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To evaluate the therapeutic effect of heated (60 degrees C) lipiodol via hepatic artery administration in a rabbit model of VX2 liver cancer.Thirty male New Zealand white rabbits were randomly divided into three groups with 10 rabbits assigned to each group. VX2 carcinoma cells were surgically implanted into the left hepatic lobe. The tumors were allowed to grow for 2 weeks, and studies were performed until the diameter of the tumors detected by ultrasonograph reached 2-3cm. Under anesthesia, trans-catheter hepatic arterial embolization was performed and doxorubicin-lipiodol (37 degrees C) (1mL), lipiodol (60 degrees C) (1mL) or control (physiological saline (37 degrees C) (1mL)) solution was injected into the hepatic arteries of animals in the three groups. One week later, the volume of the tumor was measured by ultrasonograph again. The serum of all rabbits was collected before injection and at 4 and 7 days after injection, and the level of aspartate aminotransferase (AST) was checked. The survival period of the three groups of rabbits after treatment was also recorded. During the last course of their disease, the rabbits were given analgesics to relieve suffering.The tumor growth rate in the lipiodol (60 degrees C) group (0.92+/-0.21, tumor volume from 1811+/-435 to 1670+/-564mm(3)) was significantly lower than that in the control group (3.48+/-1.17, tumor volume from 1808+/-756 to 5747+/-1341mm(3)) (P0.05) and in the doxorubicin-lipiodol (37 degrees C) group (1.69+/-0.26, tumor volume from 1881+/-641 to 2428+/-752mm(3)) (P0.05). Consequently, the survival period of the animals in the lipiodol (60 degrees C) group (41.0+/-3.0 days) was significantly greater than that in the doxorubicin-lipiodol (37 degrees C) group (38.0+/-2.5 days) (P0.05). On the other hand, there was no statistically significant difference in serum AST levels between the lipiodol (60 degrees C) group (148.2+/-11.3UL(-1)) and the doxorubicin-lipiodol (37 degrees C) group (139.7+/-12.3UL(-1)) (P0.05). However, the serum AST level in the lipiodol (60 degrees C) group was significantly higher at 4 days after injection (P0.05) than in the control group (68.6+/-6.6UL(-1)).Treatment with lipiodol (60 degrees C) resulted in an effect on serum AST levels similar to that caused by treatment with doxorubicin-lipiodol (37 degrees C). Thus, lipiodol (60 degrees C) treatment could greatly prolong the survival period of rabbits with VX2 cancer by inhibiting tumor growth.

The present studies were undertaken to examine if the impaired vascular function observed in diabetes is attributed to the altered levels of G-protein. Diabetes was induced in Sprague Dawley rats by a single intraperitoneal injection of streptozotocin (STZ) (60 mg/kg body wt) and after a period of 5 days, the aorta were used for adenylyl cyclase activity determination and protein quantification. A temporal relationship between the expression of Gialpha proteins and development of diabetes was also examined on day 1, 2, 3, 4 and 5 of injection of STZ. Blood glucose levels were significantly increased from day 1 in STZ-rats as compared to their counterpart control rats and reached to about 20 mM on 3rd day and 30 mM on 5th day. The expression of Gialpha-2 and Gialpha-3 proteins as determined by immunoblotting techniques was decreased by about 70 and 50% respectively in aorta from STZ rats compared to the control rats after 5 days of treatment, whereas 40% decrease in Gialpha-2 and Gialpha-3 was observed after 3rd day of STZ injection. On the other hand, the expression of Gsalpha was unaltered in STZ rats. In addition, the stimulatory effect of cholera toxin (CT) on GTP-mediated stimulation of adenylyl cyclase was not different in STZ as compared to the control group. However, the stimulatory effects of isoproterenol, glucagon, NaF and FSK on adenylyl cyclase activity were significantly enhanced in STZ rats as compared to control rats, whereas basal adenylyl cyclase activity was significantly lower in STZ-rats as compared to control rats. In addition, GTPgammaS inhibited FSK-stimulated adenylyl cyclase activity in concentration-dependent manner (receptor-independent functions of Gialpha) in control rats which was completely attenuated in STZ-rats. In addition, receptor-mediated inhibitions of adenylyl cyclase by angiotensin II, oxotremorine, atrial natriuretic peptide (ANP99-126) and C-ANP4-23 were also attenuated (receptor-dependent functions of Gialpha) in STZ-rats. These results indicate that aorta from diabetic rats exhibit decreased levels of cAMP and decreased expression of Gialpha. The decreased expression of Gialpha may be responsible for the altered responsiveness of adenylyl cyclase to hormonal stimulation and inhibition in STZ-rats. It may thus be suggested that the impaired adenylyl cyclase-Gialpha protein signaling may be one of the possible mechanisms responsible for the impaired vascular functions in diabetes.

It was reported that heating can enhance sensitivity of rabbit VX2 cell to adriamycin and increase intracellular concentration of adriamycin. This study was designed to evaluate the anti-tumor effects of interventional hyperthermia and interventional chemotheramotherapy on VX2 carcinoma in rabbit liver.VX2 carcinoma cells were surgically implanted into the right liver lobe of 60 male New Zealand white rabbits, which were randomly divided into 4 groups(15 rabbits per group). To inject physiological saline(37 degrees C), adriamycin (37 degrees C), physiological saline(60 degrees C), and adriamycin (60 degrees C) in different groups via hepatic artery of the rabbits with liver cancer. One week later, to observe the volume of tumor, the serum level of aspartate transaminase(AST), and observe the survival period of VX2 rabbits.In group of ADM(60 degrees C), the tumor growth rate (0.53 +/- 0.21)% was significantly lower than group 2(1.09 +/- 0.26)%, group 3(3.32 +/- 1.28)%, and group 4(3.48 +/- 1.17)% (P0.05, P0.05, P0.01, respectively). The survival period of adriamycin (60 degrees C) group (50.0 +/- 2.0)d was significantly higher than the untreated control group (40.5 +/- 3.0)d, (P0.05). The serum level of AST of TNP-470 with lipiodol group was not higher than the other treated groups(P0.05), but being significantly higher than the untreated control group after treated(P0.05).Adriamycin (60 degrees C) greatly decreases the tumour growth rate, and prolongs the survival period.