Table 2.

The characteristics of the included basic science studies.

References	Models	Time course	Treatments	Outcomes
Soukhova-O'Hare et al. (42)	CIH mice	5 or 24 weeks	Tadalafil	Sexual activity was suppressed after CIH. Decreased expression of endothelial NOS after CIH. Tadalafil treatment significantly improved erectile function.
Liu et al. (43)	LTIH rats	6 weeks	Apocynin	LTIH markedly attenuated the erectile responses, and these effects were partially prevented by apocynin treatment
Zhu et al. (44)	CIH rats	5 weeks	N-acetylcysteine (NAC)	Administration of NAC before CIH significantly improved CIH-induced impaired erectile function
Liang et al. (45)	CIH rats	8 weeks	miR-301a-3p-enriched exosome	miR-301a-3p-enriched exosome treatment significantly recovered erectile function

CIH, Chronic intermittent hypoxia; LTIH, Long-term intermittent hypoxia.