# Neural Gene Expression in Sleep Deprivation and Recovery

> **NIH NIH R01** · SRI INTERNATIONAL · 2022 · $888,581

## Abstract

PROJECT SUMMARY
 Although slow wave activity (SWA) in the EEG has been linked to homeostatic sleep regulation,
the neurobiological substrate of sleep homeostasis is little understood. In three different species, we
have identified a rare population of cortical GABAergic interneurons that expresses c-FOS only during
sleep. These sleep-active cells express the enzyme neuronal nitric oxide synthase (nNOS) and
NK1R, the receptor for Substance P. Cortical nNOS/NK1R neurons seem to monitor the homeostatic
sleep drive that accumulates during wakefulness because the percentage of nNOS/NK1R cells that
express cFOS during sleep is proportional to prior wake duration. Cortical nNOS/NK1R cells are
exceptional among cortical GABAergic neurons in that they have widespread intracortical projections.
We have proposed that cortical nNOS/NK1R neurons are critical for orchestrating EEG SWA during
sleep through release of an amino acid transmitter (GABA), a peptidergic transmitter (Neuropeptide
Y), and/or a gaseous transmitter (NO). Thus, cortical nNOS/NK1R neurons may be part of the long-
sought neuroanatomical circuit underlying the sleep-dependent “Process S” and may provide insight
into the neural circuitry underlying homeostatic sleep regulation. Determination of the inputs to
cortical nNOS/NK1R neurons will be central to understanding their regulation and function. In the
present application, we will test the hypotheses that Substance P excites cortical nNOS neurons
through NK1R and that cortical nNOS/NK1R neurons are both sufficient and necessary for
propagation of EEG SWA. To address these hypotheses, we will use a combination of in vitro
physiology, cellular pharmacology, functional neuroanatomy, microendoscopic Ca2+ imaging,
optogenetic stimulation and inhibition in vitro and in vivo, and cell-specific ablation using both wildtype
and multiple transgenic mouse strains. Together, these experiments will provide further insight into
the afferent regulation of cortical nNOS/NK1R neurons, as well as the necessity and sufficiency of
these cells for EEG SWA. The results will not only enhance our understanding of sleep/wake
regulation, but may also have implications for understanding sleep disorders and neurological and
psychiatric diseases involving the cerebral cortex.

## Key facts

- **NIH application ID:** 10323666
- **Project number:** 5R01HL059658-18
- **Recipient organization:** SRI INTERNATIONAL
- **Principal Investigator:** Thomas S Kilduff
- **Activity code:** R01 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2022
- **Award amount:** $888,581
- **Award type:** 5
- **Project period:** 1997-09-30 → 2023-12-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10323666

## Citation

> US National Institutes of Health, RePORTER application 10323666, Neural Gene Expression in Sleep Deprivation and Recovery (5R01HL059658-18). Retrieved via AI Analytics 2026-05-23 from https://api.ai-analytics.org/grant/nih/10323666. Licensed CC0.

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