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n Cardiovascular Journal of South Africa - Proposed mechanisms for the anabolic steroid-induced increase in myocardial susceptibility to ischaemia / reperfusion injury : cardiovascular topic

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Abstract

Androgenic anabolic steroids (AAS) are often used by athletes to enhance athletic performance but are strongly associated with detrimental cardiovascular effects including sudden cardiac death. &lt;br&gt;&lt;I&gt;Hypothesis:&lt;/I&gt; AAS use increases myocardial susceptibility to ischaemia / reperfusion injury. &lt;br&gt;&lt;I&gt;Methods:&lt;/I&gt; Rats were trained (swimming) with or without intramuscular injection of nandrolone laurate (0.375 mg/kg). Untrained rats with or without nandrolone served as controls. Hearts were mounted on the Langendorff perfusion apparatus and mechanical function was measured before and after 20-min normothermic global ischaemia. Myocardial tissue samples were collected for determination of tissue cyclic nucleotide and TNF<SPAN lang=AF style="FONT-FAMILY: Symbol; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'; mso-char-type: symbol; mso-symbol-font-family: Symbol"><SPAN style="mso-char-type: symbol; mso-symbol-font: Symbol"&gt;a&lt;/SPAN&gt;&lt;/SPAN&gt; concentrations. &lt;br&gt;&lt;I&gt;Results:&lt;/I&gt; Anabolic steroids decreased the rate pressure product (RPP) of the exercise-trained rat heart [34 582 &lt;u&gt;+&lt;/u&gt; 1 778 mmHg/min vs 28 868 &lt;u&gt;+&lt;/u&gt; 2 446 mmHg/min for exercise-trained steroid-treated hearts (&lt;I&gt;p&lt;/I&gt; < 0.05)]. Reperfusion RPP was lower in both the sedentary, and the exercise-trained, steroid-treated hearts than in their concurrent vehicle-treated controls (18 276 &lt;u&gt;+&lt;/u&gt; 2 026 mmHg/min vs 12 018 &lt;u&gt;+&lt;/u&gt; 1 725 mmHg/min for sedentary steroid-treated hearts and, 21 892 &lt;u&gt;+&lt;/u&gt; 2 912 mmHg vs 12 838 &lt;u&gt;+&lt;/u&gt; 1 536 mmHg/min for exercise-trained steroidtreated hearts). Myocardial TNF<SPAN lang=AF style="FONT-FAMILY: Symbol; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'; mso-char-type: symbol; mso-symbol-font-family: Symbol"><SPAN style="mso-char-type: symbol; mso-symbol-font: Symbol"&gt;a&lt;/SPAN&gt;&lt;/SPAN&gt; [267.75 &lt;u&gt;+&lt;/u&gt; 44.25 pg/g vs 190.00 &lt;u&gt;+&lt;/u&gt; 15.75 pg/g (&lt;I&gt;p&lt;/I&gt; < 0.05)] and cAMP concentrations [406.04 &lt;u&gt;+&lt;/u&gt; 18.41 pmol/g vs 235.6 &lt;u&gt;+&lt;/u&gt; 43.26 pmol/g (&lt;I&gt;p&lt;/I&gt; < 0.05)] were elevated in the steroid-treated hearts when compared with their untreated counterparts. &lt;br&gt;&lt;I&gt;Conclusions:&lt;/I&gt; Supraphysiological doses of anabolic steroids, whether taken during exercise training or under sedentary conditions increase myocardial susceptibility to ischaemia / reperfusion injury in our model. This increased susceptibility may be related to steroid-induced increases in the pre-ischaemic myocardial cAMP concentrations and / or increases in both pre-ischaemic and reperfusion TNF<SPAN lang=AF style="FONT-FAMILY: Symbol; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'; mso-char-type: symbol; mso-symbol-font-family: Symbol"><SPAN style="mso-char-type: symbol; mso-symbol-font: Symbol"&gt;a&lt;/SPAN&gt;&lt;/SPAN&gt; concentrations.

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/content/cardio/16/1/EJC23966
2005-01-01
2016-12-08
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