ABSTRACT
Objective To explore the susceptibility differences of ventricular arrhythmia (VA ) in SHR rats with/without left ventricular hypertrophy(LVH) and the significance .Methods The experiments were performed on isolated hearts of 8‐week(the non‐LVH control group ,n=12) ,16 week‐old SHR(the LVH group ,n=12) and age‐matched Wistar Kyoto rats(Wistar ,the blank control group ,n=12) ,which were perfused in Langendorff mode with oxygenated Krebs‐Henseleit solution followed by a K+‐defi‐cient solution .The epicardial electrocardiogram was continuously monitored during all experiments .HE staining and collagen vol‐ume fraction(CVF)was used to evaluate the condition of LVH .Results Compared with the non‐LVH control group and the blank control group ,the low K+ induced ventricular arrhythmia occurred earlier with increased incidences and duration in the hearts of the LVH Group ,the incidences of ventricular tachycardia(VT) ,transient ventricular fibrillation(TVF) ,sustained ventricular fibrillation (SVF) and CVF were higher in the hearts of the LVH Group(P<0 .05) ,myocardial cell hypertrophy and myocardial cells intersti‐tial increased .Conclusion The ventricular arrhythmia occurred earlier with increased incidences and duration in the LVH tissue of SHR rats ,which implies that LVH is associated with VA .
ABSTRACT
<p><b>OBJECTIVE</b>The purpose of the present study was to investigate the relation between the dose of tumor cell inoculation (especially the doses less than minimum required to evoke tumor growth) and the anti-tumor immune system, particularly lymphoblast formation and cytotoxic activity of lymphcytes.</p><p><b>METHOD</b>We inoculated rats with various doses of SST-2 tumor cells and examined natural killer (NK) cell activity and lymphoblast formationin vitro.</p><p><b>RESULT</b>The results showed that the cytotoxicities against SST-2 cells and lymphoblast formation of lymphocytes were enhanced by small dose inoculation of tumor cells that could not induce tumor growth.</p><p><b>CONCLUSION</b>It was suggested that was lymphocutes play an important role as an anti-tumor immune system at small doses of tumor inoculation, which appears to reflect an early stage of tumor growthin vivo. It was also suggested that SST-2 tumor inoculation might be a useful model for studying the anti-tumor immune response in SHR rats.</p>
ABSTRACT
Objective: The purpose of the present study was to investigate the relation between the dose of tumor cell inoculation (especially the doses less than minimum required to evoke tumor growth) and the anti-tumor immune system, particularly lymphoblast formation and cytotoxic activity of lymphcytes. Method: We inoculated rats with various doses of SST-2 tumor cells and examined natural killer (NK) cell activity and lymphoblast formation in vitro. Result: The results showed that the cytotoxicities against SST-2 cells and lymphoblast formation of lymphocytes were enhanced by small dose inoculation of tumor cells that could not induce tumor growth. Conclusion: It was suggested that was lymphocutes play an important role as an anti-tumor immune system at small doses of tumor inoculation, which appears to reflect an early stage of tumor growth in vivo. It was also suggested that SST-2 tumor inoculation might be a useful model for studying the anti-tumor immune response in SHR rats.