Changes in Tissue Metals After Cadmium Intoxication and Intervention With Chlorpromazine in Male Rats

Cadmium (Cd), one of the most dangerous heavy metals, has a very similar ionic radius to calcium (Ca). The interference of cadmium in calcium homeostasis may play an important role in cadmium toxicity. Recent reports indicate that calmodulin (CaM) inhibitors such as trifluoperazine and chlorpromazine (CPZ) could protect rodents against cadmium toxicity. It was also reported that pretreatment of mice with zinc (Zn) could reduce the adverse effects induced by cadmium. The aim of this study is to determine whether Cd changes the balance of other essential metals such as Zn and copper (Cu) in rat tissues, and whether CPZ can reverse these changes which are induced by cadmium intoxication. Adult male Sprague Dawley (SD) rats were injected intraperitoneally (ip) with cadmium chloride (CdCl 2) (0.2, 0.4, 0.8 mg Cd/kg body weight) alone and 0.4mg Cd/kg in association with CPZ (5 mg/kg) daily for a week. The control animals were injected with normal saline only. The results showed that the cadmium content in the liver, kidney and testis increased significantly with a dose response relationship. Cadmium treatment markedly increased the Zn and Ca content in some of the tissues. Hepatic and renal metallothionein (MT) increased significantly after cadmium intoxication. CPZ treatment, however, reduced cadmium content in liver, but not blood and kidney. CPZ seemed to decrease the content of MT in liver and significantly increase the amounts of MT in kidney. These data suggest that the intervention of cadmium with tissue essential metals may play a role in cadmium toxicity in rats, and calmodulin inhibitors to some extent can reduce the adverse effect of cadmium by decreasing the cadmium load in tissues and reversing the unbalance of essential metals.

The Tissue Reactions and Changes of a Surface of Various Metal Implants after Their Introduction in a Bone Tissue in Experiment

Screw metal implants (3S, Israel) with rough or smooth polished surface were introduced in a tibial proximal condyle of not purebred rabbits. The condition of surrounding tissues in 2 and 6 months after implantation was compared by light microscopy and X-ray methods. Within 6 months after operation the considerable distinctions of radiological and morphological data were revealed not. 2 months later after introduction of implants with a rough surface the effort enclosed for its twisting is, much more, than for removal of the polished product. However, stability of fixing of implants was practically made even at 6 months. On remote rough implants there is a set of tissue scraps whereas on products with a smooth surface the tissue remains were much less. Surrounding tissues strongly join a rough surface, grow into cavities, and during removal of such products there is a considerable trauma of tissues round an implantation place. Smooth implants have the smaller area of contact with organism tissues, they are fixed due to bicortical implantation, during removal easily get out and don’t break off surrounding tissues. The signs of inflammation and formation of merged multinuclear macrophages were not found at all cases, which give evidence to the inertness of material of the mentioned articles for living organism. In some observations however and by implantation of the rough article and by introduction of polished implants, metal particles were found, but after use of the foreign body with grit-blasted treatment of surface metal was found more frequently, and its fragments had larger volume.

Effect of Astragalus complanatus flavonoid on anti-liver fibrosis in rats

AIM： To observe the anti-liver fibrosis effect of Astragalus complanatus fiavonoids （ACF） in rats. METHODS： The liver fibrosis model in rats was established by injecting interperitoneally 0.2 mL/100 g 0.5% dimethylnitrosamine, thrice a week. Meanwhile, the rats were administered ACF （30, 60, 120 mg/kg） or colchicine （0.1 mg/kg） once a day for 1 mo. Serum N-propeptide of type Ⅰ procollagen （PINP） and type Ⅲ procollagen （PⅢNP） was measured using ELISA. Malondialdehyde （MDA） and superoxide dismutase （SOD） in hepatic tissue were evaluated. Matrix metal protease-1 （MMP-1） mRNA expression was assayed by RT-PCR and the protein expression of tissue inhibitor of metal protease-1 （TIMP-1） was analyzed by immunohistochemistry. RESULTS： In the ACF groups, SOD activity increased and MDA content decreased in comparison to the liver fibrosis model group. The serum PINP and PⅢNP contents in ACF-2 and -3 group decreased compared to those in model group. In ACF-2 and -3 group, the expression of MMP-1 mRNA increased significantly and the protein expression of TIMP-1 decreased compared to that in model group. CONCLUSION： The antifibrotic mechanisms of ACF are associated with its influence on lipid peroxidation and collagen synthesis and degradation.