Abstract
Morphine when subjected to a strong acid undergoes a chemical rearrangement becoming apomorphine, an isoquinoline derivative possessing very little narcotic action but a strong emetic action. Cannon 1 investigated the action of apomorphine upon the cat's stomach by the X-ray method. He observed that there was total inhibition of the cardial portion of the organ while there was contraction of the extreme end of the pyloric portion.
As no study of the action of apomorphine upon the intact intestine of the unanesthetized dog seems to have been done this series of experiments was undertaken.
The method was the same as that employed in another research 2 and will therefore not be described in detail here. The animals were the same as those used in the previous work, 5 having Thiry-Vella loops of the ileum and 3 of the jejunum. They were healthy animals in every respect. Apomorphine, in doses of 0.013 to 0.02 mg. per kg. body weight, dissolved in Ringer's solution, was injected intravenously 10 times in the 5 animals with Thiry-Vella loops of the ileum and 8 times in the 3 animals with jejunal loops.
In every experiment performed on the 3 dogs with Thiry-Vella loops of the ileum and the 4 with similar loops of the jejunum, apomorphine caused a rapid increase in the general tonus which was followed by an abrupt fall during a period of nausea. This was followed by a rather prolonged increase in general tonus. The periods of nausea were evidenced sometimes by vomiting and others simply by profuse salivation and licking reflexes depending on the size of the dose of the drug administered. The inhibition of the jejunum, during the period of nausea, was far more pronounced than that of the ileum. In many experiments, only salivation occurred and yet relaxation of the jejunum was very apparent.
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