In contrast, Δ9THC, a non-selective cannabinoid receptor (CB1 and CB2) agonist administered intraperitoneally significantly alters vagal balance, stabilizes respiratory pattern, and produces a dose-dependent reduction in sleep related respiratory event density in an established rat model of sleep-disordered breathing (Carley et al., 2002). The gene discussed is CNR1; the disease is sleep apnea syndrome.