Objective To establish a rat model of radiation-induced optic neuropathy ( RION) by delivering a single radiation dose to the optic chiasm. The aim of our study was to analysis the feasibility and effectiveness of manganese-enhanced magnetic resonance imaging ( MEMRI) in RION. Methods 34 Wistar rats were randomized to the control group(4 rats), the 2-month group(5 rats),the 4-month group(4 rats) and the 6-month group(11 rats) according to the different feeding period after irradiation. MEMRI scan were performed when the respective feeding periods of all groups expired. The rats were then killed for histological studies with hematoxylin and eosin stain, Luxol Fast Blue stain, and electron microscopy analysis. Results The ratio of RION in the four groups were 0/3, 1/5, 2/4 and 11/11, respectively (χ2 =15?443, P<0?05). There was an inverse correlation between the relative optical density value in the LFB stain and the interval between irradiation and pathological examination(R= -0?643,P<0?05). The number of glial cells in the HE stain in the four groups were 194 ± 65, 234 ± 19, 124 ± 11 and 345 ± 98, respectively(R=0?590,P<0?05). When compared MEMRI scan with the corresponding histological examination, we found that there was loss of signals of optic nerve on MEMRI imaging in one of 5 rats in the 2-month group, while no significant histological difference was found between this rat and the others. Conclusions RION can be non-invasively detected and semi-quantitative analysed by MEMRI scan. Moreover, RION can be early diagnosed by MEMRI scan which is capable to show physiological change in advance of pathological change.

OBJECTIVETo evaluate the effect of additives on absorption of Coptis chinensis total alkaloid and their pharmacokinetics in mice.

METHODThe mice were fed with the mixture of C. chinensis total alkaloids and additives (1:1). And then the feces and orbital blood were taken to detect the content of total alkaloids by HPLC and their pharmacokinetics.

RESULTGlutin could make the absorption of jatrorrhizine, coptisine, berberine and total alkaloids increased by 30%. Tween 80 and arabic gum did not affect the absorption of berberine, but inhibit that of other alkaloids. There had no influence of lecithin on the absorption of alkaloids. The peak time of total alkaloids in blood were 2 h (Cmax 1=5.9 mg x L(-1)) and 5.0 h (Cmax 2=3.4 mg x L(-1)), respectively, AUC was 17.6 mg x h x L(-1), the elimination of Half-life t1/2 was 5.2 h. After addition of glutin, the peak time of total alkaloids in blood were 1.5 h (Cmax 1=7.6 mg x L(-1)) and 4.8 h (Cmax 2=8.5 mg x L(-1)), AUC was up to 31.1 mg x h(-1) x L(-1), the elimination of Half-life t1/2 was 6.2 h.

CONCLUSIONGlutin could accelerate the mice on the absorption of C. chinensis total alkaloids, to extend the elimination half-life, increase the blood concentration and bioavailability.

Absorption ; drug effects ; physiology ; Alkaloids ; blood ; pharmacokinetics ; Animals ; Berberine ; analogs & derivatives ; blood ; Chromatography, High Pressure Liquid ; Coptis ; chemistry ; Diterpenes ; pharmacology ; Drug Interactions ; Female ; Food Additives ; pharmacology ; Half-Life ; Male ; Mice