title: Penile constitutive nitric oxide synthase expression in rats exposed to unpredictable chronic mild stress: role of inflammation.
abstract: Chronic psychological stress cause erectile dysfunction (ED). Considering recent evidence that tumor necrosis factor-α (TNF-α) levels are increased in serum of patients with ED, the present study investigated the effects of infliximab (a TNF-α blocker) on endothelial nitric oxide synthase (eNOS) and neuronal NOS (nNOS) immunoreactivity of rat penile corpus cavernosum in unpredictable chronic mild stress (UCMS). Male adult rats were randomly divided into three groups (n=8 per group): Control, UCMS and UCMS+infliximab. Control and UCMS groups received physiological saline, UCMS+infliximab group received infliximab (5 mg kg-1per week, intraperitoneally) during 8 weeks of UCMS. UCMS and UCMS+infliximab groups were subjected to different types of stressors, which were randomly applied four to five times during this time period. After 8 weeks, penile eNOS and nNOS expressions were determined immunohistochemically. In UCMS group, nNOS and eNOS immunoreactivity was found to be decreased in penile corpus cavernosum compared with the control group. Whereas in infliximab treatment group eNOS and nNOS immunoreactivity increased compared with the UCMS group. These findings support that UCMS decreases penile constitutive NOS expression via TNF-α, which may contribute to the development of ED. Blockage of TNF-α actions may represent an alternative therapeutic approach for ED in chronic psychological stress.
authors.affiliation: Medical Faculty, Department of Pharmacology, Kocaeli University, Kocaeli, Turkey.
authors.forename: T D
authors.initials: TD
authors.lastname: Şahin
authors.affiliation: Medical Faculty, Department of Histology and Embryology, Kocaeli University, Kocaeli, Turkey.
authors.forename: Y
authors.initials: Y
authors.lastname: Yazır
authors.affiliation: Medical Faculty, Department of Pharmacology, Kocaeli University, Kocaeli, Turkey.
authors.forename: T
authors.initials: T
authors.lastname: Utkan
authors.affiliation: Medical Faculty, Department of Pharmacology, Kocaeli University, Kocaeli, Turkey.
authors.forename: S S
authors.initials: SS
authors.lastname: Göçmez
authors.affiliation: Medical Faculty, Department of Dermatology, Kocaeli University, Kocaeli, Turkey.
authors.forename: D
authors.initials: D
authors.lastname: Bayramgürler
mesh_terms: D000818:Animals; D007172:Erectile Dysfunction / Q000209:etiology*; D007249:Inflammation / Q000378:metabolism*; D000069285:Infliximab / Q000009:adverse effects*; D008297:Male; D052247:Nitric Oxide Synthase Type II / Q000378:metabolism*; D052250:Nitric Oxide Synthase Type III / Q000378:metabolism*; D010410:Penile Erection / Q000187:drug effects; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D013315:Stress, Psychological / Q000150:complications*
chemical_list: D000069285:Infliximab; D052247:Nitric Oxide Synthase Type II; D052250:Nitric Oxide Synthase Type III; C496318:Nos2 protein, rat; C496316:Nos3 protein, rat