Article contents
An experimental investigation on the action of Coramine
Published online by Cambridge University Press: 15 May 2009
Extract
1. Coramine increases the sensitivity of the central nervous system, particularly the centres situated in the medulla.
2. In large doses, Coramine increases the activity of the spinal cord, producing muscular twitchings of the limbs and body which, when severe, take on the character of convulsive movements.
3. There is a wide margin of safety between the therapeutic and lethal doses.
4. Lethal doses produce convulsions and respiratory failure owing to the involvement of the muscles of respiration.
5. Coramine acts as a powerful respiratory stimulant and is able to over-come the depressant effects of morphine on the respiratory centre in the medulla.
6. Small doses of Coramine raise the blood pressure which is due to a peripheral vasoconstriction. This is partly due to a stimulating effect of the drug on the medulla and to some extent to a peripheral action on either the vasoconstrictor nerves or the arterial muscle. Slightly larger but moderate doses sometimes cause a primary relaxation of the arterioles lasting a few seconds, which may cause a small short-lived fall in blood pressure which is never serious in the normal animal. The rise in blood pressure may last ¼–2 hr., according to the dosage employed.
7. Small amounts of Coramine may increase the amplitude and stroke volume of the heart. This effect was never constant. Larger but moderate doses always produced a diminution in cardiac stroke volume with a decrease in cardiac output. The same effect is seen when large doses are employed. This appears to be the cause of the prolonged lowering of the blood pressure following the administration of large doses of Coramine.
8. Coramine dilates the coronary vessels of the myocardium producing an increase in coronary flow.
9. Coramine lowers the pressure in the right auricle of the heart and the pulmonary artery.
10. Coramine has no effect upon intestinal movements except, when large doses are employed, it causes a slight diminution in the amplitude of the movements with a small increase in muscular tone.
- Type
- Research Article
- Information
- Copyright
- Copyright © Cambridge University Press 1940
References
REFERENCES
- 6
- Cited by