Cathartic Effect of Magnesium Sulfate

Cathartic Effect of Magnesium Sulfate

• Purpose: Observe the cathartic effect of magnesium sulfate and its mechanism.
• Mechanism: Oral magnesium sulfate produces magnesium and sulfate ions. These ions increase osmotic pressure in the intestine. This increased pressure inhibits water absorption, enlarging the intestinal lumen. The increased volume triggers intestinal peristalsis, resulting in a cathartic effect.
• Observation Content:
  • Advance percentage of carmine: Calculated as (distance carmine moved in the bowel / total intestinal length) x 100%.
  • Fecal form and features: Observations include solid/shape, sparse/shapeless.
• Materials: Mice, carmine solution, syringe, scissors, electronic balance, and carmine-magnesium sulfate solution.
• Experimental Procedure:
  • Step 1: Select and weigh two mice per group, labeling them (A and B) with picric acid.
  • Step 2: Administer treatments. Group A receives 0.8ml carmine-saline solution orally. Group B receives 0.8ml carmine-magnesium sulfate solution orally.
  • Step 3: Record data and analyze the cathartic effect. Data includes the advance percentage of carmine, and fecal traits.

Intragastric Administration Method

• Mice are fed via intragastric gavage.
• A gastric lavage with a ball-tipped feeding needle is used during feeding.
• The feeding needle is directed into the stomach going through the pharynx and esophagus, along the oral palate.

Observation After Drug Treatment (30 Minutes)

• Mice are killed using cervical dislocation.
• The abdomen is cut open with small scissors, exposing the internal organs.
• Observe peristalsis and intestinal expansion.
• The mesentery is stripped, and the intestine is pulled out.
• Measure the distance from the pylorus to the leading edge of carmine (I) and the distance from the pylorus to the terminal rectum (L).
• Calculate advance percentage of carmine as I/L * 100%.

This quiz explores the cathartic effect of magnesium sulfate, focusing on its mechanism and the observations related to intestinal peristalsis. It covers the experimental procedure, including the use of mice and carmine solution. Test your knowledge on the principles and outcomes of this interesting experimental study.