Experimental bronchial length tensiometry

Summary

Measurement of bronchial long tension allows analysis of the actual effect of drugs that have a dilating or constricting function on the trachea.

Operation method

Experimental bronchial length tensiometry

Materials and Instruments

Equipment: surgical tools, small vessel wire muscle tracer.
Reagents:
① Krebs physiological salt solution (118.07 mmol/L NaCl, 4.69 mmol/L KCl, 2.52 mmol/L CaCl2, 1.16 mmol/L MgSO4, 1.01 mmol/L NaH
2
PO
4
2.01 mmol/L NaH 2 PO 4 , 25 mmol/L NaHCO
3
and 11.10 mmol/L glucose).
② Krebs physiological salt solution (63.39 mmol/L NaCl, 60 mmol/L KCl, 2.52 mmol/L CaCl
2
2.52 mmol/L CaCl2, 1.16 mmol/L MgSO
4
1.16 mmol/L MgSO 4, 1.01 mmol/L NaH
2
PO
4
2 PO 4, 25 mmol/L NaHCO
3
, 11.10 mmol/L glucose).
(iii) Tribromoethanol (avertin).

Move

The basic procedure for the bronchial length tensiometry experiment can be divided into the following steps:
A Adult mice are anesthetized with an intraperitoneal injection of tribromoethanol (avertin) at 240 mg/kg.
B The thoracic cavity of the mice is opened, and the entire lungs, together with the main trachea, are carefully removed and placed into the pre-prepared Krebs' physiological saline solution.
C Other tissues surrounding the main trachea and the main bronchus are carefully removed under the fluoroscope.
D The isolated left main bronchus (only one lobe on the left side) was carefully cut along the bifurcated end and the entry end and trimmed to form a 2-mm bronchial ring (the entry end was retained and the bifurcated end was trimmed).
E 5 mm of bronchial ring was added to a small-vessel wire myograph in the small-vessel wire myograph chamber of the Danish Myo Technology (DMT). E 5 mm of small-vessel wire myograph was added to the small-vessel wire myograph chamber of the Danish Myo Technology (DMT). E In the small-vessel wire myograph chamber of the Danish Myo Technology (DMT), 5 ml of Krebs' physiological salt solution preheated to 37 °C was added and the cut bronchial rings were hung in the chamber with 0.4 mm diameter steel
wire (taking care that the wire was attached to the muscle and not to the cartilage rings).
F The bath was connected to the main body of the myograph, and a gas mixture of 5% CO2 and 95% O2 was introduced. A temperature sensor was inserted, the temperature was set at 37 °C, and recording was started on a computer using the Chart software.
G The tracheal ring was equilibrated in the unstretched state for approximately 10 minutes, and then the tracheal base tension was given and adjusted several times to equalize the base tension at approximately 5 mN, and was equilibrated for approximately 40 minutes.
H The tracheal ring was pre-stimulated before the experiments with 5 ml of Krebs' liquid containing 60 mmol/L KCl, and approximately 40 minutes were allowed for the tracheal ring to be pre-stimulated. Pre-stimulate the tracheal ring with 5 ml of Krebs' solution containing 60 mmol/L KCl before the experiment, and wash off the KCI with Krebs' solution after about 5 minutes of contraction.
I Start the experiment, either by stimulating with Krebs' solution containing different concentrations of KCl to measure depolarization-induced tracheal contraction, or by stimulating the trachea with different agonists (e.g., MCh) in a gradient to measure the effect of the agonists on the contraction of the trachea, or by analyzing the diastolic effect of the diastolytic agent after the agonist-induced contraction. The results of the assay are shown in Figure 8-4-6.

For more product details, please visit Aladdin Scientific website.

https://www.aladdinsci.com/