title: MAPK immunoreactivity in streptozotocin-induced diabetic rat testis.
abstract: OBJECTIVE
  To evaluate the alterations of two mitogen-activated protein kinases (MAPK)s, extracellular signal regulated kinase (ERK) and c-Jun NH2 terminal kinase (JNK), in the testes of male rats with experimental diabetes.
  
  
  METHODS
  Twenty males Sprague-Dawley rats were randomly divided into a control group (n=8) and a diabetes group (administration of 40 mg/kg/day streptozotocin (STZ) for five sequential days, n=12). After six weeks, testicular biopsy samples were obtained for light microscopy and immunohistochemical methods.
  
  
  RESULTS
  The PCNA (proliferating cell nuclear antigen) index was significantly decreased in the diabetes group (p=0.004) when compared to the control group. Both total (t)-ERK and phosphor (p)-ERK immunoreactivities were significantly decreased in the diabetes group (p=0.004, p<0.001, respectively). The t-JNK immunoreactivity was unchanged in both groups (p=0.125), while p-JNK immunoreactivity was significantly increased in the diabetic group (p=0.002).
  
  
  CONCLUSIONS
  The decrease of androgen levels in the course of diabetes may contribute to the decrease of the immunoreactivities of t-ERK and p-ERK. JNK may be activated due to the changes in various cytokines and chemochines that participate in the oxidative stress process of diabetes. Therefore, testicular apoptosis may occur and lead to infertility associated with diabetes.
authors.affiliation: Department of Histology and Embryology, Faculty of Medicine, Namık Kemal University, Tekirdag, Turkey.
authors.forename: Yelız Bozdemır
authors.initials: YB
authors.lastname: Donmez
authors.affiliation: Department of Histology and Embryology, Faculty of Medicine, Trakya University, Edirne, Turkey.
authors.forename: Gulnur
authors.initials: G
authors.lastname: Kizilay
authors.affiliation: Department of Histology and Embryology, Faculty of Medicine, Trakya University, Edirne, Turkey.
authors.forename: Yeter
authors.initials: Y
authors.lastname: Topcu-Tarladacalisir
mesh_terms: D000818:Animals; D017209:Apoptosis; D001706:Biopsy; D003921:Diabetes Mellitus, Experimental / Q000150:complications / Q000378:metabolism*; D048049:Extracellular Signal-Regulated MAP Kinases / Q000378:metabolism*; D007150:Immunohistochemistry; D007248:Infertility, Male / Q000209:etiology / Q000378:metabolism; D048031:JNK Mitogen-Activated Protein Kinases / Q000378:metabolism*; D008297:Male; D011897:Random Allocation; D017208:Rats, Wistar; D013311:Streptozocin; D013737:Testis / Q000378:metabolism* / Q000473:pathology
chemical_list: D013311:Streptozocin; D048049:Extracellular Signal-Regulated MAP Kinases; D048031:JNK Mitogen-Activated Protein Kinases