All
  • All
  • Insight
  • Research Services
  • Preclinical CRO
  • Animal Resource Bank
CN
中文 English

Animal model of cerebral hemorrhage

Animal model of cerebral hemorrhage

Explore more

Hemorrhagic stroke
Psychiatric & neurological disease models

On this page

Model Introduction

Model Introduction

Platform Service Advantages

Platform Service Advantages

Experimental results

Experimental results

Publish an article

View more

Hemorrhagic stroke

Introduction to Animal Models of Cerebral Hemorrhage

Animal models of intracerebral hemorrhage are experimental systems that mimic intraparenchymal bleeding and its secondary brain injury through surgical or chemical techniques. Common methods include collagenase injection and autologous blood injection. The collagenase method induces sustained hemorrhage by locally injecting an enzyme that disrupts the vascular basement membrane, whereas the autologous blood method involves directly infusing a defined volume of blood into the brain parenchyma to form a hematoma. Following model establishment, hallmark pathological changes such as hematoma formation, cerebral edema, blood–brain barrier disruption, and neuroinflammatory responses can be observed, accompanied by motor deficits and neurological impairment. These models are widely employed in studies of the pathogenesis of intracerebral hemorrhage and in the evaluation of neuroprotective agents.

Service Advantages of the Aniphe Biolaboratory Cerebral Hemorrhage Animal Model Platform

Aniphe Biolaboratory animal model platform for cerebral hemorrhage centers on the stable establishment of hemorrhagic lesions and the reproducible simulation of secondary brain injury, providing a reliable in vivo experimental system for studying the pathogenic mechanisms of intracerebral hemorrhage and evaluating neuroprotective therapeutics.

Comprehensive model coverage

Multiple modeling approaches are well-established.

It encompasses mainstream cerebral hemorrhage models, such as collagenase injection and autologous blood injection, and is adaptable to diverse research requirements.
Standardization of the modeling process

The hemorrhagic focus is highly controllable.

The extent and severity of hemorrhage can be precisely modulated by adjusting the enzyme concentration or the injection volume, enabling graded modeling.
Multidimensional Evaluation System

The model exhibits high stability and repeatability.

Standardized positioning and operational procedures reduce bleeding variability and inter‑individual differences, thereby enhancing data consistency.
Adapted for multi-cycle studies

Pathological features closely resemble clinical findings.

It can reliably reproduce the typical pathological changes of cerebral hemorrhage, including hematoma formation, cerebral edema, inflammatory responses, and neuronal injury.
Standardization of Data Delivery

Supports multi‑time‑window studies

It covers the acute, subacute, and recovery phases, and is suitable for dynamic interventions and mechanistic studies.
Standardization of Data Delivery

The multi-dimensional evaluation system has been refined.

Systematic pharmacological efficacy validation is achieved through a combination of behavioral assessments, imaging analyses, and histopathological examinations.
Modeling cycle

24–32 weeks

1  Laboratory animals

SD male rats

1  Positive drug

Osteopontin (OPN)

1  Application areas

It is primarily used to model intracerebral hemorrhage and its secondary injury processes, with broad applications in studying pathogenic mechanisms and developing therapeutics. It enables the analysis of pathological changes such as hematoma formation, cerebral edema, inflammatory responses, and neuronal damage, and is employed for in vivo efficacy evaluation of neuroprotective and functional‑recovery–related drugs, making it an essential tool for basic and translational research on cerebrovascular diseases.

Experimental results

Construction of an Animal Model of Cerebral Hemorrhage

01 Collagenase Injection Method: This study established STAT1‑overexpressing and intracerebral hemorrhage (ICH)–related models in SD rats, with experimental groups receiving either high‑glucose treatment or intranasal administration of OPN. STAT1 overexpression was achieved via tail‑vein injection of AAV‑STAT1; 21 days later, an ICH model was induced by stereotactic collagenase injection. Concurrently, 3 hours after ICH induction, a 50% glucose solution was administered intraperitoneally to establish a hyperglycemic state, thereby mimicking the conditions of cerebral hemorrhage combined with hyperglycemia. Additionally, OPN was delivered intranasally 1 hour after ICH modeling, with alternating drops into both nasal cavities to facilitate central delivery, in order to evaluate its protective effects against ICH‑induced brain injury.

02 Autologous blood injection into the basal ganglia region: A cerebral hemorrhage model was established by injecting autologous blood. SD rats were anesthetized with isoflurane and fixed in a stereotactic apparatus. A burr hole was drilled at the right basal ganglia (1 mm posterior to Bregma, 3 mm lateral to the sagittal suture, at a depth of 6 mm). Autologous blood was collected via the lateral tail vein and slowly infused in aliquots at a rate of 2 μL/min, totaling 50 μL. After injection, the needle was left in place for a specified period to minimize reflux, followed by gradual withdrawal of the needle and closure of the scalp incision. In the sham‑operation group, only the craniotomy and stereotactic positioning were performed; no blood was injected.

Photo of the modeling node

 

 

Neurological function score

Behavioral scoring (Garcia test) was performed at 72 hours post-ICH. Neurological function scores revealed a significant decline compared with the sham-operated group. OPN ameliorated ICH‑induced neurological deficits; however, overexpression of STAT1 reversed OPN’s beneficial effects on neurological function when compared with the OPN‑treated group.

 

 

Blood glucose testing

Twenty-four hours after OPN treatment, blood glucose levels were measured using a glucometer; no significant differences in blood glucose were observed among the groups, indicating that rOPN had no effect on blood glucose levels.

 

 

Imaging examination

Transmission electron microscopy was used to examine the ultrastructure of the perihematoma region and the microvascular architecture in the injury zone. Results from transmission electron microscopy showed that, compared with the sham‑operated group, both the ICH+HG group and the empty‑vector control group (IHC+HC+AAV‑NC) exhibited significant mitochondrial structural damage, characterized by loss of mitochondrial cristae, mitochondrial swelling, and vesicular dilation, accompanied by the formation of autophagosomes and autolysosomes; the endothelial cell layer was uneven in thickness, and tight junctions were absent. In the AAV‑STAT1 overexpression intervention group, these pathological changes were further exacerbated, with markedly enhanced autophagic activity. In the ICH group, mitochondrial swelling and vacuolization were less pronounced. Following OPN treatment, mitochondrial damage was alleviated to varying degrees, as evidenced by partial restoration of mitochondrial cristae and reduced vesicular dilation, along with a tendency toward more tightly organized intercellular junctions in the endothelial cells.

 

 

Brain Tissue Water Content Measurement

Four regions—bilateral basal ganglia and bilateral cortex—were sampled, with the cerebellum serving as an internal control; dry and wet weights were determined using an electronic balance.

 

 

Evans blue assessment of blood–brain barrier integrity

Compared with sham-operated animals, the ICH+HG group exhibited an increased brain tissue permeability, whereas the OPN‑treated group showed a significant reduction in brain tissue permeability. In contrast to the OPN‑treated group, brain tissue permeability was markedly elevated following OPN treatment and STAT1 overexpression.

WB results showed that, compared with the sham‑operated group, 72 hours after ICH surgery, the brain tissue exhibited significantly reduced expression levels of ARG1, BDNF, CD206, TKB‑1, and p‑TKB1, while the expression levels of MHC‑II, iNOS, CD86, and STAT1 were significantly increased. Following OPN treatment, the expression levels of ARG1, BDNF, CD206, TKB‑1, and p‑TKB1 were markedly elevated, whereas no significant changes were observed in the expression levels of MHC‑II, iNOS, CD86, or STAT1. Moreover, overexpression of STAT1 was able to reverse OPN‑induced increases in the expression levels of ARG1, BDNF, CD206, and p‑TKB1.

 

 

HE test results

HE staining revealed that, compared with the sham‑operated group, both the ICH+HG group and the empty‑vector control IHC+HC+AAV‑NC group exhibited marked pathological damage: diffuse hemorrhagic foci were observed within the brain parenchyma, accompanied by widening of perivascular spaces; microvascular endothelial cells showed swelling and detachment, and extensive infiltration of neutrophils and monocytes was evident in areas of erythrocyte extravasation. Neuronal arrangement was disorganized, with some nuclei showing pyknosis or lysis. In the AAV‑STAT1 overexpression intervention group, pathological injury was further exacerbated, with an expanded hemorrhagic zone and a larger area of nuclear structural blurring. The ICH group displayed smaller hemorrhagic areas and less extensive nuclear blurring than the ICH+HG group, the empty‑vector control, and the AAV‑STAT1 overexpression group. By contrast, the OPN‑treated group demonstrated a pronounced protective effect, characterized by reduced hemorrhagic size, attenuated perivascular edema, decreased density of inflammatory cell infiltration, and improved clarity of neuronal nuclear morphology. These findings suggest that STAT1 overexpression may amplify the inflammatory cascade underlying hemorrhagic injury, whereas OPN exerts neuroprotective effects by suppressing inflammatory infiltration and cellular degeneration.

 

 

 

 

Gene expression analysis

The expression levels of MHC-II, iNOS, CD86, Arg-1, CD206, and STAT1 proteins in the brain tissues of rats from each group were assessed.

 

 

 

 

ELISA assay

The secretion levels of pro-inflammatory cytokines such as TNF-α, IL‑1β, and IL‑12, as well as anti-inflammatory cytokines including IL‑4, IL‑10, IL‑13, and TGF‑β, were measured in the brain tissues of rats across the experimental groups. ELISA results showed that, compared with the sham‑operated group, 72 hours after ICH, the brain tissue exhibited significantly elevated expression of the pro-inflammatory cytokines IL‑1β, IL‑12, and TNF‑α, while the expression of the anti-inflammatory cytokines IL‑13, IL‑10, IL‑4, and TGF‑β was markedly reduced. Following OPN treatment, the levels of IL‑1β, IL‑12, and TNF‑α were significantly decreased, whereas the levels of IL‑13, IL‑10, IL‑4, and TGF‑β were significantly increased. Moreover, STAT1 was able to reverse OPN’s inhibitory effect on the expression of IL‑1β, IL‑12, and TNF‑α, while preserving its enhancing effect on the expression of IL‑13, IL‑10, IL‑4, and TGF‑β.