Study Of Acetate Pb On The Developing Brain Damage Of Neonatal Rats And Its Protection

Objective To set up experimentally animal model of Pb-exposed neonatal rats, to examine the effect of Pb on the physical growth and developing brain damage bodily, cellularly and molecularly, and to appraise protective effect of JNYZ liquid. Method 5 brood of neonatal Wistar rats were used from the center of experimental animal of Suzhou University, and were randomly divided into the normal group, the low Pb and high Pb group. The animal model of Pb-exposed neonatal rats was set up with intraperitoneal injection of acetate Pb solution at birth and injection dose respectively use 0, 20, 60mg/kg. Neonatal rats were breastfeeding by their mother rats. The protective groups were intraperitoneally injected JNYZ liquid O.lml after injected Pb from birth to the end of experiment (17 days). Experimental examination index was that (1) effect of different dose Pb on physical growth and development of brain, such physical growth as bodyweight, brainweight, incisor eruption, eye opening, such early nerve reflex as cliff avoidance, surface righting, slope turning, such sense and motor development as auditory startle, visual placing, homing test, forward motion and swimming; (2) effect of different dose Pb on the biochemistry index of neonatal rats brain, such as the content of protein (Folin-phenol reagent Method), Spd, IAA and EAA (Thin Layer Chromatography), NO (Nitrate reductase Method) and SOD (Xanthosine oxidase Method); (3) The expression of Bax, Bcl-2 and NGFR in the nerve cell (Enzyme-immunohistochemistry); and (4) the protective effect of JNYZ liquid on developing brain damage of neonatal rats. Results (1) In the low Pb, high Pb group, Hb were respectively 86.9 + 3.9, 68.2 + 5.76, which were significantly lower than that in the normal group (t=3.76, 7.62; PO.01); moreover, between Hb and accumulativeabsorption of Pb, there was significantly negative correlation (r=-0.949; P<0.01); (2) In the low and high Pb groups, the bodyweight and brainweight were significantly decreased, compared with the normal group, and the appearance day of eye opening, cliff avoidance, surface righting, slope turning, auditory startle, forward motion and swimming were significantly retarded; (3) In the low and high Pb groups, the content of protein, Spd, IAA, SOD and NO of brain were significantly decreased than those in the normal group, however, EAA was significantly higher in the low Pb group, but was significantly lower in the high group than that in the normal group. Moreover, between accumulative absorption of Pb and the content of protein, Spd, IAA, SOD and NO of brain, there are significantly negative correlation (r=-0.724, -0.793, -0.824, -0.816, -0.67 respectively; PO.01); (4) In the low Pb group and high Pb group, the expression of Bcl-2 and NGFR in the nerve cell were significantly decreased, but the expression of Bax were significantly increased; (5) In protective groups with JNYZ liquid, compared with the damage groups respectively, not only the physical growth and development of brain as bodyweight, brainweight, eye opening, surface righting, swimming and so on were significantly improved, but also the content of protein, Spd, IAA, NO and SOD of brain were significantly higher, and the expression of Bcl-2, Bax and NGFR in the nerve cell were significantly different. Conclusion The animal damage model of developing brain of neonatal rats with Intraperitoneal injection of acetate Pb solution is of simple, convenient, reliable and controllable. The results indicated that Pb severely disturbs the growth of physique and developing brain. Application of JNYZ liquid plays an important role in protecting the developing brain damage induced by Pb exposure in the level of body, cell, molecular.