Morris K J, Launder K A, Morgan A, Hornby S B, Collier C G
Biomedical Research, AEA Technology, Harwell, Didcot, Oxon, U.K.
Exp Toxicol Pathol. 1995 May;47(2-3):179-82. doi: 10.1016/S0940-2993(11)80311-8.
The durability of three experimental glass fibres (X7753, X7484, and X7779) was investigated in vivo. These fibres had in vitro dissolution rates of 600, 150, and 2 ng cm-2 hour-1, respectively. Three groups of female Fischer-344 rats were intratracheally instilled with a 1.2 mg suspension of one of each of the fibre types. All fibres had previously been neutron activated, to produce radioactive 24Na within the glass, which served as a radiotracer. At 2 days post instillation (PI) about 1 x 10(6) glass fibres were within the pulmonary region of the lung. Animals were killed at various time points from 2 to 360 days PI. Fibres were recovered from the animal lungs by hypochlorite digestion. The retention and morphometry of these fibres was investigated, and preliminary results are presented. After 360 days in the lung, the number of X7753 and X7484 fibres fell respectively to 10% and 50% of those present at 2 days PI. There was no detectable reduction in the number of X7779 fibres in the lung over this period. Morphometric analyses demonstrated a 53% and 22% reduction in the mean length of the X7753 and X7484 fibres, after 360 days in the lung. Reduction in diameter was apparent after only 28 days for the these fibre types. No change in the mean size of the X7779 fibres was observed during the study. The fibre morphometry data suggested that short fibres dissolved at a slower rate than long fibres. In general the in vivo fibre retention and morphometry data reflected the measured in vitro dissolution rate.
对三种实验性玻璃纤维（X7753、X7484和X7779）的体内耐久性进行了研究。这些纤维的体外溶解速率分别为600、150和2 ng cm-2 小时-1。将三组雌性Fischer-344大鼠经气管内分别注入1.2 mg每种纤维类型的悬浮液。所有纤维此前均已通过中子活化，以便在玻璃内部产生放射性24Na，其作为放射性示踪剂。在滴注后2天（PI），肺部区域内约有1×10(6)根玻璃纤维。在滴注后2至360天的不同时间点处死动物。通过次氯酸盐消化从动物肺部回收纤维。对这些纤维的留存情况和形态测量进行了研究，并给出了初步结果。在肺部放置360天后，X7753和X7484纤维的数量分别降至滴注后2天时的10%和50%。在此期间，肺部X7779纤维的数量未检测到减少。形态测量分析表明，在肺部放置360天后，X7753和X7484纤维的平均长度分别减少了53%和22%。对于这些纤维类型，仅在28天后直径就明显减小。在研究期间未观察到X7779纤维平均尺寸的变化。纤维形态测量数据表明，短纤维的溶解速度比长纤维慢。总体而言，体内纤维留存和形态测量数据反映了体外测量的溶解速率。
