ABSTRACT
Objective To observe the impairment of different doses of cyclosporine A (CsA) to the rat myocardial tissue to offer scientific evidence for the long-term safe application of CsA in heart transplantation. Methods Eighty-four female Wistar rats, each weighing of (200 ± 25)g, were randomly divided into 12 groups. On days 7,14,21 after a constant peritoneal injection of CsA(0,5,10,15 mg/kg) and 1 ml physiological saline in control group, the rats were put to death, the rat myocardial tissue taken, to observe the pathologic and structural changes of the tissue cells under light microscope and electron microscope. The contents of rat myocardium tissue malondialdehyde(MDA) and superoxide dismutase(SOD) were measured;cardiomyocyte apoptosis was detected and accounted, apoptosis index(AI) was measured with the method of TUNEL. Results Small dose of CsA(5 mg/kg)had no obvious effects on cardiac tissue, in CsA groups of 10 mg/kg and 15 mg/kg, under the light microscope, there appeared edema, degeneration and necrosis of myocardium, part of cardiac myocyte had different level cavity;under the electron microscope, there appeared mitochondria damage, nucleus shrinkage and chromatic margination, part of cardiac myocyte had focus cavity. There was dilated endoplasic reticulum in the sarcoplasm. The effects of different time and dose on MDA content of rat myocardium tissue had statistical significance (F = 6.37,10.15, both P < 0.05). Interaction between time and dose existed statistical significance (F=7.14, P< 0.05). The MDA contents of CsA group of 10 mg/kg and 15 mg/kg were [(2.29 ± 0.18), (3.10 ± 0.45), (2.57± 0.37)nmol/L] and [(3.09±0.63), (3.32 ±0.52), (3.34 ± 0.29)nmol/L] on days 7,14,21 after a constant peritoneal injection of CsA, which were obviously higher than the control group [(1.98 ± 0.20), (2.04 ± 0.52), (1.99 ± 0.26) nmol/L, all P < 0.05], respectively. The effects of different time and dose on SOD activity of rat myocardium tissue had statistical significance(F = 8.43,11.69, both P < 0.05). Interaction between time and dose existed statistical significance(F = 9.86, P < 0.05). The SOD activity of CsA groups of 10 mg/kg and 15 mg/kg were (15.95 ± 1.00), (12.74 ± 1.31), (14.01 ± 0.81)nmol/L and (13.04 ± 1.01), (14.68 ± 0.81), (14.01 ± 0.63)nmol/L on days 7,14,21 after a constant peritoneal injection of CsA, which were obviously higher than the control group [(10.38 ± 0.80), (9.73 ± 0.58), (10.20 ± 0.26)nmol/L, all P < 0.05], respectively. Apoptosis nucleus appeared huffy or brown under the light microscope. The effects of different time and dose on AI of rat myocardium tissue had statistical significance (F = 10.02,20.46, both P < 0.05). Interaction between time and dose existed statistical significance (F = 15.73,P < 0.05). The AI of CsA groups of 10 mg/kg and 15 mg/kg were (6.91 ± 0.70)%, (11.10 ± 2.05)%,(19.81 ± 5.00)% and (11.02 ±2.02)%,(15.51 ± 1.31)%,(33.40±6.60)% on days 7,14,21 after a constant peritoneal injection of CsA, which were obviously higher than the control group [(4.40 ± 0.13)%, (4.60± 1.20)%, (5.20 ± 1.10), all P < 0.05] and CsA group of 5 mg/kg [(4.60 ± 0.10)%, (5.00±2.11)%, (5.43± 1.11)%, all P < 0.05], respectively. Conclusion Small dose of CsA has no obvious effects on cardiac tissue, but large dosage can induce myocyte apoptosis and damage by causing oxidative stress;after implantation, attention should be paid to cardiac impairment due to constant large dosage of CsA.
ABSTRACT
<p><b>OBJECTIVE</b>To study the geographical variation of morphologic and germination characteristic of different Glycyrrhiza uralensis provenance seeds, approach the geographical variation mode and ecology mechanism, and laid theoretical foundation for districting and allocating of G. uralensis seeds.</p><p><b>METHOD</b>Field investigation and laboratory analysis were applied. Seed shape and kilosseed weight were sampled randomly, germination rate germination force by general methods.</p><p><b>RESULT</b>The morphologic characteristic of G. uralensis seeds showed roughly longitude variation tendency that the seeds increased gradually from west to east. While the germination characteristic showed roughly altitude variation tendency that the seeds germination rate and germination force increased with the increase of the altitude, and the average germination rate was the same with the seeds morphologic characteristic. The results of analysis correlated with the climatic factors show that the morphologic characteristic of G. uralensis was positive correlated with annual rain-fall of the habitat, and the germination rate was quickened by drought, high temperature and strong sunshine.</p><p><b>CONCLUSION</b>The morphologic and germination characteristic and of G. uralensis seeds present distinguished geographical variation, and the formation of the variation was related to the ecological environment in which the seed provenance adapted.</p>