Principle of Bioassay of 5-HT (Serotonin)
5-HT (Serotonin) also causes smooth muscle contraction in certain tissues (e.g., rat fundus strip, guinea pig ileum).
The bioassay measures the contractile response to 5-HT in an isolated tissue preparation. (Bioassay of 5-HT) (Serotonin)
Methods
Rat Fundus Strip or Guinea Pig Ileum
Procedure:
Mount the tissue in an organ bath.
Apply standard 5-HT in graded doses, record the contractile response. Wash out between doses.
Repeat with the test preparation.
Potency Determination: Compare dose-response curves, typically focusing on the EC50 or the dose producing a specific level of contraction (e.g., 50% maximal).