[Significance of rectal contractions during multichannel urodynamic study]

BACKGROUND

The influence of rectal contractions on urination was examined using multichannel urodynamic study.

METHODS

We reviewed a total of 246 consecutive urodynamic studies. Each study consisted of a uroflow measurement and multi-channel urodynamic study, evaluating total vesical pressure, abdominal (rectal) pressure, subtracted detrusor pressure and perianal electromyography. Rectal contractions were defined as periodic fluctuations over 5 cmH2O in abdominal pressure detected by a rectal balloon catheter. No relationship of these contractions with cough and breathing was observed.

RESULTS

Of the 246 patients, 17 (6.9%) had a positive study for rectal contractions. The patients, who had positive rectal contractions, averaged 70-year-old were older than negative subjects averaged 62-year-old. In multichannel urodynamics, the flow rate was significantly decreased, and electromyographic activity was increased at the moment of each rectal contractions.

CONCLUSIONS

The rectal contractions are not artifactual and may be regarded as one of causes responsible for urinary difficulty in the elderly.

Gracilis urethral myoplasty: preliminary experience using an autologous urinary sphincter for post-prostatectomy incontinence

PURPOSE

We investigated the effect of a neurovascular intact gracilis muscle urethral wrap to restore urinary continence in men with severe stress urinary incontinence after radical retropubic prostatectomy.

MATERIALS AND METHODS

Three men with stress incontinence after radical retropubic prostatectomy and external beam radiation therapy for adenocarcinoma of the prostate underwent gracilis urethral myoplasty. Video urodynamic evaluation and cystourethroscopy revealed Valsalva leak point pressure of less than 40 cm. water and a damaged urinary sphincter mechanism in all 3 patients. One man underwent concomitant ileocystoplasty.

RESULTS

At 6 to 24-month followup all patients reported improved continence. Mean Valsalva leak point pressure increased from 26.3 +/- 3.2 cm. water before to 83.0 +/- 32.1 cm. water after surgery. The gracilis muscle urethral wrap did not have a deleterious effect on erectile function or ambulation. Complications included 1 wound infection.

CONCLUSIONS

An autologous gracilis muscle urinary neosphincter can be constructed in the bulbous urethra in a fashion similar to that of the artificial urinary sphincter with encouraging results in this preliminary series. The gracilis neosphincter may be an alternative to the artificial sphincter, especially in patients at higher risk for complications, such as after radiation and cryotherapy.

Fibroblasts of spinal ligaments pathologically differentiate into chondrocytes induced by recombinant human bone morphogenetic protein-2: morphological examinations for ossification of spinal ligaments

To elucidate the process of ossification in spinal ligaments, an aqueous solution containing recombinant human bone morphogenetic protein (BMP)-2 (40 micrograms/100 microL) was injected into murine ligamenta flava, and the ossification process was analyzed morphologically. In the control group, the solution administered lacked the protein; these flattened ligamentous fibroblasts possessing BMP receptors type IA and type II existed among type I collagen bundles. In the week immediately following the injection of BMP-2, ligamentous fibroblasts began to proliferate, differentiating into alkaline phosphatase-positive chondrocytes surrounded by an extracellular matrix composed of type I and II collagen. By the second week, differentiated chondrocytes of various stages were observed in type II collagen-rich matrix. These chondrocytes showed an abundance of BMP receptors type IA and II. The pathologically induced cartilage was resorbed by chondroclasts, permitting migration of blood vessels and osteogenic cells, as well as providing a site for endochondral ossification. By the third week, BMP-induced ossification had compressed the spinal cord, and by the sixth week, the ligamentous tissue had been almost completely replaced by bone. Ligamentous fibroblasts appeared to possess BMP receptors, as well as the potentiality to differentiate into chondrocytes. BMP receptors were upregulated during chondrification of ligamentous fibroblasts induced by exogenous BMP-2, suggesting that BMPs may play an important role in ossification of spinal ligaments.

Chronic loss of glucocorticoids following adrenalectomy down-regulates the expression of glucocorticoid receptor mRNA in the rat forebrain

In the negative feedback model, loss of endogenous glucocorticoids up-regulates the expression of glucocorticoid receptor mRNA. To elucidate further the effect of chronic lack of glucocorticoids on the expression of glucocorticoid receptor mRNA and protein, in situ hybridization and immunohistochemical methods were used to examine the long-term alteration of glucocorticoid receptor mRNA and its immunoreactivity in the forebrain of adrenalectomized rats. Constant lack of glucocorticoids resulted in marked decrease in the expression of glucocorticoid receptor mRNA and disappearance of glucocorticoid receptor immunoreactivity in many forebrain structures. In particular, in the suprapyramidal blade of the hippocampal granule cell layer and cerebral cortex, many cells showed almost no glucocorticoid receptor mRNA signals. These results suggest that long-term loss of endogenous glucocorticoids down-regulates the levels of glucocorticoid receptor mRNA, leading to reduction in the synthesis of glucocorticoid receptors in the rat forebrain. Therefore, the presence of endogenous glucocorticoids is vital to the continued expression of glucocorticoid receptor mRNA.

[A case of juvenile Huntington's disease presenting dystonia and confirmed by DNA analysis]

We reported a 13-year-old boy with juvenile Huntington disease diagnosed by DNA analysis. Symptoms started with dysarthria at 6 years of age, which was followed by progressive dysgraphia and gait disturbance due to dystonia from 7 years, and by epileptic seizures from 12 years. Magnetic resonance imaging revealed atrophy of the bilateral caudate nuclei and T2- and proton-weighted high intensity area in both putamina. The CAG (cytosine-adenine-guanine) trinucleotide repeat on chromosome 4 p16 was markedly expanded to 81. For a child with dystonia with mental deterioration, juvenile Huntington disease should be considered in the differential diagnosis.

Saccharated ferric oxide (SFO)-induced osteomalacia: in vitro inhibition by SFO of bone formation and 1,25-dihydroxy-vitamin D production in renal tubules

A 60-year-old man with portal hypertensive gastropathy due to type C liver cirrhosis developed severe bone pains, marked hypophosphatemia with inappropriately increased urinary excretion of phosphate (%TRP; 9.6%), and hyperalkaline phosphatasia, after intravenous administration of saccharated ferric oxide (SFO) at a dose of 80-240 mg/week over a period of more than 5 years. The total iron infused was estimated to be more than 25 g. On a diagnosis of SFO-induced osteomalacia, the infusion of iron was immediately discontinued, and phosphate and vitamin D2 (1000 IU/day) were administered. Serum levels of 25-OHD2 increased after 1 week, whereas levels of 1,25-(OH)2D2 did not increase until 3 months later, accompanied by improvement of renal tubular reabsorption of phosphate and gradual improvement of the bone pains. The patient has been doing well for the last 2 years, with normal serum levels of phosphate, calcium, and alkaline phosphatase, without any supplementation of phosphate, vitamin D, or iron-containing agents. In primary culture of neonatal mouse renal tubules, in which 1,25-(OH)2D3 was produced from 25-OHD3 in response to PTH, SFO significantly inhibited PTH-induced production of 1,25-(OH)2D3 at 30 mumol/L, which is attainable in the urine of patients receiving a therapeutic intravenous dose of SFO. Furthermore, SFO decreased the calcium content and inhibited 45Ca incorporation in cultured fetal mouse parietal bones at 3 mumol/L. Such SFO concentration may be transiently observed in the plasma of patients receiving excessive intravenous doses of SFO for a prolonged period. These in vitro findings together with the clinical observations suggest that SFO, after filtration through the glomerulus and reabsorption in the proximal renal tubules, impaired proximal renal tubular function, such as tubular reabsorption of phosphate and 1 alpha-hydroxylase activity, leading to hypophosphatemic osteomalacia. Furthermore, it is highly likely that SFO in the peripheral blood, when transferrin is saturated with iron, may impair bone formation and aggravate osteomalacia. Although SFO-induced osteomalacia is reversible simply by discontinuation of the agent, excessive and prolonged administration of SFO should be avoided.

Generation and characterization of mouse monoclonal antibodies specific for N-linked neutral oligosaccharides of glycoproteins

We generated four monoclonal antibodies (MAbs) specific for asparagine-linked neutral oligosaccharides of glycoproteins by immunizing mice with neoglycolipids, which were derived from glycoproteins by conjugation to phosphatidylethanolamine dipalmitoyl. The binding specificity of these MAbs was determined by an enzyme-linked immunosorbent assay and immunostaining on thin-layer chromatography. The four MAbs designated OMB3, OMB4, OMR5, and OMR6 reacted strongly with the neoglycolipids, Gal beta1-4GlcNAc beta1-2Man alpha1-6(Gal beta1-4GlcNAc beta1-2Man alpha1-3)Man beta1-4GlcNAc-PD, GlcNAc beta1-2Man alpha1-6(GlcNAc beta1-2Man alpha1-3)(GlcNAc beta1-4)Man beta1-4GlcNAc beta1-4GlcNAc-PD, Man alpha1-6Man beta1-4GlcNAc beta1-4(Fuc alpha1-6)GlcNAc-PD, and Man alpha1-3Man beta1-4GlcNAc-PD, respectively, that were used as immunogens. All of these MAbs exhibited a high binding specificity. The epitopes of the MAbs OMB3 and OMB4 were suggested to be nonreducing terminal trisaccharides, Gal beta1-4GlcNAc beta1-2Man-, and nonreducing beta-GlcNAc residues, respectively. MAbs OMR5 and OMR6 showed a highly restricted binding specificity, reacting only with the immunizing neoglycolipids. Subsequently, MAbs OMB3 and OMB4 were shown to react strongly with asialo-alpha1-acid-glycoprotein and asialo-agalacto-alpha1-acid-glycoprotein, respectively, by Western blotting. Furthermore, it was shown that these MAbs reacted specifically with the epitope on Chinese hamster ovary cells by an immunofluorescence technique. MAb OMB4 was also shown to detect the accumulated oligosaccharides with nonreducing terminal beta-GlcNAc residues as granular inclusions in the cultured fibroblasts from a classical Sandhoff disease patient.

The in vivo time course for elimination of adrenalectomy-induced apoptotic profiles from the granule cell layer of the rat hippocampus

Although apoptotic cellular degeneration has been reported to be extremely rapid with the use of in vitro models, the time needed to clear apoptotic neurons in the in vivo brain is unknown. In this study we used a simple morphological approach to solve this problem. Four days after adrenalectomy (ADX), all of the operated rats morphologically displayed hippocampal granule cell apoptosis that was prevented completely by corticosterone replacement immediately after ADX. Therefore, we intravenously injected the rats with corticosterone 4 d after ADX and subsequently maintained them on corticosterone replacement in saline drinking water. This corticosterone replacement could protect healthy granule cells promptly and continuously against hormone-deficient apoptosis, because the normal glucocorticoid receptor immunoreactivity within the granule cell nuclei, which disappeared after ADX, was identified 1 hr after corticosterone replacement was started, and this effect persisted for several days. However, this corticosterone treatment could not prevent the irreversible apoptosis of the already degenerated granule cells at various stages of the same progressive apoptotic process. Then we successively traced the disappearance of apoptotic granule cells throughout the hippocampus at different time points by Nissl and silver staining. Given that the apoptotic cells at the earliest stage of the degenerating process when the ADX rats received corticosterone injection were the last to disappear, the period from corticosterone injection until the disappearance of the last degenerating debris of apoptotic cells was taken to represent the time course for elimination of apoptotic neurons in vivo. We discovered that the elimination of apoptotic granule cells took 72 hr.

Gangliosides involved in activation of rat T lineage cells

Gangliosides have long been known to be involved in T-cell activation. In our previous studies, a unique GMlb-derived ganglioside, GD1c(NeuGc,NeuGc), was shown to be the predominant ganglioside in rat thymocytes and T-cells. Upon the activation of the thymocytes, the amount of GD1c(NeuGc,NeuGc) increases remarkably, and additionally a novel species of GD1b, GD1b(NeuGc,NeuGc), appears as the other major ganglioside (Nohara, et al. (1993) J. Biol. Chem. 268, 24997-25000). In the present study, monoclonal antibodies (MAbs) against these two gangliosides have been generated. The MAb AC1 established by immunizing mice with purified GD1c(NeuGc,NeuGc) reacted strongly with GD1c(NeuGc,NeuGc) and weakly with GD1b(NeuGc,NeuGc) by enzyme-linked immunosorbent assay (ELISA). The other MAb AB1 obtained by immunization with GD1b(NeuGc,NeuGc) showed a strong binding activity to GD1b(NeuGc,NeuGc) and no reactivity to GDlc(NeuGc,NeuGc) by ELISA. Flow cytometry analyses using these MAbs have revealed that an AC1-positive subset exists in a portion of resting CD4+CD8- thymocytes and CD4+ splenic T-cells. When the thymocytes were activated with 12-O-tetradecanoylpholbol-13-acetate (TPA) and calcium ionophore A23187, the proportion of AC1+ cells increased remarkably and were detected not only in CD4+ cells but also in CD8+ cells. An increase in the proportion of AC1+ cells was also seen in activated T-cells. In contrast, AB1-positive cells were only detected in activated thymocytes, not in resting thymocytes, or resting or activated T-cells. These results implicate GD1c(NeuGc,NeuGc) in the activation of thymocytes as well as T-cells, whereas GD1b(NeuGc,NeuGc) appears to be specifically related to the activation of thymocytes.

[Reevaluation of heart disease deaths on death certificates and trends for ischemic heart disease mortality during the last five years in Oita city]

To evaluate heart disease deaths and clarify trends for ischemic heart disease (IHD) mortality during the last five years in Oita City, we reevaluated causes of death on death certificates. In 1993, there were 253,000 people aged 25-74 in Oita City. In this population age group, there were 1,996 deaths from January 1992 through December 1993. Our subjects were 982 deaths recorded as caused by heart disease and IHD related diseases. Subjects were reevaluated on the basis of physician's interview, clinical records and police records. This IHD reevaluation was conducted by the WHO MONICA criteria. The death certificates identified 321 heart disease deaths, of which there were 80 (24.9%) acute myocardial infarctions (AMI), 22 (6.9%) other IHD, 180 (56.1%) heart failures, and 39 (12.1%) other heart diseases. The remaining 61 deaths were caused by other diseases. After reevaluation, 40 'definite' AMI and 60 'possible' AMI were recognized through the MONICA criteria, 86 sudden deaths (SD) which were defined as, 'death within 24 hours of the onset of acute symptoms and without clear signs suggesting what disease was the cause,' were also classified. Assuming that 50% of SD were due to IHD, according to some postmortem autopsy studies, aged-standardized IHD mortality per 100,000 for males was 38.3 per year and for females 17.3 per year in this period. Both mortality rates, 31% for males and 38% for females, were higher than IHD mortality statistics. Moreover, in comparison with IHD mortality estimated by reevaluation of heart disease in Oita City in 1987-88, age-standardized IHD mortality per 100,000 for males has remained basically stable, increasing from 37.8 to 38.4 during the last five years. On the other hand, mortality for females has increased from 11.2 to 17.3. Our results suggest that mortality from IHD actually was about 30% more than mortality statistics, and does not show a declining trend as mortality statistics have stated.

Heart disease deaths on death certificates re-evaluated by clinical records in a Japanese city

In order to estimate the number of deaths from ischemic heart disease (IHD) in a Japanese city, we reevaluated heart disease deaths among residents aged 25-74 years by examining their clinical records. During the 2-year period from 1987 to 1988, 271 deaths among this population were attributed to heart disease. The recorded underlying cause of death was IHD in 96 cases, heart failure in 123 cases, and other heart disease in 52 cases. Re-evaluation of the cause of death yielded 57 cases of acute myocardial infarction (AMI), 85 cases of sudden death, 37 cases of heart disease other than IHD, and 63 cases of non-heart disease. In the remaining cases, there was insufficient information for evaluation. According to some autopsy studies, about 50% of sudden deaths are due to IHD. Thus, 50% of the number of sudden death cases may be added to the total number of IHD deaths. Accordingly, the total number of IHD deaths may have been 100, ie, 57 cases of AMI plus 43 cases of sudden death. The difference between the number of IHD deaths after re-evaluation and the number for which IHD was recorded as the underlying cause was small, with the former only 4% higher than the latter. The number of false-positives was equal to the number of false-negatives, and hence the number of IHD deaths recorded in this area seems to be close to the actual figure. We speculate that more accurate death certification will result in a decrease in the total number of deaths attributable to heart disease, as in 23% of deaths attributed to heart disease the underlying cause of death was not in fact heart disease.

Specific reduction of plasma large, light low-density lipoprotein by a bile acid sequestering resin, cholebine (MCI-196) in type II hyperlipoproteinemia

The effect of a bile acid sequestrant, cholebine (3 g/day), on plasma lipoprotein subfractions was investigated in 16 patients with type II hyperlipoproteinemia. Activities of low density lipoprotein (LDL)-receptor and activities of lecithin:cholesterol acyltransferase (LCAT) and cholesteryl ester transfer protein (CETP) were assayed to address the mechanism of cholebine-induced changes in plasma lipoprotein subfractions. Twelve weeks of treatment with cholebine reduced plasma levels of total cholesterol (TC) and LDL-cholesterol (C) by 8.3 +/- 8.1% (mean +/- S.D.) and 14.4 +/- 11.9%, respectively (P < 0.001), but did not affect plasma levels of high density lipoprotein (HDL)-C. Cholebine significantly reduced plasma levels of LDL1-C (1.019 < d < 1.045) by 22.9 +/- 18.9% (P < 0.001) but did not affect plasma levels of very low density lipoprotein (VLDL)-C, intermediate density lipoprotein (IDL)-C, LDL2-C (1.045 < d < 1.063), HDL2-C, and HDL3-C (d > 1.125). Gradient polyacrylamide gel electrophoresis (PAGE) revealed that cholebine reduced large LDL in plasma but had almost no effects on small LDL and HDL subfractions. Cholebine did not alter the activities of LCAT and CETP. LDL-receptor activities of cultured lymphocytes negatively correlated with the reduction in plasma levels of LDL-C (r = -0.500, P < 0.05), IDL-C (r = -0.581, P < 0.02), and LDL1-C (r = -0.610, P < 0.01), respectively. Thus, cholebine seems to reduce further the plasma levels of IDL and large, light LDL in patients with lower LDL-receptor activities. We conclude that cholebine only reduces plasma levels of large, light LDL. This may be due to the stimulation of hepatic LDL-receptor activity.

Single-photon emission CT and MR findings in Klüver-Bucy syndrome after Reye syndrome

We present the MR and single-photon emission CT findings in a 3-year-old patient in whom Klüver-Bucy syndrome developed after Reye syndrome. MR images showed diffuse brain atrophy, which was predominant in the temporal lobes, and single-photon emission CT scans showed decreased cerebral perfusion in the bilateral temporal lobes and associated cortical areas.

Immunolocalization of tissue non-specific alkaline phosphatase in mice

Immunolocalization of tissue non-specific alkaline phosphatase (TNAP) was examined in murine tissues, employing a specific antiserum to TNAP on frozen sections, 50-micron tissue slices, and paraffin sections. TNAP was detected at high levels in hard tissues including bone, cartilage, and tooth. In bone tissue, the TNAP immunoreactivity was localized on the entire cell surface of preosteoblasts, as well as the basolateral cell membrane of osteoblasts. It was also localized on some resting chondrocytes and most of the proliferative and hypertrophic cells in cartilage. In the incisor, cells of the stratum intermedium, the subodontoblastic layer, the proximal portion of secretory ameloblasts, and the basolateral portion of odontoblasts showed particularly strong immunoreactivity. Immunoreactivity was observed in other soft tissues, such as the brush borders of proximal renal tubules in kidney, on cell membrane of the biliary canalicula in liver and in trophoblasts in the placenta. These immunolocalizations were quite similar to enzyme histochemical localizations. However, neither the submandibular gland nor the intestine, which both exhibited alkaline phosphatase activity by enzyme histochemistry, revealed immunoreactivity for TNAP. Therefore, immunocytohistochemical studies for TNAP enabled us to localize the TNAP isozyme, thus distinguishing it from other isozymes.

Cu, Zn-superoxide dismutase reaction in neonatal pontosubicular neuron necrosis

The immunohistochemical localization and changes in copper/zinc superoxide dismutase (Cu, Zn-SOD) were examined in 14 neonates with pontosubicular neuron necrosis (PSN), as compared with those in 15 controls in which the cytoplasm of neurons and glial cells showed SOD immunoreactivity. In the temporal lobes and hippocampus with PSN, Cu, Zn-SOD reactivity was negative in neurons at 0 and 1 days after birth, but was positive after 5 days of age in 8 of 10 cases. In the pons and cerebellum, SOD-positive neurons appeared soon after birth, but eosinophilic or karyorrhectic neurons were SOD negative. On the other hand, glial cells were positive after birth in all cases of PSN, and their reactivity was increased in the cases of reactive astrogliosis. Early loss of the scavenging system directed at free radicals may lead to neuronal damage, and the induction of Cu, Zn-SOD may act as a defense mechanism against damage of neurons in neonates with PSN. Therefore, oxygen-derived free radicals may be one of the pathogenetic factors of PSN with characteristics of apoptosis in neonates.

Expression of thyrotropin-releasing hormone (TRH) receptor mRNA in somatotrophs in the rat anterior pituitary

A response of growth hormone (GH) to thyrotropin-releasing hormone (TRH) is observed in lower mammals and patients with diseases such as a cromegaly, but not in normal subjects. We have previously demonstrated the existence of intact TRH receptor mRNA in GH-secreting adenoma. To examine whether intact somatotrophs in the anterior pituitary also express TRH receptor, we attempted to localize both TRHR mRNA and GH immunoreactivity simultaneously. In situ hybridization analysis revealed TRHR mRNAs specifically in the anterior pituitary, and 61.1% of the anterior pituitary cells expressed this transcript. Staining for GH and PRL on the same samples showed that the somatotrophs apparently expressed TRHR mRNA and approximately 62.3% and 30.9% of hybridization-positive cells were somatotorophs and mammotrophs, respectively. Moreover, TRHR mRNA level in the somatotrophs expressed as the number of silver grains per cell was equivalent to that in the mammotrophs. These findings demonstrated expression of the TRHR mRNA in somatotrophs in the rat anterior pituitary, and also showed that more than 50% of the TRHR mRNA detected in the anterior pituitary was derived from these cells.

Cell-specific expression of the parathyroid hormone (PTH)/PTH-related peptide receptor gene in kidney from kidney-specific and ubiquitous promoters

The kidney is the major site of expression of the PTH/PTH-related peptide receptor (PTHR) gene. Previously we have shown that the PTHR gene is expressed from two promoters in kidney, an upstream kidney-specific promoter (P1) and a downstream promoter (P2) that is active in a wide variety of tissues. Here, we have used immunohistochemical and transcript-specific in situ hybridization techniques to map the expression of the PTHR gene and protein and to determine the distribution of P1- and P2-driven messenger RNAs in renal tissue. Immunohistochemical and immunoelectron microscopic analysis showed that PTHR protein is expressed on both basolateral and luminal membranes of proximal tubular epithelial cells, strongly suggesting a bipolar mode of action of PTH. Receptor protein also was detected on the surface of glomerular podocytes. Strikingly, immunoelectron microscopic analysis showed that endothelial cells of the peritubular vasculature, but not the glomerular vasculature, contain high levels of PTHR protein. We found that both P1 and P2 are expressed at moderate levels in both cortical and medullary epithelial cells of nephrons, correlating well with the immunohistochemical localization of PTHR protein. However, although abundant transcripts were detected in peritubular endothelial cells with P1-specific and coding sequence probes, P2-specific expression was not observed in these cells. These results provide evidence that the physiological effects of PTH- and/or PTH-related peptide on renal tubular function may be mediated not only through direct effects on epithelial cells but also indirectly through endothelial cell-based signaling. In addition to expression in vascular endothelial cells, high levels of P1-specific, but not P2-specific, PTHR messenger RNA were detected in vascular smooth muscle. Taken together, these experiments provide evidence for strong PTHR gene expression in renal vascular tissues. Moreover, given that previous studies have shown that P2, but not P1, is active in other tissues with an abundant vasculature, our results suggest that regulation of PTHR gene expression in renal vascular tissue is distinct from that of other organs.

Alteration of glutamyltranspeptidase binding proteins in postmortem brains of heroin addicts

Glutamyltranspeptidase binding (G) proteins play an important role in intracellular signal transduction downstream from many receptors, including opioid receptors. Moreover, it was recently reported that the beta-subunits of G proteins, in addition to the alpha-subunits, regulate effector pathways. In this study, membrane G protein immunoreactivity was estimated by Western blotting with polyclonal antibodies (RM/1, AS/7, GC/2, QL, and SW/1) against specific G proteins (G alpha S, G alpha i-1,2, G alpha o, G alpha q, and G beta, respectively) in postmortem temporal cortex obtained from 6 heroin addicts and 6 control subjects without a history of drug abuse. Immunoreactivities of the G beta-subunit increased significantly (p < 0.05) in heroin addicts, compared with controls, and that of G alpha i-1,2 tended to increase in heroin addicts. Present findings suggest that the alterations in G protein-mediated signal transduction may be involved in the mechanism of opiate addiction.

A case of moderate hypertriglyceridemia with apolipoprotein E phenotype E4/3

Hyperlipoproteinemic subjects with apo(lipoprotein)E4 are usually hypercholesterolemic and those with apoE2 are hypertriglyceridemic. We report a case of moderate hypertriglyceridemia with apoE phenotype E4/3. Plasma levels of total cholesterol (TC), triglyceride (TG), high density lipoprotein (HDL)-C, apoAI, apoB, apoCII, apoCIII, and apoE were 200mg/dL, 451 mg/dL, 31 mg/dL, 115 mg/dL, 99 mg/dL, 10.0 mg/dL, 22.2 mg/dL, and 12.0 mg/dL, respectively. Plasma levels of very low density lipoprotein (VLDL)-C and intermediate density lipoprotein (IDL)-C were high, and those of low density lipoprotein (LDL)-C and HDL2-C were low. All lipoprotein subfractions except VLDL were TG-rich. These findings are common in moderate hypertriglyceridemia. The plasma level of remnant-like particle (RLP, equivalent to chylomicron remnant)-C, was high. The lipoprotein lipase which removes TG from chylomicron and VLDL was normal. The activity of LDL receptor which removes remnants of chylomicron and VLDL as well as LDL was high. ApoE4 actively binds to receptors of remnant and LDL. Thus, the removal of TG-rich lipoproteins should not be impaired in this patient. Plasma levels of insulin during oral glucose tolerance test were high. Hyperinsulinism stimulates VLDL synthesis in the liver. Subjects with apoE4 show active synthesis of chyromicron. Thus, we concluded that the moderate hypertriglyceridemia in this E4/3 patient was due to the overproduction of chylomicron and VLDL.

Reduced immunoreactivity of adenylyl cyclase in dementia of the Alzheimer type

The amounts of three adenylyl cyclase (AC) subtypes in membranes from brain obtained post-mortem from patients with dementia of Alzheimer type (DAT) and controls were studied by Western blotting using polyclonal antibodies. AC subtypes were characterized by preabsorption by complementary peptides, species difference, tissue distribution and by using AC-VI-transfected cells. Immunoreactivities of AC-I and AC-II subtypes, which are predominant in brain tissue were decreased 40.5% (p < 0.02) and 52.0% (p < 0.02), respectively in DAT compared with controls. No significant difference in immunoreactivity of AC-V/VI subtypes distributed in various other tissues was observed. Our results are the first to indicate that reduced levels of brain-specific AC subtypes occur in DAT.