[Effect of radiation on nasal mucosa and the microvascular casting of guinea pig].
OBJECTIVE
To study the histopathologic and microvascular changes in nasal mucosa of guinea pigs following a series of irradiation.


METHODS
A total of 84 healthy guinea pig were divided into two groups randomly: the irradiation group (n=72) and the control group (n=12). The animals of the irradiation group were exposed nasally to linear accelerator X-rays at 5.0 Gy once a week for three weeks. At 0.5, 1, 2, 3, 5, 6 month after X-irradiation 12 animals from each group were sacrificed at each time point. The animals of control group did not be irradiated and were sacrificed after 6 month. Their middle nasal turbinate mucosa of 6 animals from each group was observed under optical microscope and scanning electron microscope and the another 6 animals was made microvascular corrosion casts.


RESULTS
In the irradiation group, the early histopathological transformation was acute inflammatory reaction, nasal mucosa tissues congesting, partial nasal mucosa necrosis or shedding. The inflammation cells infiltrated into the submucosa. The acute inflammatory reaction declined as the time went by. Then the nasal mucosa repaired step by step. But parts of the area were squamous epithelium instead of the normal ciliary structure. Through scanning electron microscope, we found the capillary of nasal mucosa expanded and congested, the vascular endothelial cell swelled. As the time went by, the capillary became deformation and tore and the microvascular networks broke off. All changes which led to capillary density descended. Although partial area had new capillary, but the structure was disordered and had no microcirculation function.


CONCLUSIONS
The nasal mucosa injury, the squamous metaplasia and the microvascular networks broke off can form a pathological basis of dysfunction after irradiation.
Liu
Yuehui
Y
Department of Otorhinolaryngology, the Second Affiliated Hospital of Nanchang University, Nanchang, 330006, China. liuyuehuiclark@21CN.com
Qiu
Lubin
L
Li
Cheying
C
D000818:Animals; D006168:Guinea Pigs; D008833:Microcirculation; D009297:Nasal Mucosa / Q000098:blood supply / Q000473:pathology / Q000528:radiation effects*; D011833:Radiation Injuries, Experimental; D014965:X-Rays / Q000009:adverse effects*