Research Information System
Kafkas Universitesi Veteriner Fakultesi Dergisi, vol.19, no.6, pp.949-954, 2013 (SCI-Expanded, Scopus, TRDizin)
This study was designed to investigate the effect of 17β-estradiol on small intestinal motility of ovariectomized rats and the possible role of nitric oxide (NO) in this activity. A total of 24, 3 to 6 month-old female Sprague Dawley rats (270±20 g) were ovariectomized and divided into four groups as one control and three experimental groups. The control group received 0.2 mL, sesame oil once daily for three days, whereas the experimental groups were treated with 25, 50 and 100 μg/rat intramuscular 17β-estradiol, respectively. The rats were sacrificed by cervical dislocation under anaesthesia 18 h after the termination of last treatment. Immediately, duodenum, jejunum and ileum were isolated for organ bath contractility experiments to evaluate isometric smooth muscle motility in vitro. It was observed that application of 100 μg/rat 17β-estradiol showed a decreasing tension in duodenum, whereas none of the different doses of 17β-estradiol showed any significant difference in jejunum. The application of 50 and 100 μg/rat 17β-estradiol decreased the spontaneous contractile tension of ileum. However, L-arginine (105M), 8-Br-cGMP (106) and SNP (103M) decreased the spontaneous contractions of smooth muscle of duodenum, jejunum and ileum. Moreover, it was demonstrated that 17β-estradiol decreased the relaxing activity of L-arginine and 8-Br-cGMP but increased the activity of SNP in dose dependent manner. In conclusion, it is suggested that 17β-estradiol has a relaxative effect in duodenum and ileum and particularly inhibits the activity of cGMP-PK. However, endogenous NO-NOS pathway mediated by 17β-estradiol may play a key role in secretory and/or ciliary activity of intestinum.