Real-Time Detection of Ferulic Acid Effects on Rat Left Ventricle Using Pressure-Volume Conductivity Catheter

Summary

This protocol describes a method for measuring left ventricular pressure and volume using the pressure-volume conductance technique. This method enables continuous real-time monitoring of the effects of drugs on the heart.

Abstract

Decreased cardiac function can have a negative impact on other organs. The left ventricular pressure-volume relationship is considered to be a valid method for evaluating cardiac function. Real-time monitoring of cardiac function is important for drug evaluation. Under closed-chest conditions, the miniature transducer, which is an important component of the pressure-volume catheter, enters the left ventricle of the rat through the right carotid artery. The device visualizes the changes in cardiac function during the experiment in the form of a pressure-volume loop. The actual volume of the ventricle is calculated by altering the conductivity of the blood by injecting 50 µL of a 20% sodium chloride solution into the rat's left jugular vein. The actual volume of the rat's ventricular cavity is calculated by measuring the conductivity of the blood in a known volume using a pressure-volume conductance catheter. This protocol allows for continuous observation of the effects of drugs on the heart and will promote the rationale for the use of specialty ethnic drugs in cardiovascular disease.

Introduction

Cardiovascular disease has the highest mortality rate in the world¹. Its causes include coronary artery stenosis (myocardial ischemia), coronary artery blockage (myocardial infarction), and ischemia-reperfusion injury². As the heart is in a constant systolic and diastolic cycle, it is one of the most energy-demanding parts of the body. Therefore, when the coronary arteries have difficulty maintaining sufficient energy and oxygen, cardiac function inevitably decreases, which has a negative impact on other organs^3,4. The heart is a powerhouse in the circulatory sys....

Protocol

The animal protocol was reviewed and approved by the Chengdu University of Traditional Chinese Medicine Experimental Animal Welfare Ethics Committee (Record No. 2023-04). Male Sprague Dawley (SD) rats (280 ± 20 g, 8-10 weeks old) were used for the present study. The rats were kept in an animal chamber and were free to drink and eat.

1. Solution preparation

1. Prepare 0.9% NaCl solution to be used to keep the work area adequately moist.
2. To prepare 20% hy.......

Discussion

It is essential to adopt a rational dosing strategy for different states of cardiac function. The pressure-volume conductance catheter technique is the most intuitive way to study left ventricular function⁵. This method enables the effects of drugs on cardiac function to be studied from a whole perspective. We describe the various stages of the experiment in detail. This will provide some facility for the study of heart function.

The pressure volume conductivity cathete.......

Materials

Name	Company	Catalog Number	Comments
1 mL syringe	Sartorius AG, Germany	-
Animal temperature maintainer	Rayward Life Technology Co., Ltd	69020
Dual Bio Amp	Millar, Inc., USA	DA-100
Enzyme-Active Powdered Detergent	Alconox Inc., USA	1104
Ferulic acid	Macklin Biochemical Co., Ltd,Shanghai, China	F900027
Mikro-Tip Catheter Transducers, SPR-838NR	Millar, Inc., USA	SPR-838NR
Millar Miro-Tip Pressure Volume (MPVS) Ultra	Millar, Inc., USA	SPR-869
Pet electric clippers	Jinyun County New Concept Home Supplies Co., Ltd.	-
Power Lab 8 / 35	Millar, Inc., USA	PL3508
Sodium Chloride, NaCl	Kelong Chemical Reagent, Chengdu, China	KX829463
Veet hair removal cream	Shanghai Songqi E-commerce Co., Ltd.	3226470