# Homeostatic and endocrine responses as the basis for systemic therapy with medical gases: ozone, xenon and molecular hydrogen.
> 医療ガス（オゾン・キセノン・分子状水素）の恒常性維持および内分泌応答に基づく全身作用の比較検討


## Abstract

This review compares the physiological activities of three medical gases—ozone (O₃), xenon (Xe), and molecular hydrogen (H₂)—representing oxidizing, inert, and reducing agents, respectively. Analysis of published and original data indicates that all three gases can influence the neuroendocrine system by modulating hormone production or secretion through the hypothalamic-pituitary-adrenal, hypothalamic-pituitary-thyroid, and hypothalamic-pituitary-gonadal axes, as well as via gastrointestinal pathways. Repeated administration over time leads to the establishment of conditioned homeostatic reflexes, rendering the physiological modulations predictable and stable. The review frames these phenomena within a Pavlovian conditioned-reflex model, suggesting that anticipatory adaptive responses underlie the systemic effects observed with repeated gas exposure.

### Mechanism

Medical gases including H₂ modulate hormone secretion via hypothalamic-pituitary axes (adrenal, thyroid, gonadal) and gastrointestinal pathways; repeated administration establishes conditioned homeostatic reflexes that stabilize physiological regulation.

## Bibliographic

- **Authors**: Nazarov EI, Khlusov IA, Noda M
- **Journal**: Med Gas Res
- **Year**: 2021
- **PMID**: [34213500](https://pubmed.ncbi.nlm.nih.gov/34213500/)
- **DOI**: [10.4103/2045-9912.318863](https://doi.org/10.4103/2045-9912.318863)
- **PMC**: [PMC8374457](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8374457/)
- **Study type**: review
- **Delivery route**: mixed routes
- **Effect reported**: not assessed

## Delivery context

This study combines multiple delivery routes. As a general principle, the most efficient route for routine hydrogen intake is inhalation. Inhalation carries explosion risk (empirical LFL of 10%; high-concentration devices are documented in the Consumer Affairs Agency accident database and are not recommended).

## Safety notes

This study combines multiple delivery routes. As a general principle, the most efficient route for routine hydrogen intake is inhalation. Inhalation carries explosion risk (empirical LFL of 10%; high-concentration devices are documented in the Consumer Affairs Agency accident database and are not recommended).

See also:
- [Inhalation concentration and LFL / UFL](https://h2-papers.org/en/safety-notes/inhalation-concentration)
- [Consumer Affairs Agency accident cases](https://h2-papers.org/en/safety-notes/accident-cases)
- [Inhalation safety threshold lineage](https://h2-papers.org/en/safety-notes/lineage)

---

> **Cite as**: H2 Papers — PMID 34213500. https://h2-papers.org/en/papers/34213500
> **Source**: PubMed PMID [34213500](https://pubmed.ncbi.nlm.nih.gov/34213500/)