en تخصصي Special پژوهشي Research <p dir="ltr"><strong>Abstract </strong></p> <p dir="ltr"><strong>Objective:</strong> The previous studies indicated that the TLRs especially Toll-like receptor 4<span dir="RTL">) </span>TLR4<span dir="RTL"> (</span>are involved in the process of diabetes. The aim of the present research was to investigate the time course expression pattern of TLR4-a main component of innate immune system- in mRNA levels in the heart tissue of diabetic male wistar rats.</p> <p dir="ltr"><strong>Materials and Methods:</strong> In this research, adult Wistar rats (6-8 weeks old and 200-250 g weight) were mated and the pups were grown to 6-8 weeks old. Heart tissues were collected and analyzed by real-time PCR to evaluate the mRNA levels of TLR4. The mRNA levels of TLR4 in total heart tissue were evaluated in STZ-treated control rats in various times after diabetes induction.</p> <p dir="ltr"><strong>Results:</strong> Results showed that the up-regulation of TLR4 during the time course after diabetes induction as compared to the control. The abundant expression of TLR4, a major component of innate immunity system, provides strong evidence that TLRs play important roles in the pathogenesis and expansion of diabetes and it is possible that the expression of TLRs eventually lead to cardiovascular disease.</p> <p dir="ltr"><strong>Conclusion:</strong> The abundant expression of TLR4 which is major component of innate immunity system, provides strong evidence that TLRs play important roles in innate immunity and the pathogenesis and expansion of diabetes. It is possible that the expression of TLRs eventually lead to cardiovascular disease. The mechanisms for the increase in TLR expression and activity in diabetes have not been studied in depth. Modulating these TLRs could be beneficial in prevention of diabetic complications.</p> <p dir="ltr">&nbsp;</p> mRNA levels, Wistar rats, diabetic heart, Toll-like receptor 4 38 44 http://ijdo.ssu.ac.ir/browse.php?a_code=A-10-30-103&slc_lang=en&sid=1 Ali Dehghani Firoozabadi No Yazd Cardiovascular Research Center, Shahid Sadooghi University of Medical Sciences, Yazd, Iran.Department of Biology, Faculty of Science, Ferdowsi University of Mashhad, Mashhad-Iran. Samaneh Shojaeii Yes Immunology Section, Department Pathobiology, Faculty of Veterinary Medicine, Ferdowsi University of Mashhad, Mashhad-Iran. Biotechnology Section, Department of Pathology, Faculty of Veterinary Medicine, Ferdowsi University of Maashhad, Mashhad-Iran. Alireza Haghparast No Immunology Section, Department Pathobiology, Faculty of Veterinary Medicine, Ferdowsi University of Mashhad, Mashhad-Iran. Biotechnology Section, Department of Pathology, Faculty of Veterinary Medicine, Ferdowsi University of Maashhad, Mashhad-Iran. Hamidreza Dehghani Firoozabadi No Department of Biology, Faculty of Science, Isfahan University, Isfahan, Iran.