Age-related alteration of alpha(1)-adrenoceptor mechanisms and Ca2+ inhibitory effects of isradipine

The effects of age on alpha1-adrenoceptor and Ca2+ channel-mediated contractile mechanisms in the thoracic aorta, isolated from rats of 3, 6, 10, 18 and 40 weeks old, were studied. The potency (pD(2) value) of norepinephrine increased with age from 3 to 10 weeks, but decreased thereafter from 10 to 40 weeks. The change in pD(2) value of norepinephrine was proportional to the logarithm of the maximum number of binding sites (B(max)), obtained in the [(3)H]prazosin binding study. The inhibitory effect of a potent Ca(2)+ channel blocker, israpidine, on the norepinephrine-induced contraction decreased with age from 3 to 10 weeks, but increased in rats aged 10 to 40 weeks. An inverse relationship between the change in isradipine inhibition, the maximum reduction of isradipine on norepinephrine-induced contraction and the logarithm of B(max) was found. The inhibitory effect of a nonselective Ca2+ channel blocker, SKF96365, on the norepinephrine-induced contraction did not change with age. The amplitude of the Ca2+-induced sustained contraction, after pretreatment with isradipine (10(-7) M) in the presence of norepinephrine (10(-6) M), increased with age from 3 to 10 weeks, but decreased thereafter in rats aged 10 to 40 weeks. There was no significant difference in the slope of the regression lines between the cytosolic Ca(2)+ level ([Ca2+]i) and the tension in the presence of norepinephrine at different ages. These results suggest that the changes in alpha(1)-adrenoceptor mechanisms and the reduction by isradipine with age are due to changes in the alpha1-adrenoceptor density and the population of Ca2+ channels, but not to changes in the affinity of drugs to the alpha1-adrenoceptor or Ca2+ sensitivity of contractile elements of aortic smooth muscles.

Gene expressions of cholecystokinin (CCK) and CCK receptors, and its satiety effect in young and old male rats

Cholecystokinin (CCK), one of the first discovered gastrointestinal hormones, which stimulates pancreatic enzyme secretion and induces gallbladder contraction, is one of the most abundant neurotransmitter peptides in the brain and is implicated in satiety via CCK-A receptors. We compared the suppressive effect of central administration of CCK on food intake in young and old rats. The suppressive effect on food intake was enhanced in old rats. To examine the mechanism of this enhanced suppression, we measured the mRNA levels of CCK, CCK-A and CCK-B receptors in the cerebral cortex and the hypothalamus of young and old male rats. The mRNA level of CCK-A receptors in the hypothalamus decreased with age, whereas the mRNA levels of CCK-B receptors in the hypothalamus and cerebral cortex did not. The mRNA level of CCK in the cerebral cortex decreased significantly in old rats, although the decrease in the hypothalamus was not significant. Therefore, the enhanced sensitivity to CCK of old rats could not be explained by changes in gene expressions of CCK and CCK receptors. Moreover, the effects of aging on the gene expressions of CCK-A and CCK-B receptors were different.

Partial sequence of ribulose-1,5-bisphosphate carboxylase/oxygenase and the phylogeny of Prochloron and Prochlorococcus (Prochlorales)

The prochlorophytes, oxygenic photosynthetic prokaryotes having no phycobiliprotein but possessing chlorophylls a and b, have been proposed to have a common ancestry with green chloroplasts, yet this is still controversal. We report here that partial sequence comparisons of the large subunit of ribulose-1,5'-bisphosphate carboxylase/oxygenase, including sequence data from two prochlorophytes, Prochlorococcus and Prochloron, indicate that Prochlorococcus is more closely related to a photosynthetic bacterium, Chromatium vinosum (gamma-purple bacteria), than to cyanobacteria, while Prochloron is closely related to the prochlorophyte Prochlorothrix and to cyanobacteria. The molecular phylogenetic tree indicates that a common ancestor of Prochlorococcus and gamma-purple bacteria branched off from the land plant lineage earlier than Prochloron, Prochlorothrix, and cyanobacteria.

Biochemical characterization of a Ca(2+)-dependent lectin from the hemolymph of a photosymbiotic marine bivalve, Tridacna derasa (Röding)

A Ca(2+)-dependent lectin was purified from the hemolymph of a photosymbiotic bivalve, Tridacna derasa. An electrophoretically homogeneous form was obtained by using affinity chromatography with Sepharose 4B. More than 80% of the hemolymph protein was accounted for by this lectin. The apparent molecular mass of the lectin, in its native form exhibiting hemagglutinating activity, was estimated by gel filtration analysis to be approximately 480 kDa. On sodium dodecyl sulfate-polyacrylamide gel electrophoresis, in the absence of reductants, it migrated as a single band corresponding to a very large size, while in the presence of 2-mercaptoethanol, it migrated as two distinct bands of 23 and 46 kDa. These results indicate that the subunits were linked by disulfide bridges to form the native protein. After reducing pyridylethylation, each of the 23- and 46-kDa polypeptides was isolated by gel filtration in a mobile phase containing guanidine-HCl. The two polypeptides had the same amino-terminal sequence and a similar amino-acid composition, and in the presence of 2-mercaptoethanol gave a single band on isoelectric focusing at a pH of 6.0. The results suggested that the 46-kDa peptide is a homodimer of 23-kDa subunits held together by a covalent bond other than a disulfide linkage. This lectin required calcium ions for its activity. By ultraviolet spectrophotometry the association constant for the calcium ion was determined to be 0.88 mM. The hemagglutinating activity decreased dramatically below pH 6.5, but re-increased to the original level when the solution was neutralized. Such a pH-dependent alteration of the ligand-binding activity was similar to that found in vertebrate asialoglycoprotein receptors.(ABSTRACT TRUNCATED AT 250 WORDS)

Decline in glucose metabolism in the brain in neuronal ceroid lipofuscinosis (NCL) in English setter--evidence by positron emission tomography (PET)

Positron emission tomography scans were performed on brains of homozygous and heterozygous English setters with neuronal ceroid-lipofuscinosis (NCL) from 13 months of age to 24-25 months of age for homozygous dogs and to 38 months for heterozygous dogs, respectively. After iv injection of 18F-fluorodeoxyglucose (FDG), 7 coronal brain scans as well as sequential arterial blood samplings were performed for 45 min under pentobarbital anesthesia. From these data, three different functional images (DAR (standardized uptake value), FDG uptake (fractional uptake) and glucose uptake) were reconstructed and quantitatively analysed. In the age range from 13 to 15 months, glucose images were comparable for both homozygous and heterozygous dogs, so that no differentiation was possible between healthy and diseased dogs on the basis of PET findings. Between 18 and 24 months of age, a drastic decline in glucose metabolism was observed in homozygous dogs, while the decline in glucose utilization was very mild in this period for heterozygous dogs. Furthermore, in PET scans, cerebral atrophy and ventricular enlargement were clearly shown in homozygous dogs. Consequently at the age from 20 to 24 months, a clear differential diagnosis between healthy (heterozygous) and diseased (homozygous) dogs became possible even if the clinical symptoms were still not clear in the latter. We conclude that the biochemical alterations in the brain in canine NCL occurs and progresses very rapidly in the last quarter of their lives.

Lack of satiety effect of cholecystokinin (CCK) in a new rat model not expressing the CCK-A receptor gene

This work expands recent observations that Otsuka Long-Evans Tokushima Fatty (OLETF) rats show little or no pancreatic expression of the cholecystokinin (CCK)-A receptor gene. We examined whether the CCK-A and -B receptor genes were expressed in the brain (hypothalamus) of OLETF rats in comparison with control (Long-Evans Tokushima Otsuka = LETO) rats. CCK-A receptor mRNA was detected in the hypothalamus of LETO rats but not OLETF rats. The CCK-B receptor gene was expressed in the hypothalamus in both strains. Cerebroventricular administration of CCK-8 sulfate inhibited daily food intake in LETO rats, but not in OLETF rats. These results show that in OLETF rats the absence of CCK-A receptor gene expression in the hypothalamus results in hyperphagia because of lack of satiety.

(-)Deprenyl increases the life span as well as activities of superoxide dismutase and catalase but not of glutathione peroxidase in selective brain regions in Fischer rats

(-)Deprenyl, a MAO-B inhibitor that is also known to be effective for symptoms of Parkinson's disease, when injected subcutaneously (sc) in male Fischer-344 rats at a dose of 0.5 mg/kg per day (3 times a week) from 18 months of age, significantly increased the remaining life expectancy. The average life span after 24 months was 34% greater in treated rats than in saline-treated control animals. Furthermore, a short-term (3 wk) continuous sc infusion of deprenyl significantly increased activities of superoxide dismutase and catalase but not of glutathione peroxidase in selective brain regions such as s. nigra, striatum, and cerebral cortex, but not in hippocampus or cerebellum, or the liver. The optimal dose for increasing these activities, however, differed greatly depending on the sex and age of animals, with a 10-fold lower value for young female than male rats. Interestingly, aging caused an increase and a decrease in the optimal dose in female and male rats, respectively. In addition, treatment for a longer term tended to reduce the optimal dosage in the same animal group. The results clearly demonstrate that deprenyl increases antioxidant enzyme activities in selective brain regions. If this effect of deprenyl is causally related to its life-prolonging effect, the dosage to be used for any life span study would be a critical factor, with the dosage differing widely depending on sex, age of animal, and mode and duration of drug administration.

The effect of a long term (6 months) treatment with (-)deprenyl on antioxidant enzyme activities in selective brain regions in old female Fischer 344 rats

The effect of long term treatment with (-)deprenyl (s.c. injection three times a week for 6 months) on superoxide dismutase (SOD) and catalase (CAT) in selective brain regions was examined in old (22 months) female Fischer 344 rats. The three doses of deprenyl used (0.1, 0.25 and 0.5 mg/kg/day) increased the activities of both enzymes in substantia nigra, striatum and cerebral cortices essentially in a dose dependent manner. However, for CAT activities in cerebral cortices, the smallest dose of 0.1 mg/kg/day was most effective, while the highest dose (0.5 mg/kg/day) had no effect. In contrast to these brain regions, there were no significant differences in enzyme activities between control and deprenyl-treated groups in the hippocampus and cerebellum. If the effect of deprenyl on the life span of female F-344 rats is causally related to its effect on antioxidant enzyme activities in selective brain regions as shown in this study, then a dose of 0.25 or 0.5 mg/kg/day appears to be most appropriate. Since this dose is much lower than the dose suggested by our previous short term (3 week) experiments, an even longer term experiment is necessary to determine the optimal dose of deprenyl to increase free radical scavenging and thus possibly extend lifespan.

Tauro alpha-muricholate is as effective as tauro beta-muricholate and tauroursodeoxycholate in preventing taurochenodeoxycholate-induced liver damage in the rat

Male Wistar rats were infused intravenously with taurochenodeoxycholate (0.4 mumol/min/100 gm) alone (group A) or with one of the three bile salts (tauroursodeoxycholate [group B], tauro beta-muricholate [group C] or tauro alpha-muricholate [group D]) at a rate of 0.2 mumol/min/100/gm for 1 hr. One-hour bile flow and bile salt excretion rates were significantly lower in group A than in the other three coinfused (B, C, D) groups. Biliary 1-hr outputs of lactate dehydrogenase and albumin in the bile, on the other hand, were significantly higher in group A than in the other groups. Plasma concentrations of lactate dehydrogenase at the time of killing (1 hr) were two to three times higher in group A than in the other groups. Although tauro alpha-muricholate does not possess a 7 beta-hydroxy group, the 6 beta-hydroxy group that tauro alpha-muricholate possesses thus appears to be as effective as a 7 beta-hydroxy group in reducing the liver damage caused by toxic bile salts such as taurochenodeoxycholate. The so-called hepatoprotective effects of tauroursodeoxycholate and tauro beta-muricholate found in previous studies may require explanation(s) other than the presence of a 7 beta-hydroxy group in their molecular structures.

Ursodeoxycholic acid reduces the systemic toxicity of 1,2-dichloro,4-nitrobenzene by stimulating hepatic glutathione S-transferase in mice

Male C57BL/6 mice were fed with normal diet (ND) or diets containing 0.3 or 0.5% ursodeoxycholic acid (UDCA) for 3 weeks. Glutathione S-transferase (GST) activities in the liver cytosolic fraction of these animals toward 1,2-dichloro,4-nitrobenzene (DCNB) as well as to 1-chloro,2,4-dinitrobenzene (CDNB) were significantly increased in a dose dependent manner in UDCA-treated groups compared with the control (ND-fed) animal group (one-way ANOVA). Reduced glutathione (GSH) levels tended to slightly decrease with UDCA diets but the difference did not attain a statistical significance (P > 0.05, one-way ANOVA). Twenty four hr survival rates after an oral challenge of 3.5 mg/kg of DCNB were significantly higher (P < 0.05, Chi-square test) in the two UDCA fed groups (10/10 for 0.5% group, 8/11 for 0.3% group) compared with the control group (3/11). Thus, UDCA appears to reduce the systemic toxicity of DCNB which is detoxified by the hepatic GST system. Although UDCA has been shown to exert hepatoprotective effects in experimental animals and humans in the past, to the best of our knowledge, the present study is the first report that UDCA reduces the systemic toxicity of a toxicant which is detoxified by the hepatic GST system. Although a direct proof is not available, it is most likely that the reduction of the systemic toxicity of DCNB was achieved by the increase in GST activity caused by UDCA feeding. This finding may open a new research field with regard to the unique biological properties of this bile salt in modulating hepatic detoxifying enzymes.

(-)deprenyl increases activities of superoxide dismutase and catalase in certain brain regions in old male mice

A subcutaneous continuous infusion of (-)deprenyl for 3 weeks in old C57BL male mice increased superoxide dismutase (SOD) and catalase (CAT) activities in s. nigra, striatum and cerebral cortex but not in hippocampus, cerebellum or liver. The doses of 0.5 and 1.0 mg/kg/day were most effective, while with a higher dose (2.0 mg/kg/day), deprenyl tended to lose its effect slightly and with a lower dose (0.25 mg/kg/day) deprenyl was clearly less effective. The results suggest that deprenyl can increase antioxidant enzyme activities in certain brain regions in mice as was previously demonstrated in rats of both sexes and different ages; this raises the possibility that deprenyl has this particular effect in animal species other than rats.

Tauro alpha-muricholate has a biliary transport maximum (Tm) value equivalent to that for tauroursodeoxycholate and tauro beta-muricholate in the rat

Our previous studies have shown that Tm values for tauroursodeoxycholate (TUDC) and tauro beta-muricholate (T beta-MC) are more than two-fold higher than that for taurocholate (TC) in the rat. The present study attempted to clarify whether tauro alpha-muricholate (T alpha-MC) also has such an unusually large Tm value in the rat. Under nembutal anesthesia, male Wistar derived rats (body weight 280-300 g, 13 wks in age) were continuously infused with T alpha-MC solution. The infusion rate was raised stepwise every 20 min, until the bile flow began to decline. Bile was collected every 10 min and bile salt excretion rate was determined. The average of the highest three excretion values was assumed to be the Tm in each animal. The Tm value of T alpha-MC was found to be 2.86 +/- 0.36 mumol/min/100 g (mean +/- SD, n = 4), which was even greater than Tm values for TUDC (2.59 +/- 0.39 mumol/min/100 g, n = 4) and T beta-MC (1.93 +/- 0.31 mumol/min/100 g, n = 4) as we reported previously. The relationship between the bile flow rate (microliter/min/100 g, Y axis) and bile salt excretion rate (mumol/min/100 g, X axis) was highly linear [Y = (6.00 +/- 0.29) x +(6.60 +/- 1.88), P < 0.001, r = 0.95, n = 54]. The slope value for T alpha-MC (6.00 +/- 0.29 microliters/mumol) was significantly higher than that for TUDC (4.76 +/- 0.71 microliters/mumol) and was comparable to that for T beta-MC as we previously found for these bile salts in this rat strain. The results suggest that T alpha-MC has a very efficient transport system in this species as was observed for the other two bile salts that have a 7 beta-hydroxy group (TUDC and T beta-MC). This efficient transport system thus appears to be shared not only by bile salts specifically having a 7 beta-hydroxy group, but also by other bile salts such as T alpha-MC that have a 6 beta-hydroxy group but not a 7 beta-hydroxy group.

[Antibiotic prophylaxis for transurethral resection of the prostate--comparison of oral administration therapy with intravenous administration therapy]

To compare the prophylactic effect of oral and intravenous antibiotics against postoperative fever and urinary tract infection (UTI) after transurethral resection of the prostate (TUR-P), we conducted a multi-center prospective randomized study. The incidence of pyrexia over 38 degrees C was defined as the primary endpoint. One hundred and fifty patients with sterile urine before TUR-P were entered into this study. The patients were allocated randomly into the two arms; arm A cefotiam 4 g a day for 7 days, arm B tosufloxacin 300 mg a day for 7 days, based on the stratification into the 4 groups determined with/without preoperative indwelling catheters and with/without the history of preoperative UTI. Of these patients, 143 were eligible. We divided 124 patients without preoperative UTI and without indwelling catheters as the "low risk group", and the other 19 patients with preoperative UTI and/or with indwelling catheters as the "high risk group". In the low risk group, 9 patients out of 63 (14.3%) in arm A and 6 out of 61 (9.8%) in arm B had pyrexia during 7 postoperative days. The incidence of fever in arm B was 4.4% less than that in arm A and the 95% confidence limit was from -7% to 16%. In the high risk group, 4 out of 11 (36.4%) patients in arm A and none of 8 in arm B had fever but the difference was not significant. The incidence of post operative UTI in the low risk group on the 4 to 5, 9 to 12, 23 to 26 and 37 to 40 postoperative days was 8.3, 16.4, 25.0 and 23.9% in arm A and 6.7, 16.7, 29.6 and 36.7% in arm B, respectively. The prophylactic effect of oral administration of tosufloxacin is equivalent to that of the intravenous administration of cefotiam. The use of oral antibiotics is beneficial to reducing the cost of medication.

Taurine conjugate of ursodeoxycholate plays a major role in the hepatoprotective effect against cholestasis induced by taurochenodeoxycholate in rats

Rats which were taurine-deprived through beta-alanine administration and untreated rats were used to elucidate the mechanism of hepatoprotective effects of ursodeoxycholate (UDC). Animals were infused with taurochenodeoxycholate (TCDC, 0.4 mumol.min-1.100 g-1) alone or in combination with tauroursodeoxycholate (TUDC), or with UDC (both 0.6 mumol.min-1.100 g-1) for 2 h. Ursodeoxycholate as well as TUDC prevented severe cholestasis and liver damage induced by TCDC infusion in both untreated and taurine-deprived rat groups. In untreated rats, however, UDC was less effective in hepatoprotection than TUDC as indicated by sequential changes in biliary LDH output during the period of 30 to 120 min (P < 0.05). In rats receiving UDC and TCDC, total biliary output of LDH for 2 h was significantly higher in taurine-deprived rats than that in the control (73.40 +/- 10.10 vs 41.14 +/- 12.56: P < 0.05), suggesting that the difference became greater upon taurine deprivation. In contrast, in rats receiving TUDC and TCDC, the protective effect was comparable for the taurine-deprived and untreated rats. When the animals were infused with UDC and TCDC, taurine-deprived rats exhibited a biliary excretion rate for TUDC half that of control rats (P < 0.05). Furthermore, a highly significant correlation was observed between the biliary excretion rate of TUDC and biliary output of LDH (r = -0.886, P < 0.0001). These results suggest that UDC conjugates, especially TUDC, and not UDC may play a major role in the prevention of cholestasis and liver cell damage caused by TCDC infusion.

[A case of bilateral synchronous renal cell carcinoma treated with partial nephrectomy with temporary occlusion of the segmental renal artery (segmental nephrectomy)]

We present a case of bilateral synchronous renal cell carcinoma. A 57-year-old man visited our hospital with a complaint of fever up. On ultrasonography and computerized tomography scan, a round tumor about 2.5 cm in diameter in the posterior portion of the right kidney and another tumor about 7 cm in diameter arising from the upper pole of the left kidney. Selective renal arteriogram showed that the inferior branch of the posterior segmental artery supplied blood to the right renal tumor. Left partial nephrectomy with temporary occlusion of the main renal artery and posterior segmental nephrectomy of the right kidney were performed at the same time. In patients with cancer confined to the posterior segment of the kidney, segmental nephrectomy can be performed while allowing unimpaired perfusion to the remainder of the kidney from the main renal artery.

Nucleotide sequence of the Mn-stabilizing protein gene of the thermophilic cyanobacterium Synechococcus elongatus

The nucleotide sequence of the psbO gene encoding the extrinsic 33 kDa protein (the Mn-stabilizing protein) from the thermophilic cyanobacterium Synechococcus elongatus was determined. The deduced amino acid sequence consisted of 272 residues; 26 for the signal peptide and 246 for the mature protein. The amino acid sequences of nine proteolytic peptides from the isolated protein completely agreed with the deduced amino acid sequence. Several unique variations of amino acids were found in the primary structure, of which some may be related to the high thermostability of the protein.

Chronic treatment of (-)deprenyl prolongs the life span of male Fischer 344 rats. Further evidence

Seventy male Fischer 344 (F-344) rats were treated with s.c. injection of (-)deprenyl (0.5 mg/kg, n = 35) or physiological saline (n = 35) 3 times a week from the age of 18 months until the time of their natural death. The fifty percent survival time was 28 months in control animals and 30 months in the deprenyl treated group. The mean survival time after the start of treatment (18 months) and after 24 months were 378.3 +/- 97.4 days (mean +/- SD) and 196.3 +/- 97.4 days, respectively, in deprenyl treated rats and 328.7 +/- 108.8 days and 146.7 +/- 108.7 days in control rats. The increases in average life expectancies caused by deprenyl treatment (15% from 18 months and 34% from 24 months) were both statistically significant (P < 0.05, two-tailed t-test). The average body weights were comparable for both groups but the variation of body weight was greater in control groups, thus excluding the possibility that the life prolonging effect of deprenyl results from reduced dietary intake. The results confirm those of two previous studies (1,2) which reported a significant life prolonging effect of deprenyl in aged rats and lend added support to the results of a study on male F-344 rats where the effect was only marginally significant (16% increase after 24 months, P = 0.048 by one-tailed t test) (2).

The optimal dosage of (-)deprenyl for increasing superoxide dismutase activities in several brain regions decreases with age in male Fischer 344 rats

We previously reported that the optimal dosage of (-)deprenyl to increase superoxide dismutase (SOD) activities in striatum in rats differs 10 fold between young male and female rats (1). Furthermore, in female rats the optimal dosage increased with age (1). In the present study in order to clarify how the optimal dosage of this effect changes with age in male rats, we examined the effects of four different dosages of deprenyl on SOD enzyme activities in striatum and several other tissues in old (28-29-month-old) male Fischer 344 (F-344) rats. Continuous s.c. infusion of deprenyl for 3 wks increased activities of SOD and catalase (CAT) in striatum, substantia nigra and cortical regions but not in hippocampus, cerebellum or the liver. The dose of 0.5 mg/kg/day was found to be most effective, while higher (1.0, 2.0 mg/kg/day) or lower (0.1 mg/kg/day) dosages were less effective. This value of 0.5 mg/kg/day was 4 fold lower than the dosage of 2.0 mg/kg/day which was most effective in increasing SOD and CAT activities in young (5-7 month old) male rats of the same strain (1,2). The decline of the optimal dosage with age found in male rats is best explained by a possible decline with age in the hepatic microsomal monooxygenase enzyme activities that are involved with the metabolism of deprenyl. In view of the large differences in the optimal dosages shown among different sexes and ages of rats, future studies regarding the unique effect of this drug in prolonging the life span of rats must be carefully investigated with the caution in mind that the optimal dosage for the life prolonging effect may well differ depending on sex, age and possibly strain and species of animal model used.

Sequential changes in activities of superoxide dismutase and catalase in brain regions and liver during (-)deprenyl infusion in male rats

A continuous s.c. infusion of (-)deprenyl in young male rats at a dose of 2.0 mg/kg/day for 1 week significantly increased total superoxide dismutase (SOD) activities due to increases in both Cu Zn-SOD and Mn-SOD activities in certain brain regions such as the substantia nitra and striatum, but not in the hippocampus or cerebellum, or in the liver. With continuing infusion, enzyme activities of SOD were further increased in the following weeks, reaching a plateau at 3 weeks. In some cerebral cortices the increase became significant at 3 weeks. In contrast to SOD activities, an increase in catalase (CAT) activity became significant only after 2 weeks of infusion, and only in the brain regions where SOD activities were increased earlier. The delay in the increase in CAT activity following deprenyl infusion suggests that this increased CAT activity is an adaptive response to the earlier increase in deprenyl-induced SOD activities rather than a direct effect of deprenyl on CAT activity, although the latter possibility cannot be excluded.

[A case of CA19-9 producing transitional cell carcinoma of the ureter effectively responsive to combination chemotherapy]

We report a case of CA19-9 producing transitional cell carcinoma of the right ureter effectively responsive to combination chemotherapy (methotrexate, vinblastine, doxorubicin and cisplatin (M-VAC) regimen) in a 53-year-old woman. The maximum level of serum CA19-9 showed 3,000 U/ml and clinical staging of the tumor was T4 N3 M0. Marked regression of the tumor was identified by computed tomographic scan and the level of serum CA19-9 returned to the normal range after 3 courses of M-VAC therapy. Right total nephro-ureterectomy and partial cystectomy was done and the surgical specimen revealed no viable tumors. She is alive without evidence of local recurrence or metastasis at 6 months after resection. The serum CA19-9 level was useful for monitoring the clinical course.

Difference in response of hepatic glutathione S-transferase activities to protein-free diet between young and old C57/BL male mice

Responses of hepatic glutathione S-transferase (GST) activities to protein-free diet (PFD) and normal diet (ND) refeeding were compared for young (6-month-old) and old (22-month-old) C57/BL male mice. Enzyme activities toward 1-chloro-2,4-dinitrobenzene (CDNB) were not significantly different between young and old rat livers in the basal condition without diet manipulation. When animals were fed PFD for 1 week, GST activities toward CDNB significantly declined in both age groups in comparison to respective basal values, but there was no significant difference in activities between the two age groups after a 7-day PFD. When they were refed with ND for 2 days (on day 2 of ND), the activities in young mice rose to a level significantly higher than the corresponding basal value. In contrast, in old animal livers, the activity slightly but further tended to decline on day 2 of ND. Activities in old rat livers returned to the basal level on day 5 of ND, while activities in young animal livers that increased to levels higher than basal levels due to the overshoot returned to the basal level on day 7 of ND. Enzyme activities toward 1,2-dichloro-4-nitrobenzene (DCNB) were significantly higher in young rat livers than in old ones at the basal period. However, enzyme activities also overshot the basal level on day 2 of ND after 7-day PFD in young mouse livers, while in old mouse livers the activities were lowest on this day. Activities returned to the basal level on day 7 of ND in both age groups. Thus, the greatest difference in enzyme activities between young and old mouse livers for both substrates was observed on day 2 of ND after 7-day PFD, rather than at either the basal period or immediately after 7-day PFD. The results essentially agree with our previous findings on female C57/BL mice as well as female Fischer-344 rats, suggesting that the age-induced changes in the GST system become clearly manifest after diet manipulation of PFD followed by ND refeeding, rather than in values during a basal period without diet manipulation, regardless of sex or species of animal.

Age-related changes in antioxidant enzyme activities are region and organ, as well as sex, selective in the rat

Enzyme activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px) were determined in the liver as well as several specific brain regions of young and old Fischer-344 rats of both sexes. In the liver of male rats, activities of CAT as well as Mn-SOD were lower, while activities of Cu Zn-SOD were higher in old (30-month-old) rats than in young (7-month-old) ones. Activities of total SOD as well as GSH Px were comparable for young and old male rat livers. In contrast to male rats, in female rat livers, activities of CAT were significantly higher in old (28-months-old) rats, while activities of Mn-SOD were slightly (but significantly) higher in old rat livers. In old male rats, activities of Mn-SOD were significantly higher than in young males in several specific regions of the brain (the substantia nigra (s. nigra), striatum, hippocampus) but lower in the cerebellum. In particular, SOD activities in s. nigra, striatum and hippocampus in old male rats were several fold higher than corresponding values in young male rats. Activities of Cu Zn-SOD were generally unchanged with age. Activities of CAT as well as GSH-Px (both Se-dependent and non-Se-dependent forms) were also relatively unaffected by age. In female rat brains, activities of Mn-SOD as well as those of others all remained mostly unaffected by aging, although there was a general tendency of slightly higher activities in most cerebral regions for Mn-SOD in old female rats. Thus, age-related changes of these antioxidant enzymes in the liver and brain are markedly sex dependent and some enzyme activities (such as CAT in the liver) change in an opposite direction with age. Changes of Mn-SOD in the brain were markedly region-specific in male rats. Results suggest that the significance of the changes of these antioxidant enzyme activities during aging needs to be carefully interpreted, taking into consideration the fact that changes are markedly variable depending on sex as well as the organs and brain regions examined.

[A case of renal cell carcinoma in a horseshoe kidney]

We report a 68-year-old man with renal cell carcinoma in a horseshoe kidney. Abdominal computed tomography revealed a left renal tumor in a horseshoe kidney, and we carried out left radical nephrectomy. Histopathological diagnosis was renal cell carcinoma. Only 19 cases of renal cell carcinoma in a horseshoe kidney have been reported in Japan, and our case was the 20th.