By
Sina Walker

Scientific Writer

Lessons from the Langendorff

Do you need help with Langendorff technique?

Here are some essential pro tips and practical advice from isolated heart expert Dr. Melanie White (University of Sydney) for Langendorff heart and perfusion.

Watch the full webinar >>
More Langendorff tips in our Knowledge Base >>

Lessons from the Langendorff: Heart

1. The condition of the animal will influence the function of the heart

If your animal is stressed in any way this is likely to influence the function of the heart. Likewise, if the animal is diseased in any way this will also influence the function of the heart.

Pro Tip: If your heart is not performing at the end of baseline, you should take a closer look at the cadaver. There might be some sort of indicator that the animal had an issue that wasn't otherwise detectable until you performed the surgical procedure.

2. Heparin is important

Heparin is incredibly important, especially in small rodent models. That's because any kind of blood clot is akin to an ischemic insult.

3. Contractility is maintained when the heart is submerged

We find better contractility is maintained throughout a perfusion protocol when the heart is submerged in a warm buffer, be it crystalloid or any additional buffers that you may choose.

4. Ensure you can see the end of the cannula through the aorta

We find that it is important that you can see the end of the cannula.

Pro Tip: You should be able to gently touch the heart and can see the cannula through the aorta. If you can't see the end of the cannula it might indicate that it has perforated through the aortic valve and that is going to influence your system.

5. Homemade balloons are tricky but worth the effort!

We use homemade balloons. They are tricky! But because you can change the size, it is well worth the effort.

Pro Tip: What is the best material to use to make a homemade balloon? The heart size and pathology being studied are important factors when selecting the material to use since each material has both advantages and disadvantages. Ideally, the wall tension balloon should remain constant and not contribute significantly to the measurement, while the volume should uniformly expand. Additionally, the ability to see through will assist in ensuring that there are no air bubbles in the balloon.

6. Practice, practice, practice

Practice is key! Langendorff is not an easy technique. Mastery comes with time. So practice, practice, practice!

Lessons from the Langendorff: Perfusion

7. Keep dedicated glassware

Don't swap glassware and don't use glassware for multiple purposes. If the glassware is for a buffer, it should only be used for that single buffer.

8. Water source is important!

Your choice of water source is incredibly important. If your hearts aren't making it through baseline, try checking or changing your water source.

9. Everything needs to be filtered repeatedly

Everything needs to be filtered, and it needs to be filtered repeatedly, especially if you are using a small rodent model. Even small particulates are akin to an ischemic insult.

10. Air bubbles are akin to inducing an ischemic insult

The same can be said for air bubbles - they can cause an ischemic insult. For that reason, we use an inline air bubble trap.

11. Ensure appropriate cleaning protocols

We also want to ensure appropriate cleaning protocols for everything! If there is any kind of bacteria or mold, that could lead to cardio-toxic effects.

Pro Tip: Clean your air stones!

12. Release tubing from the peristaltic pump when not in use

To ensure you maintain your flow rates for as long as possible over many experiments, it is important to release the tubing from the peristaltic pump. Keeping it attached adds additional pressure when not in use.

Our Solutions

We offer a range of solutions for both constant flow and constant perfusion pressure Langendorff setups. Our Radnoti Langendorff Foundation Systems can be customized for either constant pressure or flow for perfusing both mice and rat hearts. These systems center around apparatuses that are made from high-quality, crystalline glassware and include PowerLab data acquisition hardware, LabChart data analysis software. Further tailored cardiac measurements can be made by additionally purchasing from a range of compatible isolated heart kits and accessories. See here for more information about our Radnoti Langendorff Systems.

Our PowerLab C Rodent Langendorff Foundation System is also a great option for those who are wanting a high-quality, modular, yet compact Langendorff apparatus, which provides flexibility for configuring various isolated rodent heart experimental solutions. The STH Pump Controller uses the perfusion pressure to control the Peristaltic Pump’s speed, allowing the system to operate easily in constant perfusion pressure or perfusion flow. Additionally, the system is also supplied with LabChart Lightning software, flexible PowerLab C data acquisition, and hardware for measuring perfusion pressure and temperature. See here for a brief overview of the PowerLab C Rodent Langendorff Foundation System and its components.

Our PowerLab C Rodent Langendorff Foundation System.

An introduction to the isolated Langendorff heart technique (free on-demand webinar)

Best practices and key considerations when for setting-up an isolated Langendorff heart preparation

Langendorff technique webinar with Dr Melanie White

Dr. Melanie White

ARC DECRA Research Fellow
School of Medicine
University of Sydney

About the speaker...

Dr. Melanie White is a member of the Charles Perkins Society, a Heart Foundation Future Leader Fellow and teaches senior students in the discipline of Pathology at the University of Sydney School of Medicine.

Her research interests include understanding more about how cells adapt to their changing environment by altering proteins using post-translational modifications. Her team’s work centers on asking these questions in clinically relevant models of myocardial ischemia (heart attack), type 2 diabetes and obesity.

For more information about isolated heart studies and the equipment required, check out our wide range of systems available for Langendorff and Working Heart preparations.

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22 November, 2019