21. The attained high levels of cAMP persist during histamine release. 22. Antibiotics like polymyxin are also found to stimulate histamine release. 23. Histamine causes dilation and increased permeability of capillaries close to the basophil.24. Harmaline is known to act as a histamine N-methyltransferase inhibitor. 25. Clemastine inhibits both the vasoconstrictor and vasodilator effects of histamine . 26. Antihistamines do not chemically inactivate or prevent the normal release of histamine . 27. Levocetirizine is an inverse agonist that decreases activity at histamine H1 receptors. 28. It does not prevent the actual release of histamine from mast cells. 29. Trimethaphan causes a histamine release which further lowers blood pressure. 30. Alcohol is known to have close interactions with histamine release.
