Objective To investigate the injury effects of radiation on nasal mucosa of guinea pigs in a dynamic way and the protecting effects of herbal medicines on this lesion.Methods Ninety healthy guinea pigs were randomly divided into 3 groups,i.e.blank group(I),simply radiated group(II) and treating group(III) with herbal medicines given following radiation.The animals of groups II and III were given radiation at a dosage of 5 Gy,one time a week and lasted for 3 weeks by a linear accelerator at 6 MeV.Then,animals in group III were fed with modified Baihegujing Decoction for different periods according to a sub-grouping schedule and those in group I and II were kept normal feeding for the same periods as that for group III.All these animals were killed at the scheduled different periods,1 d,1,2,4,10 weeks and half one year respectively,and tissue samples were taken from the anterior end of inferior turbinate for light and electronic microscopy plus image analysis,MDA and SOD determination.Results Compared with that of group I,animals in group II showed acute inflammatory reaction in nasal mucosa at very early stage following radiation,much aggravated in the lesion at the phase of second week,with only a small part of cili remained on the nasal epithelia with normal structure,and the lesion began to recover at the time point of fourth week,lasted to that point of 6 month,in an in-complement way and with squamous epithelia transformation.
In contrast,those in group III showed much relieved inflammatory changes and very earlier recovering process in the mucosa,with large area of epithelia keeping normal ciliary epithelia structure.Mean while,SOD activity was decreased and MDA level was elevated among all animals in groups II and III,but the recovering period was much shorter in the animals of group III than in group II,with these levels recovered to normal within 4 weeks.Conclusions Modified Baihegujing Decoction can accelerate the recovering process of nasal mucosa injury following radiation through accelerating the eliminating effects on oxygen-derived free radicals and elevating the activity of SOD to reduce the early inflammatory reaction largely.