# Targeting vascular contractile cells in capillary stasis after cardiac arrest

> **NIH NIH R21** · UNIVERSITY OF PITTSBURGH AT PITTSBURGH · 2022 · $197,969

## Abstract

ABSTRACT
There are more than 500,000 cases of cardiac arrest in the US annually. While timely resuscitation is often
effective at restoring cardiac function, many survivors develop brain injury. After resuscitation from cardiac
arrest, cerebral microvascular disturbances produce a secondary neuronal injury that worsens neurological
outcome. We have recently uncovered important cortical microvascular alterations in a clinically relevant model
of asphyxial cardiac arrest: multifocal capillary stasis in cortical capillaries and arteriolar vasoconstriction.
Preliminary data also suggest that pericytes and smooth muscle cells contribute to capillary stasis. Moreover, a
microvascular-targeted strategy partially improved cortical perfusion and neurological outcome in our model.
To fully elucidate the role of vascular contractile cells in capillary stasis and neurological outcome, we propose
to use a highly specific chemogenetic approach in a model of asphyxial cardiac arrest in mice. Using viral
transduction, we will induce the expression of inhibitory Designer Receptors Exclusively Activated by Designer
Drugs (DREADD) in pericytes in PDGFRβ-CreER mice, and in both pericytes and smooth muscle cells in NG2-
CreER mice. Activation of inhibitory DREADDs will induce relaxation of pericytes and smooth muscle cells after
cardiac arrest. Aim 1 will define the full scope of the effect of pericyte and smooth muscle cells relaxation on
cardiac arrest-induced capillary stasis in mice expressing the inhibitory hM4Di chemogenetic receptor. The
inhibitory DREADD AAV-EF1a-DIO-hM4D(Gi)-mCherry will be injected in the motor cortex of PDGFRβ-CreER
and NG2-CreER mice. We will assess the isolated effect of pericyte relaxation and the combined effect of
pericyte and arteriolar smooth muscle cells relaxation on capillary perfusion. Aim 2 will determine if inducing
relaxation of pericytes post-cardiac arrest improves neurological and histological outcomes. For this aim, we
will express the inhibitory DREADD hM4Di in all pericytes by breeding PDGFRβ mice with R26-LSL-
hM4Di/mCitrine mice. We will induce cerebral and then global pericyte relaxation after cardiac arrest and
assess neurological and histological outcomes.
Through this novel and specific approach, we will characterize the role of pericytes and smooth muscle cells in
mediating microvascular stasis after cardiac arrest. If successful in improving neurological outcome, this
microvascular targeted strategy could lead to a novel therapeutic opportunity to prevent secondary brain injury.

## Key facts

- **NIH application ID:** 10376256
- **Project number:** 5R21NS121501-02
- **Recipient organization:** UNIVERSITY OF PITTSBURGH AT PITTSBURGH
- **Principal Investigator:** Mioara D. Manole
- **Activity code:** R21 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2022
- **Award amount:** $197,969
- **Award type:** 5
- **Project period:** 2021-04-01 → 2024-03-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10376256

## Citation

> US National Institutes of Health, RePORTER application 10376256, Targeting vascular contractile cells in capillary stasis after cardiac arrest (5R21NS121501-02). Retrieved via AI Analytics 2026-05-25 from https://api.ai-analytics.org/grant/nih/10376256. Licensed CC0.

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