Investigation of acute effects of aflatoxin on rat proximal and distal colon spontaneous contractions.
Aflatoxins are one of the most potent toxic, mutagenic, teratogenic, cancerogenic, and immunosuppresive substances that naturally occurring contaminants of food. There are some studies in various animal species that have reported aflatoxin effects on gastrointestinal systems, but acute effects of aflatoxins have not been clearly investigated. In this study, we aimed to investigate the acute gastrointestinal effects of total aflatoxin on rat isolated proximal and distal colon. Aflatoxin was given cumulatively at 10(-8)-10(-5)M concentrations and the amplitude and frequency of proximal and distal colon contractions were increased significantly. In the presence of atropine sulfate (23.6 nM) and morphine (0.3 microM) the amplitude and frequency of aflatoxin induced spontan contractions in the proximal and distal colon decreased significantly, on the other hand, L-NNA (0.3 microM) increased contractions' amplitude and frequency significantly in the proximal colon but not in the distal colon. In conclusion, aflatoxin may increase the amplitude and frequency of contractions by increasing muscarinic activity or by decreasing NO synthase and/or release in proximal colon and by increasing muscarinic activity in the distal colon. These findings of aflatoxin on isolated rat proximal and distal colon may explain their acute gastrointestinal effects in humans and animals.
Gursoy
Nevcihan
N
Cumhuriyet University Faculty of Engineering, Department of Food Engineering, 58140 Sivas, Turkey. gursoy_gu@hotmail.com
Durmus
Nedim
N
Bagcivan
Ihsan
I
Sarac
Bulent
B
Parlak
Ahmet
A
Yildirim
Sahin
S
Kaya
Tijen
T
D000348:Aflatoxins / Q000633:toxicity*; D000701:Analgesics, Opioid / Q000494:pharmacology; D000818:Animals; D001285:Atropine / Q000494:pharmacology; D003106:Colon / Q000187:drug effects*; D004791:Enzyme Inhibitors / Q000494:pharmacology; D007537:Isometric Contraction / Q000187:drug effects; D008297:Male; D009020:Morphine / Q000494:pharmacology; D018727:Muscarinic Antagonists / Q000494:pharmacology; D009119:Muscle Contraction / Q000187:drug effects*; D009130:Muscle, Smooth / Q000187:drug effects*; D019331:NG-Nitroarginine Methyl Ester / Q000494:pharmacology; D019001:Nitric Oxide Synthase / Q000037:antagonists & inhibitors; D011189:Potassium Chloride / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar
D000348:Aflatoxins; D000701:Analgesics, Opioid; D004791:Enzyme Inhibitors; D018727:Muscarinic Antagonists; D011189:Potassium Chloride; D009020:Morphine; D001285:Atropine; D019001:Nitric Oxide Synthase; D019331:NG-Nitroarginine Methyl Ester