R. Nagler et al., SIALOCHEMICAL PROFILE OF X-IRRADIATED MAJOR SALIVARY-GLANDS IN THE RAT, International journal of radiation biology, 71(4), 1997, pp. 441-448
Citations number
41
Categorie Soggetti
Radiology,Nuclear Medicine & Medical Imaging","Nuclear Sciences & Tecnology
The purpose of this study was to examine various sialochemical paramet
ers in parotid (P) and submandibular (SM) secreted saliva of irradiate
d rats. Various doses of radiation from 2.5 to 15 Cy were administered
to the head and neck region and the saliva was evaluated for its amyl
ase activity and the concentration of sodium (Na), potassium (K) and t
otal protein. Saliva samples containing equal amounts of proteins were
also electrophoresed on separatory SDS gels, silver-stained and exami
ned for possible qualitative alterations. The total protein concentrat
ions of P saliva showed a radiation dose-dependent reduction at 3 days
and 3 and 9 months following 15 Gy of 93%, 82% and 73% (p<0.01), resp
ectively. Forty days after the 15 Gy irradiation the reduction was not
as severe (55%, NS). Three and 4.0 days post 15 Gy, amylase activity
demonstrated a similar pattern of reduction, 98% and 89% (p<0.01), res
pectively. In contrast to the P, no quantitative changes in the protei
n concentrations of the SM saliva were detected. As for the qualitativ
e profiles of separated proteins, no radiation-induced changes were fo
und for either P or SM at 3 and 40 days or 3 and 9 months, as compared
with controls. The electrolyte concentrations were found to be flow-r
ate dependent. The Na concentrations of P saliva at 3 and 40 days foll
owing 15 Gy were reduced by 65% and 83% (p<0.01), respectively. For SM
saliva, the Na concentrations were reduced at 40 days by 58% (p<0.05)
. The K concentration of P saliva increased at 40 days by 79% (P<0.05)
. The data suggest that the various observed sialochemical changes cou
ld result from a reduction in the salivary flow rate and/or the number
of surviving, normally functioning parenchymal cells. Thus, it is sug
gested that no salivary compositional alterations were directly induce
d by radiation but were secondary effects.