 Metaplasticity occurs when the LTF is itself plastic or variable.Intermittent hypoxia-induced LTF has also been demonstrated in carotid denervated rats, suggesting that synaptic plasticity due to intermittent hypoxia also works through other mechanisms outside of carotid chemoafferents.Aside from this, intermittent hypoxia also alters overall nitric oxide production, concentration, and gene expression, which occurs due to cardiovascular adaptations to hypoxia.