Fusion of the TEL gene on 12p13 to the AML1 gene on 21q22 in acute lymphoblastic leukemia

Chromosomal rearrangements involving band 12p13 are found in a wide variety of human leukemias but are particularly common in childhood acute lymphoblastic leukemia. The genes involved in these rearrangements, however, have not been identified. We now report the cloning of a t(12;21) translocation breakpoint involving 12p13 and 21q22 in two cases of childhood pre-B acute lymphoblastic leukemia, in which t(12;21) rearrangements were not initially apparent. The consequence of the translocation is fusion of the helix-loop-helix domain of TEL, an ETS-like putative transcription factor, to the DNA-binding and transactivation domains of the transcription factor AML1. These data show that TEL, previously shown to be fused to the platelet-derived growth factor receptor beta in chronic myelomonocytic leukemia, can be implicated in the pathogenesis of leukemia through its fusion to either a receptor tyrosine kinase or a transcription factor. The TEL-AML1 fusion also indicates that translocations affecting the AML1 gene can be associated with lymphoid, as well as myeloid, malignancy.

Heterogeneity of the angiogenic response induced in different normal adult tissues by vascular permeability factor/vascular endothelial growth factor

Vascular permeability factor/vascular endothelial growth factor (VPF/VEGF) is an angiogenic cytokine with potential for the treatment of tissue ischemia. To investigate the properties of the new blood vessels induced by VPF/VEGF, we injected an adenoviral vector engineered to express murine VPF/VEGF164 into several normal tissues of adult nude mice or rats. A dose-dependent angiogenic response was induced in all tissues studied but was more intense and persisted longer (months) in skin and fat than in heart or skeletal muscle (< or =3 weeks). The initial response (within 18 hours) was identical in all tissues studied and was characterized by microvascular hyperpermeability, edema, deposition of an extravascular fibrin gel, and the formation of enlarged, thin-walled pericyte-poor vessels ("mother" vessels). Mother vessels developed from preexisting microvessels after pericyte detachment and basement membrane degradation. Mother vessels were transient structures that evolved variably in different tissues into smaller daughter vessels, disorganized vessel tangles (glomeruloid bodies), and medium-sized muscular arteries and veins. Vascular structures closely resembling mother vessels and each mother vessel derivative have been observed in benign and malignant tumors, in other examples of pathological and physiological angiogenesis, and in vascular malformations. Together these data suggest that VPF/VEGF has a role in the pathogenesis of these entities. They also indicate that the angiogenic response induced by VPF/VEGF is heterogeneous and tissue specific. Finally, the muscular vessels that developed from mother vessels in skin and perimuscle fat have the structure of collaterals and could be useful clinically in the relief of tissue ischemia.

Surgical treatment of obesity and its effect on diabetes: 10-y follow-up

Since 1980 we have performed the identical Greenville gastric bypass (GGB) procedure on 479 morbidly obese patients with an acceptable morbidity and a mortality rate of 1.2%. The weight loss in the series was well maintained over the follow-up period of 10 y. The GGB can control non-insulin-dependent diabetes mellitus (NIDDM) in most patients. The group of 479 patients included 101 (21%) with NIDDM and another 62 (13%) who were glucose impaired. Of these 163 individuals, 141 reverted to normal and only 22 (5%) remained with inadequate control of their carbohydrate metabolism. Those patients who were older or whose diabetes was of longer duration were less likely to revert to normal values. The gastric bypass operation is an effective approach for the treatment of morbid obesity. Along with its control of weight, the operation also controls the hyperglycemia, hyperinsulinemia, and insulin resistance of the majority of patients with either glucose impairment or frank NIDDM.

A genetic map in the Mimulus guttatus species complex reveals transmission ratio distortion due to heterospecific interactions

As part of a study of the genetics of floral adaptation and speciation in the Mimulus guttatus species complex, we constructed a genetic linkage map of an interspecific cross between M. guttatus and M. nasutus. We genotyped an F(2) mapping population (N = 526) at 255 AFLP, microsatellite, and gene-based markers and derived a framework map through repeated rounds of ordering and marker elimination. The final framework map consists of 174 marker loci on 14 linkage groups with a total map length of 1780 cM Kosambi. Genome length estimates (2011-2096 cM) indicate that this map provides thorough coverage of the hybrid genome, an important consideration for QTL mapping. Nearly half of the markers in the full data set (49%) and on the framework map (48%) exhibited significant transmission ratio distortion (alpha = 0.05). We localized a minimum of 11 transmission ratio distorting loci (TRDLs) throughout the genome, 9 of which generate an excess of M. guttatus alleles and a deficit of M. nasutus alleles. This pattern indicates that the transmission ratio distortion results from particular interactions between the heterospecific genomes and suggests that substantial genetic divergence has occurred between these Mimulus species. We discuss possible causes of the unequal representation of parental genomes in the F(2) generation.

Simultaneous measurement of six cytokines in a single sample of human tears using microparticle-based flow cytometry: allergics vs. non-allergics

Tears play an essential role in maintaining corneal and conjunctival integrity by providing a tightly regulated, optimal extracellular environment critical to its numerous functions, which include anti-microbial defense, wound healing and inflammatory responses such as allergies. Elevated levels of inflammatory cytokines have been reported in tears from various ocular disease states. Characterization of tear cytokines has been limited by the small volume (microliter amounts) attainable. This limitation was addressed with the newly developed Becton Dickinson Cytometric Bead Array (CBA), which combines the principles of the "sandwich" immunoassay with the capability of flow cytometry for simultaneous measurement of the characteristics of multiple particles. This technique allows determination of six human cytokine (IFNgamma, TNFalpha, IL-2, IL-4, IL-5, IL-10) concentrations simultaneously in a single tear sample. Tears were collected from the inferior fornix of non-allergic (n=7) and allergic (n=9) donors. Each tear sample or cytokine standard was incubated with a mixture of capture Ab-bead reagent and detector Ab-phycoerythrin (PE) reagent, and analyzed using flow cytometry. All six cytokines were detectable in both non-allergic and allergic tears. Tears from allergic donors contained significantly less IL-10 (p=0.035), and had significant increases in the ratios of TNFalpha/IFNgamma, IL-5/IFNgamma and IL-5/IL-10 (p=0.0008, 0.0124 and 0.011, respectively). The small volume required (5-10 microl/test) by the Cytometric Bead Array allows measurement of all six cytokines from a single collection of tears. This decreases collection time, minimizing the confounding effect of stimulation on cytokine concentration in tears, as well as allowing calculation of cytokine ratios.

Trends in incidence of thick, thin and in situ melanoma in Europe

BACKGROUND

We analysed trends in incidence for in situ and invasive melanoma in some European countries during the period 1995-2012, stratifying for lesion thickness.

MATERIAL AND METHODS

Individual anonymised data from population-based European cancer registries (CRs) were collected and combined in a common database, including information on age, sex, year of diagnosis, histological type, tumour location, behaviour (invasive, in situ) and lesion thickness. Mortality data were retrieved from the publicly available World Health Organization database.

RESULTS

Our database covered a population of over 117 million inhabitants and included about 415,000 skin lesions, recorded by 18 European CRs (7 of them with national coverage). During the 1995-2012 period, we observed a statistically significant increase in incidence for both invasive (average annual percent change (AAPC) 4.0% men; 3.0% women) and in situ (AAPC 7.7% men; 6.2% women) cases.

DISCUSSION

The increase in invasive lesions seemed mainly driven by thin melanomas (AAPC 10% men; 8.3% women). The incidence of thick melanomas also increased, although more slowly in recent years. Correction for lesions of unknown thickness enhanced the differences between thin and thick cases and flattened the trends. Incidence trends varied considerably across registries, but only Netherlands presented a marked increase above the boundaries of a funnel plot that weighted estimates by their precision. Mortality from invasive melanoma has continued to increase in Norway, Iceland (but only for elder people), the Netherlands and Slovenia.

An energy supply network of nutrient absorption coordinated by calcium and T1R taste receptors in rat small intestine

T1R taste receptors are present throughout the gastrointestinal tract. Glucose absorption comprises active absorption via SGLT1 and facilitated absorption via GLUT2 in the apical membrane. Trafficking of apical GLUT2 is rapidly up-regulated by glucose and artificial sweeteners, which act through T1R2 + T1R3/alpha-gustducin to activate PLC beta2 and PKC betaII. We therefore investigated whether non-sugar nutrients are regulated by taste receptors using perfused rat jejunum in vivo. Under different conditions, we observed a Ca(2+)-dependent reciprocal relationship between the H(+)/oligopeptide transporter PepT1 and apical GLUT2, reflecting the fact that trafficking of PepT1 and GLUT2 to the apical membrane is inhibited and activated by PKC betaII, respectively. Addition of L-glutamate or sucralose to a perfusate containing low glucose (20 mM) each activated PKC betaII and decreased apical PepT1 levels and absorption of the hydrolysis-resistant dipeptide L-Phe(PsiS)-L-Ala (1 mM), while increasing apical GLUT2 and glucose absorption within minutes. Switching perfusion from mannitol to glucose (75 mM) exerted similar effects. c-glutamate induced rapid GPCR internalization of T1R1, T1R3 and transducin, whereas sucralose internalized T1R2, T1R3 and alpha-gustducin. We conclude that L-glutamate acts via amino acid and glucose via sweet taste receptors to coordinate regulation of PepT1 and apical GLUT2 reciprocally through a common enterocytic pool of PKC betaII. These data suggest the existence of a wider Ca(2+) and taste receptor-coordinated transport network incorporating other nutrients and/or other stimuli capable of activating PKC betaII and additional transporters, such as the aspartate/glutamate transporter, EAAC1, whose level was doubled by L-glutamate. The network may control energy supply.

Is type II diabetes mellitus (NIDDM) a surgical disease?

Since February 1, 1980, 515 morbidly obese patients have undergone the Greenville gastric bypass (GGB) operation. Of these, 212 (41.2%) were euglycemic, 288 (55.9%) were either diabetic or had glucose intolerance, and 15 (2.9%) were unable to complete the evaluation. After the operation, only 30 (5.8%) patients remained diabetic (and 20 of these improved), 457 (88.7%) became and have remained euglycemic, and inadequate data prevented classification of the other 28 (5.4%). The patients who failed to return to normal glucose values were older and their diabetes was of longer duration than those who did. The effect of the GGB was not only limited to the correction of abnormal glucose levels. The GGB also corrected the abnormal levels of fasting insulin and glycosylated hemoglobin in a cohort of 52 consecutive severely obese patients with non-insulin-dependent diabetes. The GGB effectively controls weight. If morbid obesity is defined as 100 pounds over ideal body weight, 89% of the patients are no longer "morbidly" obese within 2 years. In most patients, the control of the weight has been well maintained during the 11 years of follow-up; most of the upward creep in weight of 20.8% between 24 and 132 months was from the 49 (9.5%) patients who had staple line breakdowns between the large and small gastric pouches. Non-insulin-dependent diabetes, previously considered a chronic unrelenting disease, can be controlled in the severely obese by the gastric bypass. Whether the correction of glucose metabolism affects the complications of diabetes is unknown. Whether the gastric bypass should be considered for patients with advanced non-insulin-dependent diabetes but who are not severely obese deserves consideration. The GGB has an unacceptably high rate of staple line failure. Accordingly, the authors have recently changed their procedure to one that divides the stomach rather than partitions it with staples.

Epidemiology of basal and cutaneous squamous cell carcinoma in the U.K. 2013-15: a cohort study

BACKGROUND

Basal cell carcinoma (BCC) and cutaneous squamous cell carcinoma (cSCC), together known as keratinocyte cancers (KCs), are the commonest cancer in white ethnic populations. Recent improvements to registry data collection in England has allowed more accurate analysis of the epidemiology of BCC and cSCC and for the first time we are able to provide an accurate (representative) tumour burden for KC in the U.K.

OBJECTIVES

To estimate the incidence of BCC and cSCC in the U.K.

METHODS

A cohort of patients with KCs between 2013 and 2015 were identified using linkage to diagnostic codes derived from pathology reports collected into the national cancer registry. Data from England's cancer registry were combined with data from Scotland, Northern Ireland and Wales. European age-standardized incidence rates (EASRs) of the first BCC and cSCC per patient per annum (PPPA) were calculated.

RESULTS

In the U.K, the EASR of the first BCC and cSCC PPPA in 2013-15 were 285 and 77 per 100 000 person years, respectively (211 120 KCs total in 2015). The mean annual percentage increase was 5% between 2013 and 2015 for both BCC and cSCC. By counting the first KC PPPA, we include an additional 51% KCs compared with the previous reporting technique which counts only the first BCC and cSCC in a patient's lifetime, yet it represents a probable underestimation of 5-11% of the true tumour count.

CONCLUSIONS

Based on an improved methodology, a more representative incidence of KC is presented, which is essential to healthcare planning and will lead to improved understanding of the epidemiology of KC. What's already known about this topic? Keratinocyte cancers (KCs) are the most common cancers affecting white ethnic populations. The incidence of basal cell carcinoma (BCC) and cutaneous squamous cell carcinoma (cSCC) is increasing worldwide including the U.K., most commonly in elderly male Caucasian patients. These cancers are traditionally substantially underreported and frequently excluded from national cancer statistics. What does this study add? Using improved data collection methods in England and validated tumour-reporting techniques, we report the most accurate BCC and cSCC incidence data for the U.K. ever published. Identifying the first BCC and cSCC per patient per annum, the incidence of BCC and cSCC in the U.K. (excluding Wales) was 285 and 77 per 100 000 person years, respectively, between 2013 and 2015, with more than 210 000 KCs in the U.K. in 2015.

Interleukin-10 secretion differentiates dendritic cells from human liver and skin

Liver dendritic cells (DCs), which may orchestrate the liver's unique immunoregulatory functions, remain poorly characterized. We used a technique of overnight migration from pieces of normal human liver and skin to obtain tissue-derived DCs with minimal culture and no additional cytokine treatment. Liver and skin DCs had a monocyte-like morphology and a partially mature phenotype, expressing myeloid markers, MHCII, and co-stimulatory molecules; but only the skin DCs contained a population of CD1a+ cells. Overnight-migrated liver DCs activated naïve cord blood T cells efficiently. Liver DCs produced interleukin (IL)-10 whereas skin DCs failed to secrete IL-10 even after stimulation and neither skin nor liver-derived DCs secreted significant amounts of IL-12p70. Compared with skin DCs, liver DCs were less effective at stimulating T-cell proliferation and stimulated T cells to produce IL-10 and IL-4 whereas skin DCs were more potent stimulators of interferon-gamma and IL-4. Monocyte-derived DCs were down-regulated after culture with liver-conditioned media, suggesting that local microenvironmental factors may be important. Thus we show for the first time clear tissue-specific differences in nonlymphoid DCs. Although it is not possible to conclude from our data whether liver DCs are more regulatory, or skin DCs more proimmunogenic, the ability of liver DCs to secrete IL-10 may be important for regulating local immune responses within the liver in the face of constant exposure to gut antigens.

Ultrastructural evidence for piecemeal and anaphylactic degranulation of human gut mucosal mast cells in vivo

One hundred and seventeen coded intestinal biopsies were examined by electron microscopy and evaluated for morphological evidence of mast cell and basophil secretion in situ. Sixty percent of the biopsies had evidence of secretion. Mast cell secretion was evident in control biopsies, many of which were obtained from uninvolved tissues of patients with inflammatory bowel disease. Biopsies of inflamed continent pouches from ulcerative colitis (UC) patients showed more mast cell secretion than noninflamed UC pouch biopsies. This evidence of mast cell secretion supports recent work that documents high constitutive levels of histamine in jejunal fluids of Crohn's disease patients and suggests a proinflammatory role for mast cells in inflammation associated with pouchitis.

Undifferentiated sarcoma of the kidney: a tumor of childhood with histopathologic and clinical characteristics distinct from Wilms' tumor

The pathological and clinical features of 123 patients with Wilms' tumor diagnosed between 1961 and 1977 were analyzed. A subgroup of nine patients with distinctive histology characterized by the presence of exclusively sarcomatous elements was identified. These patients were indistinguishable clinically from the other patients with Wilms' tumor and were treated as Wilms' tumor. The rate of recurrence in this group of sarcomatous Wilms' tumor was very high (7/9) and long-term disease-free survival correspondingly low )3/9 free of disease from 15 months to nine years) when compared to the patients with classical Wilms' tumor (50% recurrence rate and 71% currently free of disease). In addition, patients with metastases (seven of seven patients with recurrence had skeletal involvement as contrasted to one of 50 patients with metastatic classical Wilms' tumor). We conclude that the "sarcomatous Wilms' tumor" represents a distinct clinicopathological entity identifiable morphologically at diagnosis, best described as renal sarcoma and that in the future optimal treatment of this disease may vary somewhat from the treatment of classical Wilms' tumor.

Thromboxane synthesis by sources other than platelets in association with complement-induced pulmonary leukostasis and pulmonary hypertension in sheep

Infusion into sheep of plasma containing zymosan-activated complement produces leukopenia, pulmonary leukostasis, and pulmonary artery hypertension. We previously demonstrated a close relationship between the pulmonary vascular response and elevations of plasma thromboxane. We have investigated the source of thromboxane synthesis in this model. Plasma containing zymosan-activated complement added to whole blood did not stimulate thromboxane synthesis. This observation suggested that leukocytes do not synthesize thromboxane directly in response to complement added to whole blood did not stimulate thromboxane synthesis. This observation suggested that leukocytes do not synthesize thromboxane directly in response to complement. Sheep rendered severely thrombocytopenic by the administration of antiplatelet serum responded to complement infusion in the usual way. Pretreatment with aspirin (10 mg/kg) protected sheep against the pulmonary vascular response and completely blocked thromboxane synthesis. Transfusion of functional platelets did not restore these responses. Twenty-four hours after aspirin treatment, in vivo thromboxane synthesis was significantly greater than platelet thromboxane synthesis in vitro. Thromboxane is synthesized by a tissue which recovers cyclooxygenase enzyme activity at a rate that is more rapid than platelet turnover. Sheep lung synthesizes thromboxane actively in vitro. It is postulated that leukocytes exposed to activated complement components damage pulmonary vascular endothelial cells and stimulate synthesis of thromboxane A2 which causes pulmonary vasoconstriction.

Gastrogastric fistulas. A complication of divided gastric bypass surgery

OBJECTIVE

This report warns that gastrogastric fistulas may follow the division of the stomach in bariatric surgery.

SUMMARY BACKGROUND DATA

Although surgery is the most effective therapy for morbid obesity, the procedures are still undergoing evolution. One of the key elements in bariatric surgery is the partition of the stomach to develop a much smaller reservoir. The partition has been done with single layers of staples with almost universal failure and with double layers of staples with a failure rate of 11.8% when observed for a 12-year follow-up.

METHODS

This report details the experience with a series of 100 consecutive patients in whom the partition was created by dividing the stomach.

RESULTS

The course of six patients was complicated by gastrogastric fistulas. One of the patients had the gastric bypass as the initial bariatric operation; in the other five, the gastric bypasses were carried out to revise failed staple lines. Although one of the patients required drainage for a subphrenic abscess, two had only self-limited signs of infection. In the remaining three patients, there was no evidence of any complication.

CONCLUSION

Gastrogastric fistulas followed division of the stomach in 6% of our gastric bypass operations. Methods for avoiding this complication include oversewing staple lines, using strong bites of tissue during the anastomosis, avoiding obstruction of the Roux-en-Y jejunal segment, and testing of the integrity of the anastomosis with methylene blue dyes. The ideal method for partition of the stomach remains to be developed.

Prevalence and age of onset of Parkinson's disease in Cardiff: a community based cross sectional study and meta-analysis

BACKGROUND

Previous prevalence studies of Parkinson's disease (PD) in the UK have spanned a 40 year period and have predominantly been in the North of the country. These have presented rates by current age but have not examined this by age at disease onset.

METHODS

A community based prevalence study was undertaken which attempted to identify all clinically diagnosed cases of PD from primary and secondary care for the city of Cardiff, Wales, UK. A meta-analysis of all past studies in the UK, including our own, was also undertaken.

RESULTS

Overall, 380 cases of PD were identified from a population of 292 637 residents, giving a crude prevalence rate of 130 per 100 000 (95% CI 117 to 144) and an age standardised rate of 142 per 100 000 (95% CI 128 156), standardised to the 1997 England and Wales population. Our prevalence rates were very similar to the weighted average of previous UK studies although there was evidence of between study heterogeneity (p = 0.0006). 5.4% and 31.2% of prevalent PD patients had their disease onset below the age of 50 or 65 years, respectively.

CONCLUSIONS

The data suggest that there are no major geographical variations in the prevalence of PD in the UK and that the age adjusted prevalence rate has remained relatively stable over the past 40 years. Although PD risk is far greater in older subjects, patients with young onset are not that uncommon in the community, and health and social care provision should reflect their needs.

Ultrastructural immunogold localization of prostaglandin endoperoxide synthase (cyclooxygenase) to non-membrane-bound cytoplasmic lipid bodies in human lung mast cells, alveolar macrophages, type II pneumocytes, and neutrophils

Lipid bodies are non-membrane-bound, lipid-rich cytoplasmic inclusions that occur in many mammalian cell types. Because lipid bodies are more prominent in cells associated with inflammation and are repositories of arachidonyl-phospholipids, a role for lipid bodies in the oxidative metabolism of arachidonic acid to form eicosanoids has been suggested. To evaluate further whether lipid bodies, in addition to serving as non-membranous sources of substrate arachidonate, are involved in eicosanoid formation, we used cells isolated from human lung to investigate the intracellular localization of prostaglandin endoperoxide (PGH) synthase (cyclooxygenase), the key initial, rate-limiting enzyme in the formation of prostaglandins and thromboxanes. Isolated lung cells containing a mixture of mast cells, alveolar macrophages, Type II alveolar pneumocytes, and neutrophils from short-term cultures were fixed in suspension in a dilute aldehyde mixture, post-fixed in osmium tetroxide, stained en bloc with uranyl acetate, dehydrated in a graded series of alcohols, and embedded in Epon. A post-embedding immunogold procedure was used with a primary PGH synthase monoclonal antibody and 20-nm gold-conjugated secondary antibody to demonstrate enzyme locations. Specificity controls were also done. We found PGH synthase in lipid bodies of human lung mast cells, alveolar macrophages, Type II alveolar pneumocytes, and neutrophils. Specific secretory and lysosomal granules and plasma membranes did not express PGH synthase. Specificity controls, including omission of the primary antibody or substitution with an irrelevant antibody, were negative. Absorption of the specific PGH synthase antibody with purified solid-phase PGH synthase resulted in a marked reduction of label in lipid bodies of all four cell types. These findings establish the presence of PGH synthase in lipid bodies of human lung mast cells, alveolar macrophages, Type II alveolar pneumocytes, and neutrophils and, in concert with previous studies, suggest that these cytoplasmic lipid-rich organelles may be non-membrane sites of eicosanoid formation.

Predictors of operative death after oesophagectomy for carcinoma

BACKGROUND

Oesophagectomy for carcinoma provides a chance of cure but carries significant risk. This study defined risk factors for death after oesophageal resection for malignant disease.

METHODS

Between 1990 and 2003, 773 oesophagectomies for oesophageal cancer were performed. Continuous variables were categorized into quartiles for analysis. Predictors of operative mortality were identified by univariate and multiple logistic regression analysis.

RESULTS

The operative mortality rate was 4.8 per cent (37 of 773). In univariate analysis, advanced age, reduced forced expiratory volume in 1 s (FEV1), reduced forced vital capacity, presence of diabetes and tumour located in the upper third of the oesophagus were associated with a higher mortality rate. Multivariate analysis identified age (highest relative to lowest quartile, odds ratio (OR) 4.87 (95 per cent confidence interval (c.i.) 1.35 to 17.55); P = 0.009), tumour position (upper third relative to other locations, OR 4.23 (95 per cent c.i. 1.06 to 16.86); P = 0.041) and FEV1 (lowest relative to highest quartile, OR 4.72 (95 per cent c.i. 1.01 to 21.99); P = 0.018) as independent predictors of death.

CONCLUSION

Advanced age, impaired preoperative respiratory function and a tumour high in the oesophagus are associated with a significantly increased risk of death after oesophagectomy for carcinoma.

The preservation of nerve cells in rat neostriatal slices maintained in vitro: a morphological study

The in vitro preservation of neurons in 300 micron thin neostriatal slices, which are routinely used for electrophysiological studies, was examined by light and electron microscopy and was compared to 700 micron thick neostriatal slices. The thin slices displayed well-preserved cells after up to 5 h of incubation. This finding correlated well with whether electrical activity could be recorded. In cross-section, the thin slices consisted of three layers: the inner layer contained many intact cells (80%) and was sandwiched between the outer layers where deteriorating cells predominated. In contrast to the thin slices, the thick slices (700 micron) displayed no layering of intact cells in cross-section. Instead, the majority of cells throughout these thick slices was swollen (98%), with only small patches of intact cells. Two types of deteriorating cells were apparent: swollen cells and dark (pycnotic) cells. The proportion of swollen cells increased with incubation time. In the thin slices this swelling occurred in the outer layers with the middle layer of intact cells remaining relatively unchanged over long incubation periods, whereas all cells in the thick slices were swollen after 2 h of incubation. Dark cells were localized to the outer portion of both slices and the number of such dark cells did not change with incubation time.

Effects of calcium, calcium channel blockers and Bay K 8644 on contractions induced by muscarinic receptor stimulation of isolated bladder muscle from rabbit and man

In isolated bladder smooth muscle from both rabbit and man, carbachol-induced contractions were reduced by the calcium channel blocker nifedipine, whereas the calcium channel promotor Bay K 8644 had no effect. In nominally calcium-free medium containing 10(-4) M EGTA, carbachol-induced contractions were reduced by 69% (rabbit) and 87% (man). These contractions were abolished by nifedipine, whereas Bay K 8644 significantly increased their amplitude, in rabbit preparations almost to control level. Electrical field stimulation produced contractions which could be suppressed by scopolamine by about 50% (rabbit) and more than 90% (man). These contractions were abolished by calcium-free medium (10(-4) M EGTA), suppressed by nifedipine, but significantly enhanced by Bay K 8644. The depressant effects of nifedipine, verapamil and diltiazem were reversed by Bay K 8644. The calcium channel blockers relaxed K+-induced contractions to base line, and this action was counteracted by Bay K 8644, less effectively when relaxations were induced by diltiazem. It is concluded that contractions produced by muscarinic receptor stimulation are primarily dependent on calcium bound to the outside of the membrane of the smooth muscle, and/or coming from the extracellular medium. Electrically evoked, scopolamine sensitive contractions seem to be mediated by a mechanism different from that of contractions produced by exogenously added muscarinic receptor agonist. The present data support the view that combined blockade of muscarinic receptors and calcium channels is an effective way of inhibiting bladder contractions in both rabbit and man.