The effect of tryptophan administration on ileum contractility and oxidant status in mice.
L-tryptophan (TRP) is the precursor amino acid for the synthesis of serotonin (5-HT). 5-HT is effective both on the food intake and gastrointestinal system contractility. The aim of this study was to search the effects of systemic TRP treatment on 5-HT levels of ileum and searching the effect of ileal contractility and oxidant status. Swiss-albino mice were divided into two groups: 1. Control, 2. TRP-treated (100 mg/kg/24 h, i.p., for 7 days). Body weights were recorded at the beginning and at the end of experiments. Acetylcholine-induced contractile responses in the isolated ileum were recorded on polygraph. Ileal tissue malondialdehyde and glutathione levels determined by spectrophotometric and ileal tissue 5-HT levels were measured by immunohistochemical methods. TRP treatment decreased body weight and increased ileal contractile response. In the TRP-treated group, ileum malondialdehyde levels increased and glutathione levels decreased. Immunohistochemical detection showed that ileal 5-HT levels were increased by TRP treatment. There is a relationship between increased oxidative stress and increased contractility in the ileal tissue of the TRP-treated animals. These effects may be related to increased ileal 5-HT synthesis.
Ozer
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C
Department of Physiology, Faculty of Medicine, University of Gazi, Ankara, Turkey. ozercigdem@yahoo.co.uk
Gönül
B
B
Ercan
Z S
ZS
Take
G
G
Erdoğan
D
D
D000109:Acetylcholine / Q000494:pharmacology; D000818:Animals; D018687:Antidepressive Agents, Second-Generation / Q000008:administration & dosage*; D018678:Cholinergic Agents / Q000494:pharmacology; D004435:Eating / Q000187:drug effects; D005978:Glutathione / Q000378:metabolism; D007082:Ileum / Q000378:metabolism*; D008297:Male; D008315:Malondialdehyde / Q000378:metabolism; D051379:Mice; D009119:Muscle Contraction / Q000187:drug effects*; D009924:Organ Culture Techniques; D018384:Oxidative Stress / Q000187:drug effects*; D012701:Serotonin / Q000096:biosynthesis; D014364:Tryptophan / Q000008:administration & dosage*
D018687:Antidepressive Agents, Second-Generation; D018678:Cholinergic Agents; D012701:Serotonin; D008315:Malondialdehyde; D014364:Tryptophan; D005978:Glutathione; D000109:Acetylcholine