The vasoconstrictor felypressin is added to some local anaesthetics (i.e. prilocaine) in a concentration of 0.003 i.u./ml. Felypressin is a non catecholamine vasoconstrictor that is chemically related to vasopressin, the posterior pituitary hormone. Felypressin is a V1 Agonist - and will thus have affects at all V1 receptors. It will however have its main physiological effects on vascular SMC's due to the form in which it is administered. V1 receptors are found in various sites around the body, the major points include: more...
Muscle (both vascular and non-vascular smooth muscle)
Another example of a V1 Agonist is Terlipressin - which is used in Oesophageal Varices.
"Vasopressin analogues and treatments", Prof Buckingham, ICSM - adapted by JHPatel
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