Thapsigargin-induced endothelium-dependent triphasic regulation of vascular tone in the porcine renal artery.

1. To elucidate the role of thapsigargin-induced Ca2+ entry in endothelial cells in the regulation of vascular tone, changes in Ca2+ and force of smooth muscle were simultaneously monitored in fura-2-loaded strips of porcine renal artery. 2. During phenylephrine-induced sustained contraction, thapsigargin caused an endothelium-dependent triphasic response; an initial relaxation, a subsequent transient contraction, and a sustained relaxation. The initial relaxation and the contraction were associated with a decrease and an increase in [Ca2+]i, respectively. There was no apparent [Ca2+]i decrease during the sustained relaxation. Thapsigargin-induced responses were observed at 10-8 M and higher concentrations, with the maximum response observed at 10-6 M. 3. The transient contraction was inhibited by a cyclo-oxygenase inhibitor (10-5 M indomethacin), a thromboxane A2 (TXA2)/prostaglandin H2 (PGH2) receptor antagonist (10-5 M ONO-3708), and a TXA2 synthase inhibitor (10-5 M OKY-046). 4. During the phenylephrine-induced contraction in the presence of indomethacin, thapsigargin caused an initial, but not a sustained relaxation, in the presence of Nomega-nitro-L-arginine methylester (L-NAME). During the contraction induced by phenylephrine plus 40 mM K+-depolarization in the presence of indomethacin, thapsigargin induced both a transient and a sustained relaxation. However, these relaxations were completely abolished in the presence of L-NAME. 5. Thapsigargin caused a large Ca2+ elevation in cultured endothelial cells of the renal artery. The concentration-response relation was thus similar to that for force development in the arterial strips. 6. In conclusion, thapsigargin-induced Ca2+ entry in endothelial cells led to triphasic changes in the tone of the porcine renal artery. The endothelium-dependent contraction was mediated mainly by TXA2. Nitric oxide and hyperpolarizing factor are both involved in the initial relaxation. However, a sustained relaxation was observed which mainly depended on nitric oxide.     

Purification and Partial Characterization of an Indomethacin Hydrolyzing Enzyme from Pig Liver

Purpose. Indomethacin is well known to be metabolized via O-demethylation and N-deacylation. In this paper we found an enzyme involved in the hydrolysis of amide-linkage of indomethacin and partially characterized it as well as its substrate specificity. Methods. An indomethacin hydrolyzing enzyme was purified to homogeneity from pig liver microsomes using columns of Q-Sepharose, Red-Sepharose and Blue-Sepharose. The enzyme activity was assayed by measuring of -chlorobenzoic acid liberated from indomethacin by HPLC. Results. The purified enzyme effectively hydrolyzed the amide linkage in indomethacin but not those in -naphthylacetate and -nitrophenylacetate, which are typical substrates for carboxylesterase. The subunit molecular mass of the enzyme was 65 kDa according SDS-polyacrylamide gel electrophoresis. The Michaelis constant (Km) and maximum velocity (Vmax) values for indomethacin were 67.8 µM and 9.02 nmol/min/mg protein, respectively. The amino acid sequence analysis of the enzyme after cyanogen bromide cleavage showed high homology with a mouse carboxylesterase isozyme designated as ES-male. The activity of indomethacin hydrolysis was relatively high in the pig, rabbit and human liver homogenate, but not in those from rat and mouse. On the other hand, purified human liver carboxylesterases pl 5.3 and 4.5, and pig liver carboxylesterases have no catalytic activity for indomethacin. Conclusions. These results indicate that the hydrolysis of amide-linkage of indomethacin in humans would be associated with an enzyme similar to the indomethacin hydrolyzing enzyme from pig liver microsomes described here.     

Effects of pirarubicin,an antitumor antibiotic,on the cardiovascular system

Summary In the present study we examined the effects of pirarubicin [(2R)-4-0-tetrahydropyranyladriamycin, THP] on a cardiovascular system. An injection of THP (0.39–3.13 mg/kg, i. v.) reduced the mean blood pressure and caused an increase in the respiratory air rate in anesthetized rats. At 1.5×10^–6–1.5×10^–5 m, THP markedly relaxed a contraction induced by 10^–7 m norepinephrine in rat aorta with endothelium but not in that without endothelium. At a dose of 0.02–0.5 mg, THP produced an increase in the contractile force and the perfusion flow of isolated perfused guinea pig hearts. At a higher concentration (4.5×10^–5–1.5×10^–4 m), it produced a slight increase in the contractile force of the left atria in guinea pigs. This positive inotropic action of THP was inhibited by diphenhydramine (10^–6–5×10^–5 m), chlorpheniramine (3×10^–7–3×10^–5 m), and tripelennamine (3×10^–7–3×10^–5 m) but not by propranolol (10^–6 m), cimetidine (10^–5 m), diltiazem (10^–6 m), or ryanodine (10^–8 m). THP given i. v. at 2.5 mg/kg elevated the plasma histamine level in anesthetized dogs. From these data, we conclude that THP mainly relaxed the rat aorta in the presence of endothelium and that at higher concentrations, it increased the contractile force in the cardiac muscle, probably mediated through the release of histamine.     

Long-term survival after radical resection of advanced pancreatic cancer

A 65-yr-old man who underwent pancreaticoduodenectomy with portal vein resection for pancreatic cancer is alive 8 yr after surgery. Originally, computed tomography (CT) revealed an 8-cm tumor in the pancreatic head. The tumor had infiltrated the portal vein, but grew expansively, so there was neither biliary obstruction nor jaundice. Pancreaticoduodenectomy with resection of the portal vein was performed for pancreatic cancer. Many tumor-infiltrating lymphocytes were seen within cancer cell nests on routine histopathology. We performed immunostaining for CD8, and found that a large number of the lymphocytes were CD8⁺ T cells. The patient’s prognosis was considered poor because the tumor was large and had infiltrated the portal vein. We suspect that long-term survival may be related to the response of CD8⁺ T cells to the cancer.     

抗体夹心酶联免疫吸附法测定重组E.coli L-门冬酰胺酶研究

用重组E.coliL-门冬酰胺酶免疫家兔，DEAE-纤维素柱层析纯化IgG，采用二步戊二醛交联法将辣根过氧化物酶标记抗体，建立抗体夹心酶联免疫吸附法，测定大鼠血浆中重组E.coliL-门冬酰胺酶浓度。本测定方法的线性范围为1～64U/L，灵敏度为0.4U/L。建立的抗体夹心酶联免疫吸附法测定大鼠血浆中重组E.coliL-门冬酰胺酶具有良好的精密度、回收率、灵敏度和特异性。     

Penile metastasis from renal cell carcinoma: a case report

Penile metastasis is rare. It occurs in the advanced stage of genitourinary cancer, with many other metastases in various organs. All 7 patients with penile metastasis of renal cell cancer, reported in the Japanese literature, died within a year. Our case was not the exception. A 69-year-old male presented with right flank pain and penile induration. Right renal cancer with liver invasion and multiple pulmonary metastases were found. Microscopic examination revealed a sarcomatous pattern. He died 4 months later.     

Typus melancholicus and the Temperament and Character Inventory personality dimensions in patients with major depression

Although many clinical studies have been conducted to determine the etiological role and clinical implications of typus melancholicus for unipolar depression, maladaptive personality features in depressive patients have not been well described. This study explores typus melancholicus, as measured by the rigidity subscale of the Munich Personality Test, and maladaptive personality features, as measured by the Temperament and Character Inventory (TCI), in 131 remitted patients with DSM-IV major depression and 154 normal controls. The patients reported significantly higher scores on rigidity and harm avoidance and significantly lower scores on self-directedness and cooperativeness. Only 23.6% of the variance of the rigidity scale was explained by the variance of the seven TCI scales, in which only persistence was significantly correlated positively to rigidity. Cluster analysis identified four subgroups, two of which were characterized by a high rigidity score. One of these two subgroups showed no maladaptive personality features, as measured by the TCI, while the other showed high harm avoidance and low self-directedness. These results indicate that the personality of depressive patients is characterized not only by typus melancholicus but also by maladaptive personality features, that typus melancholicus is not well represented by any TCI scale, and that typus melancholicus and maladaptive personality features can coexist in some depressive patients.