Effects of hypothyroidism on the response of the rat colon to morphine.
Isolated terminal colon strips obtained from rats, made hypothyroid by methimazole treatment, were almost completely insensitive to the contractile effects of morphine as compared to strips from control animals. This low morphine sensitivity was accompanied by a significant (40%) reduction in the tissue sulfatide content. Although colon strips from hypothyroid rats showed a reduction of the contractile effects of acetylcholine, the decrease was considerably less than that noted for morphine. The addition of 6.6 X 10(-5) M tri-iodothyronine to colons from hypothyroid rats largely restored the tissue sensitivity to morphine. These results suggest that sulfatides could be linked to the in vitro effects of morphine in the colon.
D000109:Acetylcholine / Q000494:pharmacology; D000818:Animals; D001835:Body Weight / Q000187:drug effects; D003106:Colon / Q000187:drug effects; D007037:Hypothyroidism / Q000503:physiopathology*; D066298:In Vitro Techniques; D008297:Male; D008713:Methimazole / Q000494:pharmacology; D009020:Morphine / Q000494:pharmacology*; D009119:Muscle Contraction / Q000187:drug effects*; D009130:Muscle, Smooth / Q000187:drug effects*; D051381:Rats; D013433:Sulfoglycosphingolipids / Q000494:pharmacology
D013433:Sulfoglycosphingolipids; D008713:Methimazole; D009020:Morphine; D000109:Acetylcholine