초록

이 연구에서는 8주간의 저항성 운동 시 크레아틴, 류신의 투여가 근 단백질 합성과 근비대에 어떠한 영향을 미치는지 규명하는데 그 목적이 있다. 실험동물은 SD계 흰쥐 수컷 32마리를 사용하였으며, 대조군(CON), 운동군(E), 운동과 크레아틴 투여군(EC), 운동과 크레아틴, 류신 투여군(ECL)으로 분류하였다. 저항성 운동은 점진적으로 증가시킨 중량을 꼬리에 연결하여 사다리를 오르는 방법을 이용하였으며(주 3회), 보조제 투여는 크레아틴은 250㎎/kg, 크레아틴+류신은 250+250㎎/kg의 양을 매일 구강 투여하였다. 실험 결과, 체중은 모든 집단에서 실험 초기에 비해 유의하게 증가하였고(p<.001), CON군의 체중이 저항성 운동을 실시한 세 집단의 체중보다 유의하게 많이 나갔다(p<.05). plantaris 무게는 E군이 CON군에 비해 유의하게 증가하였으며(p<.05), FHL 근육무게는 운동을 실시한 세 집단이 CON군에 비해 유의하게 증가하였다(p<.05). 또한 E군이 EC군, ECL군보다 유의하게 증가하였다(p<.05). 최대근력은 저항성 운동을 실시한 세 집단 모두 실험 초기에 비해 유의하게 증가하였으며(p<.001), 집단 간 차이는 없었다. Phospho-Akt 발현은 보조제를 투여한 EC군과 ECL군이 유의하게 감소하였으며(p<.05), Phospho-mTOR는 유의한 차이가 없이 증가하는 경향을 보였다. 따라서 저항성 운동은 근육량의 증가와 근력 향상에 긍정적인 영향을 미치지만, 추가적으로 처치한 크레아틴과 류신의 영향은 미비한 것으로 판단된다. 그러나 세포내 수준에서 phospho-mTOR 단백질 발현이 증가하는 경향을 보임으로써 그 가능성을 확인할 수 있었고, 추후에는 단백질 합성에 관여하는 다양한 요인들을 세밀하게 관찰하는 연구가 필요할 것으로 사료된다.

키워드

저항성 운동, 크레아틴, 류신, 근 단백질 합성, Akt, mTOR, 근 비대

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