عدم تغییر بیان ژن mef2c عضلة بطن چپ رت‌ها در پی فعالیت استقامتی

نوع مقاله : مقاله پژوهشی

نویسنده

استادیار فیزیولوژی ورزش، گروه تربیت بدنی دانشکده علوم انسانی، دانشگاه لرستان

چکیده

زمینه و هدف:ژنmef2cالقاءکنندة تارهای کند انقباض در عضلات اسکلتی است که در بسیاری از فرآیندهای سلولی درگیر است، فعالیت‌های استقامتی بر بیان این ژن در عضلة اسکلتی تأثیر می‌گذارد، هدف این مطالعه بررسی اثر دورة فعالیت استقامتی بر بیان ژن mef2cقلب بود.
مواد و روش‌ها: در این پژوهش تجربی 14 موش صحرایی تحت شرایط استاندارد (دما، چرخة روشنایی و تاریکی و دسترسی آزاد به آب و غذا) نگهداری و بعد از آشنا‌سازی با پروتکل فعالیت بدنی به صورت تصادفی به دو گروه کنترل و تجربی تقسیم شدند. گروه تجربی برنامه‌ای (14 هفته‌ای) فعالیت استقامتی را روی تردمیل اجرا کرد، سپس 48 ساعت پس از پایان آخرین جلسه فعالیت استقامتی بی‌هوش و تشریح شدند. قلب و بطن چپ آنها خارج شد. از روشReal time-PCR  برای اندازه‌گیری بیان ژن mef2cقلب (در ناحیه بطن چپ) استفاده شد. در پایان با استفاده از آزمون آماری t اطلاعات به دست آمده تجزیه‌و‌تحلیل شد.
یافته‌ها: نتیجة این پژوهش نشان داد فعالیت استقامتی موجب افزایش بیان ژن mef2cدر قلب گروه تجربی شد اما این افزایش در بیان ژن mef2cقلب گروه تجربی نسبت به گروه کنترل معنا‌دار (148/0p=) نبود.
نتیجه‌گیری: احتمالاً فعالیت استقامتی بر القای تارهای کند انقباض و در نتیجه افزایش آن‌ها در عضلة قلب تأثیر ندارد و از این طریق برای حفظ شرایط مطلوب بافت قلب، مکانیزم‌هایی در تلاشند که میزان بیان ژنmef2cدرسطح ثابتی حفظ شود.

کلیدواژه‌ها


عنوان مقاله [English]

Non change of Mef2c gene expression of rats left ventricle due to endurance activity

نویسنده [English]

  • Mohammad Fathi
Assistant Professor, Physical Education Department, Faculty of Humanities, Lorestan University, Lorestan, Iran
چکیده [English]

Background & Objectives: Mef2c gene induces slow twitch fibers in skeletal muscles which involves in various cellular processes. Endurance activity effects on expression of this genein skeletal muscle. The aim of this study was to investigate the effect of a course of endurance activity on Mef2c expression in cardiac .
Materials & Methods: In this experimental research, 14 rats under controlled conditions (temperature, light/dark (12:12) cycle, with ad Libitum access to food and water) were housed and randomly were divided into control and experimental groups after familiarization to endurance activity protocol. The experimental group performed 14 weeks endurance activity on motorized treadmill. They were anesthetized and sacrificed after 48 hours from the end of the last session of endurance activity. The heart and left ventricle of rats were removed. Using real time PCR, the expression levels of Mef2c gene was determined. The data were analyzed by t-test.
Results: Endurance activity induces the increase of Mef2c gene expression in heart but it was not significant (p= 0.148) in experimental group compared with control group.
Conclusion: The endurance training possibly does not effect on induction of slow twitch and increasing of them in heart muscle. Therefore, there are unknown mechanisms attempt that the rate of Mef2c gene expression do not much change, to maintain optimal conditions of heart tissue.

کلیدواژه‌ها [English]

  • endurance activity
  • left ventricle
  • Mef2c gene
  • muscular heart
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