Evaluation of Hyoscine ED50 on Pilocarpine-Induced Contractility of Isolated Guinea Pig Ileum

1. Evaluation of Hyoscine ED50 on Pilocarpine-Induced Contractility of Isolated Guinea Pig Ileum

2. Principle:

Isolated guinea pig ileum has muscarinic acetylcholine (Ach)
receptors which mediate the stimulatory effects of Ach and
other cholinomimetics as pilocarpine.
Antimuscarinics
suppress cholinomimetics-induced
contractility of this preparation.

3. Isolated Tissue Preparations

4.

Assignment:
Different concentrations of hyoscine (1-14 mg/ml) were tested on
isolated guinea pig ileum for their ability to suppress contractions induced
by a fixed concentration of pilocarpine (2 mg/ml). Determine the
percentage inhibition of pilocarpine-induced contractions by each
concentration of hyoscine, and estimate the ED50 of hyoscine under this
condition.

5. Assignment.

Contraction
(cm)
Assignment.
Wash
Pilo.
Wash
Pilo.
Hyo.
1 mg/ml
Wash
Wash
Pilo.
Hyo.
2 mg/ml
Pilo.
Hyo.
4 mg/ml
Wash
Pilo.
Hyo.
6 mg/ml
Wash
Pilo.
Hyo.
8 mg/ml
Wash
Wash
Wash
Pilo.
Pilo.
Pilo.
Hyo.
10 mg/ml
Hyo.
12 mg/ml
Hyo.
14 mg/ml

6. Assignment

Hyoscine conc (mg/ml)
% inhibition