Effects of hyperhomocysteinemia on non-adrenergic non-cholinergic relaxation in isolated rat duodenum.
The effect of hyperhomocysteinemia induced by pretreatment with methionine 12 weeks prior to the study on the responses induced by gamma-aminobutyric acid (GABA), electrical field stimulation (EFS), and ATP have been evaluated in isolated rat duodenum. In the presence of adrenergic and cholinergic blockade, EFS (60 V, 1 ms, 1-3 Hz) induced frequency-dependent relaxations of the preparation. GABA and ATP also caused submaximal relaxation of the rat duodenum. The relaxations induced by GABA, EFS, and ATP were not significantly changed in duodenal tissues from hyperhomocysteinemic rats compared with control rats. GABA- and EFS-induced relaxations were inhibited by N-nitro-L-arginine methyl ester (L-NAME; 3 x 10(-4) M) in both hyperhomocysteinemic and control rats. On the other hand, L-NAME incubation did not affect ATP-induced relaxation. These results suggest that hyperhomocysteinemia does not cause an important impairment on non-adrenergic non-cholinergic innervation of the rat duodenum.
Karasu
Edibe
E
Department of Pharmacology, Akdeniz University Medical Faculty, Antalya, Turkey. edibekarasu@akdeniz.edu.tr
Sadan
Gülay
G
Tasatargil
Arda
A
D000109:Acetylcholine / Q000378:metabolism; D000255:Adenosine Triphosphate / Q000378:metabolism; D000818:Animals; D004195:Disease Models, Animal; D004386:Duodenum / Q000294:innervation*; D004558:Electric Stimulation; D017615:Enteric Nervous System / Q000187:drug effects / Q000201:enzymology / Q000503:physiopathology*; D004791:Enzyme Inhibitors / Q000494:pharmacology; D004837:Epinephrine / Q000378:metabolism; D006710:Homocysteine / Q000097:blood; D020138:Hyperhomocysteinemia / Q000139:chemically induced / Q000378:metabolism / Q000503:physiopathology*; D008297:Male; D008715:Methionine; D009126:Muscle Relaxation; D009130:Muscle, Smooth / Q000294:innervation*; D019331:NG-Nitroarginine Methyl Ester / Q000494:pharmacology; D019001:Nitric Oxide Synthase / Q000037:antagonists & inhibitors / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D013432:Sulfathiazoles; D005680:gamma-Aminobutyric Acid / Q000378:metabolism
D004791:Enzyme Inhibitors; D013432:Sulfathiazoles; D006710:Homocysteine; D005680:gamma-Aminobutyric Acid; D000255:Adenosine Triphosphate; D008715:Methionine; D019001:Nitric Oxide Synthase; D000109:Acetylcholine; C009342:succinylsulfathiazole; D019331:NG-Nitroarginine Methyl Ester; D004837:Epinephrine