4-5 were exercised at low or high
intensity, respectively. Groups 1,2 and 4 received distilled water while groups 3 and 5 received
sodium bicarbonate (250 mg/kg, p.o) daily. Exercise was carried out by swimming in a
temperature regulated water tank 5 days/ week for 8 weeks. The intensity was varied by
attaching 5% body weight load to the tail of the high intensity exercise groups while the low
intensity groups were unloaded. Body weight was monitored weekly. Blood samples were
obtained for plasma lipid profile, C-Reactive Protein (CRP) and Lactate Dehydrogenase
(LDH) concentration. Cardiac hypertrophy was determined from the heart weight to tail length
(HW:TL) ratio. Data were presented as Mean ± SEM. Results: Final body weights of all
exercised groups were not different when compared with their initial weight. Cholesterol and
low-density lipoprotein were decreased in the high intensity exercise group treated with
sodium bicarbonate. Triglyceride level was not different across all groups while High-density
lipoprotein increased in the low intensity untreated and low intensity treated groups. CRP level
was not different across all groups while LDH activity was significantly decreased in the high
intensity exercised group treated with sodium bicarbonate. Sodium bicarbonate treatment also
caused significant decrease in HW:TL ratio in the treated high intensity exercise group
compared with their corresponding untreated group. Conclusion: Sodium bicarbonate
supplementation ameliorated swim exercise-induced cardiac hypertrophy in male Wistar rats
through a mechanism that probably involves lactate dehydrogenase activity.