Modeling Neonatal Intraventricular Hemorrhage Through Intraventricular Injection of Hemoglobin

Brandon A. Miller; Shelei Pan; Peter H. Yang; Catherine Wang; Amanda L. Trout; Dakota DeFreitas; Sruthi Ramagiri; Scott D. Olson; Jennifer M. Strahle

doi:10.3791/63345

Modeling Neonatal Intraventricular Hemorrhage Through Intraventricular Injection of Hemoglobin

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Neuroscience

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JoVE Journal Neuroscience

Modeling Neonatal Intraventricular Hemorrhage Through Intraventricular Injection of Hemoglobin

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07:57 min

August 25, 2022

DOI: 10.3791/63345-v

Brandon A. Miller^1,2, Shelei Pan³, Peter H. Yang³, Catherine Wang¹, Amanda L. Trout¹, Dakota DeFreitas³, Sruthi Ramagiri³, Scott D. Olson², Jennifer M. Strahle^3,4,5

¹Department of Neurosurgery,University of Kentucky, ²Department of Pediatric Surgery,University of Texas, ³Department of Neurological Surgery,Washington University in St. Louis School of Medicine, ⁴Department of Orthopedic Surgery,Washington University in St. Louis School of Medicine, ⁵Department of Pediatrics,Washington University in St. Louis School of Medicine

Overview

This study presents a clinically relevant model for neonatal intraventricular hemorrhage (IVH) using rat pups. The introduction of hemoglobin into the ventricles mimics human pathology and allows for the evaluation of therapeutic strategies aimed at post-hemorrhagic hydrocephalus.

Key Study Components

Area of Science

Neuroscience
Neonatal brain injury
Modeling hydrocephalus

Background

Intraventricular hemorrhage (IVH) is a significant cause of neurological issues in neonates.
Current models lack the specificity to study the effects of hemoglobin and iron breakdown products.
Understanding IVH pathophysiology is critical for developing therapeutic interventions.
This study aims to fill the gap in modeling the pathology of IVH.

Purpose of Study

To develop a rat model of IVH that mimics the human condition.
To evaluate the impact of hemoglobin on ventricle size and its inflammatory effects.
To provide a platform for testing new therapies for IVH-related complications.

Methods Used

The protocol involves the stereotactic injection of hemoglobin into neonate rat ventricles.
Rat pups are anesthetized, and a 0.3 cm incision is made to access the skull for injection.
Post-injection MRI is utilized to assess brain changes over specific timeframes.
Measurements include ventricle volumes, inflammatory responses, and astrocyte activation.

Main Results

Hemoglobin injection resulted in significant ventriculomegaly and inflammatory cytokine elevation.
Astrocyte activation was notably higher in hemoglobin-injected pups compared to controls.
Differences in lateral ventricle volumes between treatment groups were observed over time.

Conclusions

This study presents a valuable model for investigating treatments for IVH and its complications.
The findings enhance understanding of IVH pathophysiology and the impact of hemoglobin.
Insights gained could lead to improved therapeutic strategies for neurological outcomes following IVH.

Frequently Asked Questions

What are the advantages of this model for studying IVH?

The model effectively mimics the human pathology of IVH, specifically the impact of hemoglobin breakdown products, making it relevant for therapeutic studies.

How is the hemoglobin injection administered?

Hemoglobin is injected into the lateral ventricles of anesthetized rat pups using a stereotactic apparatus, allowing precise delivery.

What outcomes are measured following the injection?

MRI scans are used to assess ventricular sizes, inflammatory markers, and astrocyte activation in the brain.

Can this method be adapted for other studies?

Yes, the technique allows for further investigations into CSF flow and its alterations stemming from IVH.

What are key limitations in this study?

The main limitation could be the long-term effects of hemoglobin on brain development and functionality, which needs further investigation.

What types of data can be obtained?

Data on ventricle volume changes, inflammatory responses, and astrocyte activity can be obtained through MRI and biochemical assays.

How long should monitoring after injection be conducted?

Monitoring should be conducted for at least 38 days post-injection to assess the long-term effects on ventricular size and inflammation.

We present a model of neonatal intraventricular hemorrhage using rat pups that mimics the pathology seen in humans.

This protocol is significant because we develop a clinically relevant model of IVH induced brain injury and hydrocephalus, utilizing hemoglobin injection into the ventricles, which allows for subsequent quantification of ventricle volumes in the application, to testing new therapeutic strategies. The main advantage of this technique is that it allows for the study of the pathology of IVH that is specifically mediated by hemoglobin and iron pathway blood breakdown products. This technique is also easy to use and versatile.

The implications of this technique extend towards developing therapies for post-hemorrhagic hydrocephalus, as it allows for further understanding of IVH pathophysiology and the valuation of clinically relevant treatment strategies for the prevention of neurological sequela following IVH. Demonstrating the procedure will be Sruthi Ramagiri, an Associate Post-doc from the Australia Laboratory. To begin place the anesthetized rat prone in the stereotactic apparatus with its nose positioned in the anesthesia adapter.

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