Bopindolol is a slowly dissociating beta 1-adrenoceptor antagonist when compared to other beta-blockers

This study used radioligand binding assay methods and pharmacological experiments to examine whether bopindolol, possessing a long-lasting action in addition to potent beta-adrenoceptor antagonistic effects, is a slowly dissociating antagonist. In addition, the slow dissociation of two of its metabolites, 18-502 (4-(3-tert-butylamino-2-hydroxypropoxy)-2-methyl indole) and 20-785 (4-(3-tert-butylaminopropoxy)-2-carboxyl indole), which have potent beta-blocking activities, was also assessed. The blockade of 3H-CGP12177 binding sites in rat heart and brain induced by pindolol was readily reversed by washing, whereas this inhibition by bopindolol and 18-502 was not easily reversed by washing. In addition, specific bindings of the hearts of the treatment animals with 20-785, atenolol, (+/-)propranolol, nadolol and celiprolol and of washout were 86.7, 78.8, 77.5, 82.3 and 79.9% of the control, respectively. These blockades by the treatment of each drug and washout in the brain were, however, lower than those in the hearts. On the other hand, when the left and right atria were pretreated with propranolol, bopindolol and 18-502, the inotropic and chronotropic actions of isoprenaline were inhibited by these drugs even though they were not present in the extracellular medium. Pretreatment with 20-785, atenolol and nadolol was readily reversed for both inotropic action and chronotropic rate, and inhibition by celiprolol and pindolol remained at 25% of the control at 240 min after treatment with these drugs. A good correlation between inhibitory binding percentage in the hearts and inhibitory inotropic or chronotropic actions were observed, although it was not observed in the brain.(ABSTRACT TRUNCATED AT 250 WORDS)

Residual inhibition in density of [3H]isradipine binding sites in rat brain membrane pretreated with amlodipine

AIM

To test changes in the density of [3H] isradipine binding sites in rat brain membrane pretreated with amlodipine and to compare with those of nifedipine and (+) SM-6586 (methyl 1, 4-dihydro-2, 6-dimethyl-3-(3-(N-benzyl-N-methylaminomethyl)-1,2,4- oxadiazolyl-5-yl)-4-(3-nitrophenyl) pyridine-5-carboxylate).

METHODS

The membrane-enriched fractions were prepared from rat brain. The brain membranes were preincubated with nifedipine (10 nmol L-1), amlodipine (1 mumol L-1) and SM-6586 (1 nmol L-1) or with no antagonists added for 45 min, and washing and centrifugation were performed 3 times. They were assayed with [3H]isradipine in incubation media. The Kd and Bmax values of the membrane fractions pretreated with the drugs were determined by Scatchard analysis.

RESULTS

The blockage of the [3H]isradipine binding sites induced by nifedipine was reversed by washing, enabling the low values of the specific binding sites to be observed. The blockages by amlodipine and SM-6586, on the other hand, were not readily reversed. No significant difference was found, however, between in the Kd walues of these drugs.

CONCLUSION

Amlodipine and SM-6586 are Ca2+ antagonists which dissociate slowly from the Ca2+ channel in membranes.

[Early changes at anastomotic sites of saphenous vein grafts after coronary artery bypass grafting]

Saphenous vein grafts are known to develop intimal fibrocellular proliferation, however, there is little information regarding early changes of intimal fibrocellular proliferation after coronary artery bypass grafting (CABG). This study is based on 6 distal anastomotic sites obtained at autopsy from 3 patients who died within 9 days after CABG. The anastomotic sites were sectioned serially and studied with conventional and immunocytochemical techniques. Endothelial cells at all anastomotic sites showed desquamations. In two cases at 2 and 3 days after CABG, the luminal surfaces of anastomotic sites were covered by fibrin-platelet thrombus with infiltration of T-lymphocytes and macrophages. At these sites, moreover, some spindle-shaped cells were also present. Immunocytochemically, these spindle-shaped cells, which were stained with vimentin but negative with both anti-actin markers HHF35 and CGA7, were considered to be de-differentiated smooth muscle cells. In the case at 9 days after CABG, cellular reactions were mainly composed of macrophages and de-differentiated smooth muscle cells. In conclusion, these observations in human saphenous vein grafts at an early stage suggest that 1) endothelial denudation leads to adhesion of fibrin-platelet thrombus and subsequent cellular response. 2) T-lymphocytes and macrophages may play an important role in an early stage of intimal fibrocellular proliferation.

[A case of massive air embolism during cardiopulmonary bypass]

Massive air embolism during cardiopulmonary bypass is one of the most serious complications in open heart surgery. We report such an accident, which was managed by temporary retrograde perfusion through the superior vena cava. A 59-year-old woman with severe mitral stenosis underwent mitral valve replacement. Soon after the start of the bypass, a massive air embolism occurred, probably because a bend in the tubing caused the blood level in the oxygenator to fall. The pump was stopped immediately and the patient was placed in the deep Trendelenburg position. The pump circuit was primed rapidly with fluid and retrograde perfusion through the superior vena cava was done at a flow rate of 1.5 L/min for 5 min. After air return from the aortotomy was confirmed, the standard bypass procedure was resumed with hypothermia. When the accident was discovered, and until the end of the operation, deep anesthesia was induced with pentobarbital for protection of the brain. Mitral valve replacement and tricuspid annuoplasty were done in the usual way thereafter. Postoperatively, the patient had no neurologic sequelae except for transient generalized convulsions, and has returned to normal daily activities.

Comparison of dopamine contents in lung vasculature of several species

Catecholamine contents of human, rabbit and rat pulmonary vasculature were surveyed. Human pulmonary vasculature was obtained from lobectomized specimens of lung tumors. Catecholamines were measured by high performance liquid chromatography after aluminum extraction. High dopamine (DA) content (1.4 nmol/g wet weight) and high DA/noradrenaline (NA) ratio (17.9%) were observed in rabbit pulmonary arterial trunks. In rabbit pulmonary arterial branches, DA content was 0.26 nmol/g wet weight and DA/NA ratio was 4.2%. In rat, NA contents were less in intra- and extra-pulmonary arteries (1.5 and 4.0 nmol/g wet weight, respectively) compared with pulmonary vasculature of rabbit or with the other vasculatures of the same animals. DA contents were 1.9 and 1.8 nmol/g wet weight in intra- and extra-pulmonary arteries, respectively, and DA/NA ratios were markedly high (218 and 48%, respectively). On the other hand, DA/NA ratios were around 1% in human intrapulmonary arteries and that for large-sized (more than 2 mm in diameter) intrapulmonary vein was 8.5%. Species difference and regional difference among pulmonary vascular beds are evident and at least in human pulmonary artery, DA/NA ratio is not as high as rabbit and rat pulmonary arteries.

Hemolytic anemia following high-dose intravenous immunoglobulin administration

We describe two cases of hemolytic anemia following high-dose intravenous human immunoglobulin administration in young females with idiopathic thrombocytopenic purpura. Inducement of hemolytic anemia by anti-A and anti-B antibodies in these cases necessitates the performance of a minor crossmatching procedure prior to immunoglobulin use to prevent the occurrence of this adverse reaction.

Localisation of dopamine D1-like and D2-like receptors in the pulmonary vasculature

The pharmacological profile and the anatomical localisation of dopamine receptor subtypes were investigated in the rabbit pulmonary vascular bed using combined radioligand binding and light microscope autoradiography techniques. Dopamine D1-like receptor sites, which probably belong to the dopamine D1 receptor subtype, were characterized in sections of lung using [3H]-SCH 23390 as a ligand. These sites were located within the tunica intima and the tunica media of large sized intrapulmonary artery branches and in the tunica media of medium sized intrapulmonary artery branches. Dopamine D2-like receptor sites, which probably belong to the dopamine D2 receptor subtype, were characterized using [3H]-spiroperidol as a ligand. These sites were located within the tunica adventitia of both extra- and intrapulmonary artery branches. Dopamine D2-like receptor sites were also found in the tunica adventitia of the human pulmonary artery, but not of the rat pulmonary artery. The different anatomical localization of dopamine D1 and D2 receptor subtypes in the pulmonary vasculature suggests that these sites are involved in the modulation of pulmonary vascular tone by interacting with different receptors unevenly distributed throughout the pulmonary vascular bed.

Cervical flexion myelopathy associated with cervical spina bifida occulta--case report

A 16-year-old boy presented with segmental muscular atrophy of the bilateral distal upper extremities. Cervical spine x-ray films showed occult spina bifida from C-1 to T-1 associated with an abnormal long club-like bone located parallel to the epidural space between C-5 and C-7. In neck flexion, the cervical spinal cord was stretched and compressed to the posterior aspect of the vertebral body. Moreover, the dorsally placed abnormal bone migrated ventrally, indenting the dorsal portion of the spinal cord. This is quite an unusual case of so-called "flexion myelopathy," aggravated by the abnormal bone located dorsally.

[Case of pseudocoarctation associated with aneurysm of the descending aorta]

A 55-year-old man was hospitalized for examination of a descending aortic aneurysm found on chest X-ray film. Aortogram and magnetic resonance imaging showed elongation and kinking of the arch and proximal descending aorta, which is associated with a descending aneurysm. A slit-like area of stenosis was found at the beginning of the aneurysm, but there was no pressure gradient across the stenotic lesion. The diagnosis of pseudocoarctation with aneurysm was done, and an operation was undertaken. The aneurysm and the kinking distal to the left subclavian artery were resected, and an artificial graft was inserted using partial cardiopulmonary bypass. This case is the tenth of pseudocoarctation associated with aneurysm reported in Japan.

Localization of dopamine receptors in the rabbit lung vasculature

The localization of dopamine receptor subtypes in the rabbit pulmonary circulation was investigated by using combined radioligand binding and light microscope autoradiography techniques. Dopamine D1-like receptors, probably belonging to the dopamine D1 receptor subtype, were demonstrated in sections of rabbit lung using [3H]-SCH 23390 as a ligand. This site is located within the tunica intima and the tunica media of large intrapulmonary artery branches (diameter > 300 microns) as well as within the tunica media of medium-sized pulmonary artery branches (diameter between 100 and 300 microns). No [3H]-SCH 23390 binding sites were found in small-sized pulmonary artery branches (diameter < 100 microns) or in pulmonary veins. Dopamine D2-like receptors, probably belonging to the dopamine D2 receptor subtype, were demonstrated with radioligand binding techniques in sections of extrapulmonary arteries but not of lung using [3H]-spiroperidol as a ligand. Light microscope autoradiography revealed the localization of this site within the tunica adventitia of extrapulmonary arteries as well as of large- and medium-sized intrapulmonary artery branches. The different anatomical localization of dopamine D1- and D2-like receptors in the rabbit pulmonary vasculature suggests that these sites are involved in the modulation of pulmonary vascular tone by interacting with different receptors having endothelial, muscular and probably prejunctional localization. The functional significance of the uneven distribution of dopamine receptor subtypes throughout the pulmonary vascular bed should be clarified in future studies.

Participation of endogenous noradrenaline in the release of ATP by high potassium in the rat caudal artery

Potassium (40 mM) evoked the release of adenine nucleotides and adenosine in rat isolated caudal arteries. This release was abolished by bunazosin. Endogenous noradrenaline was also released. Furthermore, the high potassium-induced purine release was abolished by rubbing the lumen of the vessel. These findings suggest that the high potassium releases endogenous noradrenaline, which subsequently elicits the release of ATP and related purines by acting on alpha 1-adrenoceptors on the endothelial cell.

[MRI of traumatic anosmia]

On MRI, the authors were able to demonstrate the contused lesions of bilateral rectal gyri near the crista galli in all of five cases of traumatic anosmia. Thin slice coronal and sagittal images of MRI were very useful for detecting the lesions. Conventional CT scans failed to demonstrate the lesions in 3 out of the 5 cases, but, even in these cases, MRI was able to clearly depict the contused lesions of bilateral rectal gyri. Therefore, the depicted lesions of bilateral rectal gyri on MRI can be evidence of traumatic anosmia and this may be very significant in medico-legal cases.

Differences in purinoceptor modulation of norepinephrine release between caudal arteries of normotensive and hypertensive rats

The effects of 2-chloroadenosine, a purinoceptor agonist, on the overflow of endogenous norepinephrine (NE) was examined in the electrically field-stimulated (EFS) caudal artery obtained from Wistar-Kyoto (WKY) rats and age-matched spontaneously hypertensive rats (SHRs). 2-Chloroadenosine at 10(-6) and 10(-5) M reduced the EFS-evoked release of NE from arteries of WKY rats but was without effect on the release of NE from arteries of SHRs. Methoxamine (10(-5) M), an alpha adrenoceptor agonist, caused the release of ATP, ADP, AMP and adenosine from caudal arteries of Wistar rats, WKY rats and SHRs, and decreased the release of EFS-evoked release of endogenous NE in arteries from normotensive rats, but not from arteries of SHRs. Thus, both exogenously applied and endogenously released purines are ineffective in reducing the evoked release of NE in this model of hypertension. The enhanced release of NE from sympathetic nerves of SHRs may be due in part to the loss of prejunctional modulation by purines.

Proliferating cell nuclear antigen cyclin in human transitional cell carcinoma

OBJECTIVES

To confirm the value of the proliferating cell nuclear antigen (PCNA) labelling index in relation to histological grade, stage and prognosis.

MATERIALS AND METHODS

Tissue specimens from 56 patients (49 men, 7 women; mean age 65 years [range 34-86]) with newly diagnosed transitional cell carcinoma of the urinary bladder were stained by an avidin-biotin peroxidase method using an anti-PCNA monoclonal antibody. Immunohistochemical analysis was performed on ethanol-fixed, paraffin-embedded tissue sections obtained by endoscopic biopsy or transurethral resection (TUR). The PCNA labelling index was determined by counting the number of PCNA-labelled cells in the tissue sections.

RESULTS

Grade 1 tumours averaged 5.1 +/- 3.0% labelling versus 10.9 +/- 5.2% in grade 2 tumours, and grade 3 tumours had a PCNA labelling index of 21.8 +/- 10.4%. The average labelling indices for superficial tumour (37 patients) and invasive tumour (19 patients) were 7.5 +/- 5.3% and 20.8 +/- 10.0%, respectively. A distant metastatic bladder tumour showed an average labelling index of 42.3%. To analyse survival, tumours with PCNA indices above and below the median level (12%) were compared. Those patients with an index of < 12% (the mean of all of the PCNA values) had a worse prognosis than those with an index of > 12%. The mean PCNA labelling indices in recurrent and non-recurrent tumours were 6.4 +/- 0.7% and 8.2 +/- 1.7%, respectively, statistically not significant.

CONCLUSION

The higher PCNA labelling index may indicate biological malignancy. These results suggest that measurement of the PCNA labelling index in bladder cancer may prove to be an objective and quantitative assay of biological aggressiveness and provide significant prognostic information, though it does not help to select patients at high risk of recurrence in superficial tumours.

Bispecific antibody-mediated cytotoxicity by CD4+ and CD8(+)-activated T cells generated from leukemia patients after allogeneic bone marrow transplantation

The F(ab')2 bispecific antibody (BSAb) was prepared from anti-CD3 moAb and anti-CD10 moAb. The BSAb could react with both CD3+ T cells and CD10+ leukemia cells and triggered T cell-mediated cytotoxicity. To apply the BSAb to prevention of leukemic relapse after BMT, we investigated the generation of both CD4+ and CD8+ anti-tumor effector T cells from patient's PBMC 14 days after BMT. Neither CD4+ T cells nor CD8+ T cells, which were activated with immobilized anti-CD3 moAb plus IL-2, could lyse CD10+ leukemia cells by themselves, but they showed augmented cytotoxicity against CD10+ leukemia cells by targeting with anti-CD3 x anti-CD10 BSAb. Moreover, the activated CD4+ T cells were demonstrated to produce IL-2 and IFN-gamma when they were cultured with CD10+ leukemia cells in the presence of the BSAb. The BSAb-mediated cytotoxicity of activated T cells was demonstrated not only against the recipient leukemia cells but also against third party leukemia cells. These results suggested that anti-CD3 x anti-CD10 BSAb might be a good tool to prevent relapse after BMT in combination with activated CD4+ T cells and CD8+ T cells.

[The squash technique for silver staining of argyrophilic nucleolar organizer regions on bladder tumors: comparison with paraffin embedded sections]

We examined nucleolar organizer region (NOR) indices on 13 bladder tumors on both squash-prepared specimens and paraffin embedded specimens stained by silver-colloid method. It was noted that; 1. The nuclear size was enlarged by squashing, 2. Aggregated NOR dots were dispersed, 3. Uniformity of microscopic phase of the dots was obtained, 4. Squash specimens had more precise countabilities than the paraffin embedded sections for avoidance of nuclear resection. NOR indices (mean +/- S.D.) of those bladder tumors on squash-preparation and paraffin section were 8.64 +/- 4.32 and 6.13 +/- 1.58, respectively, and the former showed good correlation with the tumor stage. When we prepare the squashed specimen from the surgically resected bladder tumor tissue, embedding and sectioning processes which are inevitable for preparation of paraffin embedded section, could be eliminated. Thus, squash-smear technique was considered to be better than the method using paraffin embedded section on the point of shorter duration of examination and accurate countability of the NOR dots.

The importance of dose intensity in chemotherapy of advanced testicular cancer

PVB regimen, the combination of cisplatin (CDDP), vinblastine (VLB) and bleomycin (BLM), has improved the treatment results of testicular cancer patients. However, modification of doses and schedules were strongly related with the treatment results. We analyzed the relative dose intensity (RDI) of each patient undergoing PVB regimen, in relation to the chemotherapeutic effect. In addition, a role of granulocyte colony-stimulating factor (G-CSF) on dose intensity of PVB regimen was analyzed. During the period 1981-1992, 33 patients with testicular cancer were treated with PVB regimen. Among the 25 evaluable patients, 5 (20%) achieved a complete response (CR), 15 (60%) had a partial response (PR), and the overall response rate was 80%. The average 5-year survival rate of all cases was 78.4%. The RDI in CR and PR cases were significantly higher than nonresponders in BLM (0.89 for CR and 0.91 for PR against 0.32 for NC + PD) in the combination of the three drugs (1.05 for CR and 0.97 for PR against 0.69 for NC + PD). The standard-dose group (RDI > or = 0.9) had a higher survival rate than the modified-dose group (RDI < 0.9). The RDI of PVB regimen with administration of G-CSF was 0.98, whereas in the PVB-alone group it was 0.87 (p < 0.01). Our findings indicate that the RDI of BLM may be one of the most important factors in achieving a chemotherapeutic effect from the PVB regimen. G-CSF is useful for the completion of the schedule through the increase in dose intensification, and the prevention of leukocytopenia due to chemotherapy.

In vitro studies of release of adenine nucleotides and adenosine from rat vascular endothelium in response to alpha 1-adrenoceptor stimulation

1. Noradrenaline-induced release of endogenous adenine nucleotides (ATP, ADP, AMP) and adenosine from both rat caudal artery and thoracic aorta was characterized, using high-performance liquid chromatography with fluorescence detection. 2. Noradrenaline, in a concentration-dependent manner, increased the overflow of ATP and its metabolites from the caudal artery. The noradrenaline-induced release of adenine nucleotides and adenosine from the caudal artery was abolished by bunazosin, an alpha 1-adrenoceptor antagonist, but not by idazoxan, an alpha 2-adrenoceptor antagonist. Clonidine, an alpha 2-adrenoceptor agonist, contracted caudal artery smooth muscle but did not induce release of adenine nucleotides or adenosine. 3. Noradrenaline also significantly increased the overflow of ATP and its metabolites from the thoracic aorta in the rat; however, the amount of adenine nucleotides and adenosine released from the aorta was considerably less than that released from the caudal artery. 4. Noradrenaline significantly increased the overflow of ATP and its metabolites from cultured endothelial cells from the thoracic aorta and caudal artery. The amount released from the cultured endothelial cells from the thoracic aorta and caudal artery. The amount released from the cultured endothelial cells from the aorta was also much less than that from cultured endothelial cells from the caudal artery. In cultured smooth muscle cells from the caudal artery, a significant release of ATP or its metabolites was not observed. 5. These results suggest that there are vascular endothelial cells that are able to release ATP by an alpha 1-adrenoceptor-mediated mechanism, but that these cells are not homogeneously distributed in the vasculature.

Release of endogenous ATP from the caudal artery in rats with arteriosclerosis

Noradrenaline significantly increased (by a prazosin-sensitive mechanism) the overflow of ATP and its metabolites from the caudal arteries of rats treated with excess vitamin D2 and a high-cholesterol diet (arteriosclerotic rats), although the amount of the overflow was smaller than that in the normal rats. The arteries from the arteriosclerotic rats showed a marked increase in the calcium content and there was a significant negative correlation between the noradrenaline-induced overflow of ATP and the arterial calcium content. These findings indicate that ATP release from arteriosclerotic rat caudal arteries mediated by alpha 1-adrenoceptors is impaired in proportion to the extent of arterial calcification.

Transition of T cell receptor gamma/delta expressing double negative (CD4-/CD8-) lymphocytes after allogeneic bone marrow transplantation

We studied peripheral blood CD4-CD8- gamma/delta T cells in recipients of allogeneic marrow grafts, using three-color immunofluorescence and flow cytometry, and investigated changes in their numbers in relation to the administration of hematopoietic growth factors or chronic graft-versus-host disease (GVHD). In the early post-bone marrow transplantation (BMT) period, the relative and absolute numbers of peripheral CD4-CD8- gamma/delta T cells in 22 allogeneic marrow graft recipients in relation to the use of hematopoietic growth factors were studied. During the first 4 weeks, increased numbers of CD4-CD8- gamma/delta T cells were observed in recipients of either recombinant human granulocyte colony-stimulating factor (rhG-CSF) or granulocyte macrophage colony-stimulating factor (GM-CSF). However, 4-8 weeks after BMT, the number of these cells was similar in both groups whether or not growth factors had been administered. At a later stage after BMT (3-12 months), peripheral CD4-CD8- gamma/delta T cells from 43 allogeneic BMT recipients were studied. These cells were markedly decreased in patients with chronic GVHD, and this decrease correlated closely with the clinical signs of chronic GVHD. These results suggest that CD4-CD8- gamma/delta T cells may play an important role in the recovery of neutrophils associated with growth factors during the very early post-BMT period, and in the immunodeficient state of chronic GVHD at a later stage after BMT.

[Treatment of prostatic carcinoma with UFT and leucovorin--basic study using SRCA]

Combination effect of UFT and leucovorin against the rat prostatic carcinoma (R-3327) was evaluated by the subrenal capsular assay (SRCA) using nude mice. Anticancer effect of UFT was augmented by co-administration of both low and high dose leucovorin. These results suggest a clinical usefulness of UFT administration with leucovorin for the patients with hormonally refractory advanced prostatic carcinoma.