THE ACTION OF URETHANE ON INVOLUNTARY MUSCLE

¹ From the Pharmacological Laboratory, Oxford

Urethane in doses between 1:45 and 1:200 has caused diminution in tone and in rhythmic movements in involuntary muscle, as studied in isolated tissue preparations. In the rabbit it has had effect on the mesenteric vein, intrapulmonary bronchus, pulmonary artery, inferior vena cava, uterus, spleen, and small intestine. In the ox it has relaxed the mesenteric vein. It has had no effect on the systemic aorta or gall-bladder of the rabbit. It has relaxed the mesenteric artery and intrapulmonary bronchus in the sheep. The action of drugs which normally cause contraction of some of the muscular tissues used is lessened or abolished. This general depressant action on isolated smooth muscle preparations makes more interesting the lack of action of urethane on the systemic blood pressure, which was first pointed out by Schmiedeberg (3) in 1885.