Neuroprotective Effect of Dexmedetomidine on Hyperoxia-Induced Toxicity in the Neonatal Rat Brain
(a) Quantitative analysis of mRNA expression by real-time PCR showed a marked increase of IL-1β mRNA expression in the brain of P6 rat pups that were kept for 24 h under hyperoxia (black bar), whereas dexmedetomidine treatment restores IL-1β upon control level (hatched grey bars) depending on the dexmedetomidine concentration. Application of dexmedetomidine under room air (grey bars) showed no significant regulation on IL-1β mRNA expression. (b) The analysis of IL-1β protein expression by western blot showed a similar expression pattern. The protein expression of IL-1β is significantly increased after 24 h of hyperoxia and a single application of 5 or 10 μg/kg dexmedetomidine could restore the IL-1β protein expression almost up to control level. The densitometric data represent the ratio of the pixel intensity of the IL-1β band to the corresponding β-actin band. Blots are representative of a series of three blots. Data are normalized to levels of rat pups exposed to normoxia (CON = 100%, white bars). Bars represent mean + SEM; per group; *** versus normoxia/control; #, ##, and ### versus hyperoxia.