Effects of restraint stress and nitric oxide synthase inhibition on learning and strategy preference in young adult male rats.

Objective: The aim of this study was to investigate the effects of restraint stress and nitric oxide synthase (NOS) inhibition by Naomega;Nitro-L-Arginine (LNA) on learning and strategy preference. Material and Methods: Rats were randomly divided into four groups (Saline, Saline+Stress, LNA, LNA+Stress). Stress was applied for one hour in glass cylinders during 13 days. One hour after this stress application, water maze experiments were started. Injections (saline 1 ml/kg or 50 mg/kg LNA) were given 10 minutes before each experiment. The platform was kept visible or hidden (on the 4th, 8th, 12th days) at the same position. On the 13th day the platform was located on the opposite quadrant. Results: Saline groups exhibited significantly better performances (F(1.31)=174.038 palt;0.05) at the beginning compared to the NOS inhibited groups. For initial hidden platform days; stress was determined as an impairment factor (F(1.31)=5.190 p=0.012). At the end, acquisition occurred on both visible and hidden platform days for all groups. There was no significant strategy preference difference between the groups.Development of the stress and NOS inhibition impairments were seen, particularly at different periods of the acquisition. Conclusion: NOS inhibition did not worsen restraint stress-induced learning impairments in rats. Lack of effect may be explained by the antidepressive consequences of NOS inhibition. Turkish Baslik: Kisitlama stresi ve nitrik oksit sentaz inhibisyonunun genc eriskin erkek sicanlarda ogrenme ve strateji tercihi uzerine etkileri Anahtar Kelimeler: Diabetes mellitus, cynodon dactylon, elektromanyetik alan, insulin, glukoz Amac: Prospektif, randomize ve cilf kor calismada septorinoplasti (SRP) ve endoskopik sinus cerrahisi (ESC) ameliyatlarindan sonra levobupivakain ve tramadol infiltrasyonunun postoperatif analjezik etkilerinin arastirilmasi amaclandi. Gerec ve Yontemler: Calismaya elektif olarak ESC ve SRP operasyonlari gerirecek ASA I-III sinifi altmis eriskin hasta alindi. Anestezi induksiyonu intravenoz propofol 2-2.5 mg/kg-1, rokuronyum bromid 0.6 mg/kg-1, and fentanil 1 amu;g/kg-1 ile gerceklestirildi. Idame %2 sevofluran ile N2O/O2 karisimi (FiO2: 35%) ile saglandi. Operasyondan 10 dakika once cerrahi sahaya tramadol 0.5 mg/kg-1(Group T: n= 20), levobupivakain %0.25(Group L: n= 20), ve lidokainin %1(Group C: n= 20) adrenaline solusyonu 1/200000 infiltre edildi (ESC icin 5 mL ve SRP icin10 mL). Postoperatif donemde hastalarin tumune hasta kontrollu analjezi cihazi ile fentanil uygulandi (bolus doz: 15 amu;g ve kilit araligi:10 dak). Agri postoperative ilk 24 saatte 11 dereceli vizuel analog skala (VAS) ile 4 saat ara ile degerlendirildi. Postoperatif donemde analjezik gereksinim, opioid tuketimi ve yan etkiler belirlenerek kaydedildi. Bulgular: Tramadol verilen grubun fentanil gereksinim ve tuketimi istatistiksel acidan farkli bulundu. 24 saatlik fentanyl dozlari Grup C, L ve T icin sirasi ile 345.2 aplusmn; 168.8,6 amu;g, 221.1 aplusmn; 120.6 amu;g; and 184.1 aplusmn; 130,3 amu;g (p= 0.002) olarak belirlendi. Tramadol ve kontrol grubunun fentanil gereksinimlerinde 16, 20 ve 24. saat peryotlarda (p= 0.012, p= 0.004. ve p= 0.002) farklilik saptandi. Yan etki profili benzerdi. Sonuc: Bulgularimiz ESC ve SRP operasyonlarindan once preemptif tramadol infiltrasyonunun levobupivakainin etkili, pratik ve guvenli bir alternatifi oldugunu dusundurmektedir.