Effects of thyroid hormone on myocardial T-type calcium channels at mRNA and protein levels in rats / 中国病理生理杂志

AIM:To observe the effect of thyroxine on the expression of T-type calcium channels Cav3. 1, Cav3. 2 and Cav3. 3 in rat myocardium, and to explore the possible biological mechanism between the changes of the ex-pression of T-type calcium channels and the arrhythmia in hyperthyroid heart disease. METHODS:Healthy SD rats (n=20) were randomly divided into normal control group (n=10) and hyperthyroid heart disease group (n=10). The animal model was established by intraperitoneal injection of levothyroxine for 35 d. The contents of T3 and T4 in serum, the heart-to-body weight ratio, the diameter of cardiac myocytes and electrocardiograph were measured to evaluate hyperthyroid heart disease. Moreover, the mRNA and protein expression levels of T-type calcium channels in the myocardium were measured by RT-PCR, immunohistochemistry and Western blot. RESULTS:After intraperitoneal injection of levothyroxine for 35 d, compared with the normal control group, the serum contents of T3 and T4, the heart-to-body weight ratio and the diameter of cardiac myocytes were significantly increased in hyperthyroid heart disease group (P<0.05), and arrhythmia occurred in hyperthyroid heart disease group. By immunohistochemistry and Western blot, the protein expression of Cav3. 1 in-creased significantly (P<0.05), while the protein expression of Cav3.2 decreased significantly (P<0.01). However, no change of the Cav3. 3 protein was observed. The results of RT-PCR were the same as immunohistochemistry and Western blot. CONCLUSION:Thyroxine promotes the expression of Cav3. 1 in the myocardium but inhibits the expression of Cav3. 2 at mRNA and protein levels, which might be involved in arrhythmia in hyperthyroid heart disease.

Diatoms Distribution in Ningbo Three-river Watershed during Summer / 法医学杂志

OBJECTIVES@#To explore the species, quantity and distribution of diatoms in Ningbo three-river watershed during summer and to provide scientific basis for forensic examination of drowning cases in the waters of Ningbo.@*METHODS@#Water samples were collected in July and August of 2015. Fourteen water sampling points were selected from the Yao River, the Fenghua River and the Yong River. The morphological features of diatom species and dominant diatoms were distinguished by microscope.@*RESULTS@#A total of 16 species of diatoms were detected in the Yao River, the Fenghua River and the Yong River. Melosira was the dominant species in the Yao River, and the quantity and richness were higher than in other rivers. The richness of Cyclotella in the Yong River was higher than in other rivers. The richness of Pinnularia and Licmophora were higher in the Fenghua River than in the Yao River and the Yong River.@*CONCLUSIONS@#The species and proportion of diatom is different in each river. Database of the species and relative composition for the diatoms in corresponding river is established, which may provide data support for forensic examination of drowning cases in Ningbo three-river watershed.

Effect of triptolide on iNOS and SP expressions in spinal dorsal horn and dorsal root ganglion of rats with adjuvant arthritis / 中国中药杂志

<p><b>OBJECTIVE</b>To observe the analgesic effect of triptolide (TP) of high, middle and low doses on rats with adjuvant arthritis (AA), and the expressions of inducible nitric oxide synthase (iNOS) and substance P (SP) in spinal dorsal horn and dorsal root ganglion (DRG) of corresponding sections, in order to discuss the possible mechanism for the analgesic effect of TP on rats with adjuvant arthritis.</p><p><b>METHOD</b>Fifty SD rats were selected and randomly divided into the normal group (group A), the model group (group B), and TP low (group C), middle (group D), high (group E) dose groups. Except for the group A, all of the remaining groups were injected with 0.1 mL of Freund's complete adjuvant through their right rear toes to establish the model. At 14 d after the model establishment, rats in C, D and E groups were intraperitoneally injected with different doses of TP (0.1 mg x kg(-1) for the group C, 0.2 mg x kg(-1) for the group D, 0.4 mg x kg(-1) for the group E) once a day for 9 days. Then the 50% mechanical withdraw threshold (MWT) was determined. And the expressions of iNOS and SP in lumbar5 (L5) spinal dorsal horn and DRG were detected with the immunohistochemical method.</p><p><b>RESULT</b>The 50% MWT of rats in the group B was significantly lower than that of the group A (P < 0.01). After being treated with TP, the Thermal withdrawal latencies of groups C, D and E were significantly higher than that of the group B (P < 0.01). TP could notably increase the MWT of AA rats, with a certain dose-effect relationship. The immunohistochemical results indicated that the iNOS and SP expressions significantly increased in the group B (P < 0.01), while the positive expression levels of iNOS and SP in groups C, D and E were significantly lower than that of the group B (P < 0.01), with a certain dose-effect relationship.</p><p><b>CONCLUSION</b>TP shows a good analgesic effect on AA, and could inhibit the iNOS and SP expressions in spinal dorsal horn and DRG in rats with adjuvant arthritis, which may be one of action mechanisms for the analgesic effect of TP.</p>

Influence of triptolide on neuronal apoptosis in rat with cerebral injury after focal ischemia reperfusion / 中国中药杂志

<p><b>OBJECTIVE</b>To study effect of triptolide (TL) on neuronal apoptosis in cerebral tissue of rat after ischemia-reperfusion.</p><p><b>METHOD</b>Triptolide at dose 0.2 or 0.4 mg x kg(-1) was intraperitoneally injected once a day for 4 d. The focal cerebral ischemia-reperfusion model was established with thread embolism in middle artery before triptolide injection on the fourth day. Neurological deficit score of rats was evaluated; and immunohistochemical techniques were used to count positive cells of express of MPO and TUNEL in cerebraltissue.</p><p><b>RESULT</b>Compared with the control group, the deficit of neural function was significantly improved, and the number of infiltrate of neutrophil and neuronal apoptosis in cerebral tissue was remarkably reduced in two TL-treated groups.</p><p><b>CONCLUSION</b>The results suggested that TL can inhibit infiltration of neutrophil and decrease the degree of neuronal apoptosis in cerebral tissue.</p>