A Three-dimensional Analysis of Blood Vessels in Bronchioloalveolar Carcinoma

The three-dimensional architecture of blood vessels within lung adenocarcinomas has not been well studied. In 19 cases with bronchioloalveolar carcinoma with central fibrosis, we three-dimensionally examined blood vessel architecture in 150 m thick sections stained with elastin staining and anti-CD34 antibody. We examined four regions: normal alveoli and three regions within the tumor including an area adjacent to the normal alveoli (external area), an area in which tumor cells were replacing epithelial cells (replacement area), and a central fibrotic area (fibrotic area). Elastin staining showed that elastic fibers formed the framework of the alveoli, and the alveolar structure shrank more strongly to the center of the tumor due to folding of alveolar walls invaded by adenocarcinoma cells. We also measured three vessel parameters in these four regions. The vessel diameters were 4.08±1.10 m, 3.95±1.02 m, 5.04±1.56 m, and 6.11±2.23 m, the circumferences of those vessels seen as complete circles were 43.11±12.78 m, 43.71±12.87 m, 95.21±39.32 m, and 126.77±54.65 m; the lengths between vessel bifurcations were 13.28±3.08 m, 13.47±4.58 m, 24.91±9.66 m, and 41.82±28.08 m in the normal alveoli, and the external, replacement, and fibrotic areas, respectively. Blood vessel architecture changed such that the vessels became larger and coarser towards the center of the tumor. Our three-dimensional analysis suggests continuous remodeling of alveolar capillaries rather than angiogenesis within bronchioloalveolar carcinoma.     

Depressed selenium and vitamin E levels in an alcoholic population

Serum selenium and vitamin E levels have been measured in subjects with established alcoholic liver disease, in alcoholics within the community, and in appropriate controls. Both serum selenium and vitamin E levels were shown to be significantly depressed (P<0.01) in the alcoholic study groups and serum selenium was more markedly depressed in subjects with established liver disease (controls, serum selenium 108±13 g/liter, vitamin E 27.6±7.2 mol/liter; community alcoholics, serum selenium 94±19 g/liter, vitamin E 15.3±3.4 mol/liter; alcoholic liver disease, serum selenium 78±15 g/liter, vitamin E 14.7±5.6 mol/liter). Depressed serum selenium levels correlated closely with poor nutritional status (r=0.91). There were no changes in serum glutathione peroxidase activity. Liver disease activity, as judged by transaminase (AST), was more markedly abnormal in subjects with combined vitamin E and selenium deficiency compared to those with normal levels or isolated deficiencies (no deficiency, AST 48±19 units, combined deficiency, AST 75±21 units,P<0.03). Serum lipid peroxides were elevated in those with combined deficiency and the values correlated significantly with serum transaminases (r=0.40,P=0.03).     

Synovial fluid nitric oxide levels in patients with knee osteoarthritis

Nitric oxide (NO) has an important role in the inflammatory arthropathies. This study investigated NO levels in the synovial fluid and plasma of patients with primary osteoarthritis (OA) of the knee. Twenty-seven cases with primary knee OA and 13 controls were recruited for the study. Nitrate/nitrite levels of synovial fluid and plasma were measured by Griess reaction, and interleukin-1 (IL-1) levels were measured quantitatively by a sandwich immunoassay technique. We found a significant increase in the synovial fluid nitrate/nitrite levels in cases with primary OA of the knee compared to controls (50.26±23.63 g/l vs 32.49±10.05 g/l, p=0.002) as well as increased plasma nitrate/nitrite levels (57.06±23.32 g/l vs 39.98±16.36 g/l, p=0.012). There was no difference in plasma and synovial fluid IL-1 concentrations between the study and control groups. These results may be considered as supporting evidence that NO might be one of the factors responsible for cartilage destruction in primary osteoarthritis of the knee.Abbreviations NO Nitric oxide - OA Osteoarthritis - TMJ Temporomandibular joint     

Increased uptake of low density lipoprotein by SV40-transformed smooth muscle cells

We compared the metabolism of low density lipoprotein (LDL) in SV40-transformed smooth muscle cells (TSMCs) to that in nontransformed smooth muscle cells (SMCs). When SMCs were incubated in medium with 100 g/ml LDL for 24 hours, they did not accumulate sudanophilic lipid droplets. On the other hand, when TSMCs were incubated in medium containing more than 100 g/ml LDL, they accumulated a large amount of lipid droplets in their cytoplasm. When cells were incubated with 200 g/ml LDL for 24 hours, cholesteryl ester levels significantly increased in TSMCs (18.3±3.53 g/mg protein), as compared with SMCs (2.40±0.85 g/mg protein). However, there was no difference in the cellular level of free cholesterol between the TSMCs and SMCs. Although the TSMCs and SMCs had a similar number of binding sites for LDL, the TSMCs demonstrated a markedly higher uptake of LDL labeled with 1,1-dioctadecyl-3,3,3,3-tetramethyl indocarbocyanine perchlorate (Dil-LDL), compared with the SMCs. SMCs that had been pretreated with 100 g/ml of unlabeled LDL for 24 hours showed a decreased uptake of Dil-LDL. In contrast, TSMCs incorporated Dil-LDL independently of the preincubation with 100 g/ml LDL. The presence of brefeldin A, which may block the transport of glycoproteins from the ER to Golgi apparatus, had less of an effect on the uptake of LDL in the TSMCs than in the SMCs. These results suggest that SV40-transformed smooth muscle cells show an increased uptake of LDL independent of the cellular cholesterol level, which may induce the accumulation of lipid droplets in their cytoplasm. A LDL receptor-independent pathway may be related to the increased uptake of LDL in SV40-transformed smooth muscle cells.     

The circulating molecular weight forms of infused recombinant insulin-like growth factor-I and effects on glucose and fat metabolism in lambs

Summary We have investigated the relationship between the plasma distribution of infused recominant insulin-like growth factor-I across the insulin-like growth factor binding proteins and the resultant effects on glucose and fat metabolism. The studies were performed in 24-h fasted ram lambs which received primed constant infusions of ³H labelled glucose tracer. When isotopic equilibrium had been reached, the animals received 90-min infusions of human insulin-like growth factor-I at various doses (2.5, 20, 40 and 120 g· kg^–1·h^–1, n=3 for each dose). Total plasma insulin-like growth factor-I was significantly elevated by infusion at a rate of 40 g·kg^–1·h^–1 (from 185±14 g/l to 442±41 g/l, p<0.05) and 120g·kg^–1h^–1 (from 181±2 g/l to 953±39 g/1, p<0.005). The plasma concentrations of insulin-like growth factor-I not associated with binding proteins remained undetectable (<15 g/l) at the end of the 2.5 and 20 g·kg^–1·h^–1 doses, but were significantly elevated at the end of the 40 and 120 g·kg^–1·h^–1 infusions (to 71±14 g/l, p<0.05 and 176±55 g/l, p<0.01 respectively). The infused insulin-like growth factor-I associated primarily with 35–60 kilodalton binding proteins. Glucose kinetics were significantly altered only by the highest dose infusion, during which there was a fall in plasma glucose concentration from 3.5±0.2 mmol/l to 1.9±0.2 mmol/l (p<0.05). This was due to a 51% increase in the rate of glucose clearance. There was no significant change in the rate of glucose production. The plasma concentrations of glycerol and non-esterified fatty acid were not changed by any of the doses infused. We conclude that the hypoglycaemic action of infused recombinant insulin-like growth factor-I relates to a marked elevation of free insulin-like growth factor-I in the plasma, but that a threshold concentration of free insulin-like growth factor-I must be exceeded before this action is observed. The hypoglycaemic action of recominant insulin-like growth factor-I results primarily from an increase in glucose clearance while glucose metabolism was more sensitive than fat metabolism to infused recominant insulin-like growth factor-I. Both these actions contrast with those of insulin, and suggest that the acute metabolic effects of recombinant insulin-like growth factor-I are not mediated simply by cross-reaction with insulin receptors.     

Site of Bismuth Absorption from Bismuth Subsalicylate

Poorly absorbed bismuth preparations may benefit a variety of chronic colonic conditions including ulcerative colitis. Bismuth-induced neurotoxicity is a potential complication of the chronic use of these preparations, and a less-absorbable form of bismuth is needed. If bismuth absorption occurs primarily in the upper gut, a delayed-release bismuth preparation could reduce absorption. We studied the site of bismuth absorption from bismuth subsalicylate (BSS) in rats. For 15 days, BSS (50 mg/day) was ingested or infused directly into the cecum via a chronically implanted cannula. Oral BSS resulted in serum and urine bismuth levels many times higher (3.5 ± 0.3 g/liter and 1570 ± 286 g/g creatinine, respectively) than with cecal administration (undetectable (<1.5 g/liter) and 75 ± 25 g/g creatinine). Thus, bismuth absorption from BSS occurred almost entirely in the upper gut. These findings provide a rationale for a similar study of delayed-release bismuth preparations in humans.     

Islet B-cell dysfunction and the time course of recovery following chronic overinsulinisation of normal rats

Summary Appropriate insulin therapy may preserve or improve islet B-cell function whereas the effects of overinsulinisation are unclear. Pancreatic islet B-cell function was therefore studied after overinsulinisation of normal rats for 4 weeks (fed blood glucose 2.2–4.5 mmol/l, controls 4.1–7.0 mmol/l). Insulin secretion was assessed by a 3-h hyperglycaemic clamp (10.0 mmol/l) performed 1, 48, and 120 h after insulin withdrawal (n=6 in each group). When the clamp was performed 1 h after insulin withdrawal, clamp insulin concentration was 1.6±0.1 g/l, compared to 9.3±1.0 g/l in control rats. The integrated area under the plasma insulin concentration curve was also significantly decreased (4.8±0.4 vs 20.3±2.2 g·l^–1·h^–1, p<0.001), but recovered to 9.4±1.0 g·l^–1·h^–1 after 48 h, and to 17.5±1.4 g·l^–1·h^–1 after 120 h. Pancreatic insulin contents were decreased at 1 h (6±1 g/g wet wt) and 48 h (54±12 g/g wet wt) but not at 120 h (221±30 g/g wet wt) after withdrawal (controls, 303±29 /g wet wt) and there was a strong relationship with pancreatic preproinsulin mRNA and the clamp insulin response. Thus, overinsulinisation with prolonged periods of low blood glucose concentrations impairs islet B-cell function, but is reversible over 5 days.     

In vivo assessment of the inotropic and toxic effects of oxidized ouabain

Summary Oxidized ouabain, a product of the oxidative cleavage of the rhamnose ring in ouabain has been found to have a higher inotropic toxic ratio in cultured cardiac myocytes.The purpose of our study was to evaluate the efficacy and toxicity of oxidized ouabain in comparison with ouabain in intact animals. Drugs were infused to healthy cats; the positive inotropic effect, and the time-course of development of arrhythmia were followed and recorded until death. Oxidized ouabain was associated with a higher increase in arterial blood pressure, a mean increase of 41±19% as compared with 21±8% in the ouabain group (p<0.10). There were no significant differences in maximal increases of dP/dt or dP/dt/P (65±29%, 28±10% for oxidized ouabain and 49±16%, 27±11% for ouabain, respectively). The mean doses causing persistent arrhythmia (toxic dose) were 93±23 g/kg of oxidized ouabain vs 39±14 g/kg of ouabain. Lethal arrhythmias were produced by 215±46 g/kg of oxidized ouabain and 62±16 g/kg of ouabain. The radio of toxic to lethal doses was 0.62±0.11 for ouabain vs 0.45±0.09 for oxidized ouabain (p<0.05), but the inotropic to toxic dose ratios were not different.We conclude that oxidized ouabain acts similarly to the known cardiac glycosides in doses which produce inotropic effects in cats, has a lower potency as compared to ouabain, and appears to have a more benign course of intoxication.     

Role of Central Interleukin-1β in Gastrointestinal Motor Disturbances Induced by Lipopolysaccharide in Sheep

Cytokines are involved in the symptoms of theacute phase response induced by infectious diseases inhumans as well as in animals, and interleukin-1(IL-1 ) has a pivotal role in these changes. The role of central IL-1 in the gastrointestinalhypomotility and fever evoked by intravenousadministration of lipopolysaccharide (LPS) and themechanisms involved, were investigated in sheep as anexperimental model. LPS (0.1 g/kg, intravenously)induced gastrointestinal hypomotility and fever thatwere significantly reduced by priorintracerebroventricular administration of IL-1receptor antagonist protein (IL-1ra, 2 g/kg). The effects of LPS were mimickedby intracerebroventricular IL-1 (50 ng/kg),whereas IL-1 injected intravenously at the samedose only caused a slight and transient fever withoutmodifying the gastrointestinal motility. Priorintracerebroventricular administration of thecyclooxygenase inhibitor indomethacin (100 g/kg) butnot the corticotropin-releasing factor (CRF) receptorantagonist -helical CRF_9-41 (5 g/kg) blocked alleffects evoked by both LPS and IL-1. These resultssuggest that in sheep, LPS induces digestive motordisturbances through a central release of IL-1 andprostaglandins.     

B cell adrenoceptors and sulphonylurea-induced insulin release in mouse islets

Summary Interactions of tolbutamide and glibenclamide with B cell adrenoceptors have been reported. This study evaluated the possible role of such interactions in the stimulation of insulin release. Mouse islets were incubated in the presence of 10 mmol/l glucose alone or with tolbutamide (10 mol/l) or glibenclamide (0.02 mol/l). At 0.01–10 mol/l, blockers of ₂-adrenoceptors (yohimbine, idazoxan) or ₁-adrenoceptors (prazosin) had practically no effect on glucose-induced insulin release and did not affect its potentiation by sulphonylureas, except for a slight increase by 10 mol/l prazosin and idazoxan. Nonspecific -blockers (phentolamine, dihydroergotamine) increased control release at 10 mol/l, but only the latter amplified the response to tolbutamide. Blockers of -adrenoceptors were tested at 0.1–100 mol/l: propranolol (₁, ₂), metoprolol (₁) and compound ICI 118-551 (₂). They increased glucose-induced insulin release at 100 mol/l but variably altered the effect of sulphonylureas. Blockers of adrenoceptors have, thus, no effect on insulin release in vitro at therapeutic concentrations. At high concentrations, they non-specifically affect the action of sulphonylureas. We conclude that an interaction with B cell adrenoceptors is not involved in the insulinotropic action of sulphonylureas.     

Gastric diversion or pylorus ligation for gastric mucosal integrity and acid secretion studies in the rat?

The advantages of gastric diversion over pylorus ligation in rat gastric mucosal integrity and acid secretion studies over 6 hr were investigated. Mucosal injury developed in 80% of pylorus-ligation controls. Atropine (5 mg/kg) or cimetidine (40 mg/kg) had no effect on this injury (2.9 mm²±0.9 and 2.8 mm²±0.7, respectively, vs 3.1 mm²±1, mean±sem, N=10; however vagotomy increased it (13.7 mm²±Pylorus-ligation H⁺ output was higher than that of gastric diversion (390.5 mol±54.8 vs 61 mol±2.5, mean±sem, N=10, P<0.001). Cimetidine (40 mg/kg) depressed H⁺ output of gastric diversion (21.3 mol±1.2 vs 61 mol±2.5, mean±sem, N=10, P<0.001), but not of pylorus ligation (424 mol±74.2 vs 390.5 mol±54.8, mean±sem, N=10). Vagotomy or atropine depressed pylorus-ligation H⁺ output (P<0.001), but each allowed an output (36.6 mol±5.5 and 120 mol±29, respectively, mean±sem, N=10) significantly (P<0.001) higher than that associated with it in gastric diversion (16 mol±1.4 and 17.1 mol±1.6, respectively, mean±sem, N=10). This study demonstrates that in the rat pylorus ligation, in contrast to gastric diversion, injures the gastric mucosa, stimulates H⁺ secretion, and overshadows the efficacy of antisecretory agents.     

Age-related Variations in the Neuroendocrine Control,More Than Impaired Receptor Sensitivity,Cause The Reduction in the GH-releasing Activity of GHRPs in Human Aging

The mechanisms underlying the reduction in the GH-releasing activity of GHRPs in aging are still unclear. Aim of our study was to verify in man whether age-related impairment of the neurohormonal control of GH secretion and/or receptor alterations are involved in the reduced GH response to GHRPs in aging. To this goal, in 16 normal elderly subjects (E, 66–81 yr) and 12 young controls (Y, 24–28 yr) we studied the effects of 1.0, 2.0 and 3.0 g/kg iv Hexarelin (HEX), a synthetic hexapeptide, or GHRH, as well as the interaction among HEX (2.0 g/kg), GHRH (2.0 g/kg) and arginine (ARG, 0.5 gr/kg) on GH secretion. In Y the GH response to increasing doses of HEX (1.0 vs. 2.0 vs. 3.0 g/kg; AUC0;v–120 ± SEM: 1728.4 ± 406.4 vs. 2265.9 ± 298.4 vs. 2934.3 ± 482.2 g//L/h, p < 0.05 for 1.0 vs. 2.0 g/kg) and GHRH (649.6 ± 111.4 vs. 792.2 ± 117.6 vs. 1402.6 ± 363.0 g/L/h) showed a progressive increase. Two g/kg HEX and 1 g/kg GHRH were the maximal effective doses. Similarly, in E the GH response to increasing doses of HEX (336.7 ± 50.0 vs. 742.8 ± 157.9 vs. 1205.1 ± 178.1 g/L/h, p < 0.05 for 1.0 vs. 2 g/kg, p < 0.001 for 1.0 vs. 3.0 g/kg and p < 0.03 for 2.0 vs. 3.0 g/kg) and GHRH (183.8 ± 27.3 vs. 260.9 ± 17.3 vs. 356.1 ± 46.3 g/L/h, p < 0.005 for 1.0 vs. 3.0 g/kg and p < 0.05 for 2.0 vs. 3.0 g/kg) showed a progressive increase. In E the GH response to 3 g/kg HEX or GHRH were clearly higher than those to 2 g/kg. However, at each dose the GH responses to HEX or GHRH in E were lower (p < 0.05) than those in Y. In Y the GH response to HEX + GHRH was synergistical (4259.2 ± 308.0 g/L/h, p < 0.05). ARG strikingly potentiated the GHRH-induced GH rise (2640.8 ± 273.6 g/L/h, p < 0.01) but not the HEX-induced one (2371.7 ± 387.2 g/L/h) as well as the synergistical effect of HEX and GHRH (4009.1 ± 360.8 g/L/h). In E the GH response to HEX and GHRH was still synergistical (1947.7 ± 306.0 g/L/h, p < 0.05) but these responses were lower than those in young (p < 0.01). On the other hand, in E ARG restored the GH response to GHRH (1858.9 ± 172.8 g/L/h, p < 0.01) and even those to HEX (2069.5 ± 528.7 g/L/h, p < 0.01) and HEX + GHRH (4406.0 ± 1079.2 g/L/h, p < 0.05). Our present results indicate that the impairment of GHRP and GHRH receptor activity may have a role in the reduction of the somatotrope responsiveness in aging. However, the age-related reduction in the GH-releasing activity of GHRPs seems mainly dependent on age-related variations in the neural control, i.e. concomitant GHRH hypoactivity and somatostatinergic hyperactivity.     

Cellular ionic effects of insulin in normal human erythrocytes: a nuclear magnetic resonance study

Summary Elevated erythrocyte cytosolic free calcium, and suppressed free magnesium and pH values are associated with the hyperinsulinaemia and insulin resistance of hypertension, obesity, and Type 2 (non-insulin-dependent) diabetes mellitus. To determine the role of insulin in this process, we utilized ¹⁹F- and ³¹P-nuclear magnetic resonance spectroscopy to study the cellular ionic effects of insulin in vitro on normal human erythrocytes. Insulin elevated cytosolic free calcium levels in a dose- and time-dependent manner. The effect began at 10 U/ml, peaked at 200 U/ml, and continued at both the 500 U/ml and 1000 U/ml doses. At 200 U/ml, free calcium levels rose from 24.6±2.5 nmol/l to a peak value at 120 min of 66.4±11 nmol/l (p<0.05 vs basal), levels remaining elevated throughout the incubation (45.7±5.6 nmol/l at 60 min, and 47.9±9.1 nmol/l at 180 min, p<0.05 vs basal, respectively). Similarly, insulin also increased intracellular free magnesium at all time points (basal: 177± 11 mol/l; 60 min: 209±19 mol/l; 120 min: 206±22 mol/l; and 180 min: 202±12 mol/l; p<0.05 vs basal at all times). No insulin-induced changes in pH were observed. We conclude (i) that insulin in physiological concentrations may participate in regulating divalent cations in the mature human erythrocyte, (ii) that insulin per se cannot account for the previously described cellular ionic lesions of hypertension and diabetes, and (iii) that future clinical studies of cell ion metabolism should be conducted in the fasting state, be controlled for ambient circulating insulin levels, or both.     

Pancreatic Fluid Hypersecretion in Rats After Acute Pancreatitis

Pancreatic exocrine function was examined inrats during the early stage of acute pancreatitisinduced by four subcutaneous injections of 20 mug/kgbody weight of cerulein at hourly intervals. Basalpancreatic fluid secretion at 6 hr after the first of fourcerulein injections was significantly elevated (27.6± 3.7 vs 17.4 ± 2.1 l/30 min incontrol, P < 0.01) and further increased with time,reaching the peak level at 24 hr (105.1 ± 4.6 l/30 min).Intravenous infusion of loxiglumide (50 mg/kg bodywt/hr), atropine (100 g/kg body wt/hr), oranti-secretin serum did not modify the fluidhypersecretion observed at 24 hr after induction of acute pancreatitis.Loxiglumide, when given 30 min before the first ceruleininjection, markedly reduced fluid secretion, but couldnot inhibit the fluid hypersecretion when applied after the last cerulein injection. Leakage ofEvans blue dye into pancreatic juice was slightly butsignificantly increased in postpancreatitic ratscompared with that in the control rats (1.30 ±0.17 vs 0.75 ± 0.08 g/ml, P 0.01),whereas that in the pancreas was not different from thecontrol rats. In vivo labeling with5-bromo-2-deoxyuridine showed active proliferation ofacinar and ductular cells at 6 hr. In addition, the fluid was rich inchloride (137.1 ± 2.5 at 24 hr vs 92.4 ±3.3 meq/liter in control, P < 0.01) but poor inbicarbonate concentration (39.0 ± 2.0 at 24 hr vs46.5 ± 1.9 mmol/liter in control, P < 0.01), indicating acinar cell secretion.These results indicate that pancreatic fluid secretionduring the early stage of acute pancreatitis induced bysupramaximal doses of cerulein was markedly increased not by CCK-, secretin-, orcholinergic-dependent mechanisms but probably by acinarcell proliferation.     

Granulocyte elastase in assessment of severity of acute pancreatitis

Complexes of granulocyte elastase and ₁-antitrypsin are markers for granulocyte activation. In 75 patients with acute pancreatitis these complexes were immunologically determined daily in plasma during the first week of hospitalization. Patients were classified into three groups: mild pancreatitis (I, 1 complication, N=34), severe pancreatitis (II, 2 complications, N= 29), lethal outcome (III, N=12). Initially, granulocyte elastase (mean±sem) was lower in group I (348±39 g/liter) as compared to groups II (897±183 g/l) and III (799±244 g/liter), P<0.001 for I vs II + III. Initial elastase concentrations >400 g/liter were consistent with a severe or fatal course of the disease but did not distinguish between severe and lethal pancreatitis. In patients with mild or severe disease, mean elastase concentrations decreased continuously during the following days (197±15 g/liter in mild cases, 325±30 g/liter in severe cases at day 7). In patients with lethal disease, however, mean elastase concentrations even increased at day 2 and remained higher than 700 g/liter during the observation period. At days 1 and 2 the predictive value for severe or lethal disease of raised (>400 g/liter) elastase concentrations [positive predictive value (PPV) 82%, negative predictive value (NPV) 81%] was better than that of elevated (>100 mg/liter) C-reactive protein (PPV 73%, NPV 73%), elevated (>4.0 g/liter) ₁-antitrypsin (PPV 59%, NPV 50%), or decreased (<1.5 g/liter) ₂-macroglobulin (PPV 82%, NPV 67%). When the time course of the concentrations of the acute-phase proteins was studied, it was found that rises of granulocyte elastase were followed by elevated C-reactive protein levels after one day, by elevated ₁-antitrypsin levels after two days and by decreased ₂-macroglobulin levels after three to four days. We conclude that granulocyte elastase is a good early marker for the severity of acute pancreatitis. Compared with elevated levels of C-reactive protein and ₁-antitrypsin release of granulocyte elastase reflects an event that precedes acute-phase protein induction.     

Efficacy and Tolerability of the Long-Acting Somatostatin Analog Lanreotide in Acromegaly. A 12-Month Multicenter Study of 58 Acromegalic Patients

Objective: To determine the effects of the new somatostatin analogue, lanreotide, in its prolonged released form (PR), in patients with acromegaly.Design: Prospective open multicenter non comparative study.Setting: Thirty-three university-affiliated medical centers.Patients: One hundred sixteen acromegalic patients with active disease, of whom 58 patients complied with the protocol and completed the 12-month period treatment.Intervention: Lanreotide PR treatment was started at a dose of 30 mg intramuscularly every 14 days. If integrated mean plasma GH levels were not below 5 g/L and/or IGF-I levels were not normalized after one month of treatment, injections were given every 10 days. The duration of the study was 12 months.Results: After one month of treatment mean plasma GH and IGF-I levels had fallen from 10.7 ± 11.1 g/L (mean ± SD; range, 2.6 – 74.8 g/L; median, 7 g/L) and 718 ± 270 g/L (range 338 – 1440 g/L; median, 645 g/L), respectively, to 7.8 ± 10.1 g/L and 575 ± 252 g/L, respectively. Thirty patients (22%) had plasma GH levels below 2.5 g/L, and 8 patients (16%) had age-adjusted normal plasma IGF-I levels. At the sixth month of treatment mean plasma GH levels of 2.5 g/L or less, and normal plasma IGF-I levels were observed in 33%, and 33% of patients, respectively. At the twelvth month of treatment, these percentages were 41%, and 41%, respectively. The interval between two injections was shortened (one injection every 10 days) in 8 of the 58 patients (13%) at the second month of treatment, and at the end of the study, 70% of patients required 3 injections per month. The most frequent adverse event elicited by enquiry was transient diarrhea (76% of patients), followed by abdominal pain (62%) and pain at the injection site (59%). Based on the analysis of a subgroup of 46 patients who had at least a measurement of fecal fat content after day 0 of the study, a non significant increase (from 4.2 ± 3.4 to 5.1 ± 4.3 g/24h, p = 0.3) in mean steatorrhea was observed during treatment. Before treatment, steatorrhea was present in 9 (19%) patients. During the study, 15 additional patients (32%) developed persistent steatorrhea, and there was a transient increase in fecal fat content above 6 g/24 h in another 11 patients. After exclusion of the 7 patients (12%) with gallstones at enrolment, new gallstones were diagnosed in 6 out of 50 patients (12%) during the study.Conclusion: Two or three monthly injections of lanreotide PR decreased GH concentration to less than 2.5 g/L and normalized IGF-I levels in 41% of patients treated during 12 months. The good tolerability of this treatment, and the reduction in the frequency of injections, plus the sustained drug serum concentrations, confirm the usefulness of this new somatostatin analog formulation.     

Deleterious effects of digitalis on reperfusion-induced arrhythmias and myocardial injury in ischemic rat hearts: possible involvements of myocardial Na+ and Ca2+ imbalance

Summary Isolated rat hearts were made ischemic for 25 min after an initial recirculating perfusion, followed by 30 min of reperfusion. In some hearts, interventions including administration of ouabain and/or high [K⁺] in the buffer were performed during the first 10 min of reperfusion.During ischemia, intracellular Na⁺ (Na_i) increased from 15 to 64 [mol/g dry weight (dwt). During reperfusion, Na_i declined rapidly (at 10 min of reperfusion: 48 nol/g dwt, at 30 min: 25 mol/g dwt) and regular rhythm was recovered within 10 min in hearts without any intervention during reperfusion.⁴⁵Ca²⁺ uptake increased from 0.8 to 7.5 mol/g dwt after 30 min of reperfusion. Ventricular function recovered by 45 %.A 10-min perfusion with 10 or 50 M of ouabain increased Na_i (17 to 21 or 27 mol/g dwt) with increased left-ventricular (LV) contractile function, but these effects were reversed by combination of high perfusate [K⁺] (20 mM) in non-ischemic hearts.A 10-min reperfusion with ouabain retarded or stopped the decline in Na_i (at 10 min of reperfusion: 54 or 63 mol/g dwt, at 30 min: 32 or 40 mol/g dwt). These amounts of ouabain also increased the incidence of ventricular tachyarrhythmias during reperfusion to 30 % or 50 %, and increased the duration of ventricular fibrillation from 6.5 to 11.5 or 18.0 min.⁴⁵Ca²⁺ uptake reached to 8.8 or 10.0 mol/g dwt, and function recovered only 35 % or 28 %. When high perfusate [K⁺] was combined with ouabain during reperfusion, the retarded decline in Nai, augmented⁴⁵Ca²⁺ uptake, and reduced recovery of function caused by ouabain alone were attenuated. These results suggest that digitalis has toxic effects on reperfused ischemic hearts by inhibition of rapid active outward transport of previously elevated Na_i and potentiation of Ca²⁺ overload.The work was supported in part by grant HL 37936 from the National Heart, Lung and Blood Institute. J. R. Neely was deceased on November 29, 1988     

Developmental changes in the fatty (fafa) rat: Evidence for defective thermogenesis preceding the hyperlipogenesis and hyperinsulinaemia

Summary Preobese fatty rats have been identified by their lower rectal temperature. Of 51 pups born from matings of heterozygote (Fafa) parents, 16 had low rectal temperatures from day 16 onward (34.6±0.2° C v 35.4±0.3° C) and all subsequently became obese. No animal with the higher normal rectal temperature developed obesity. Hepatic fatty acid synthesis (preobese 0.6±0.1; lean 0.6±0.1 mol/ g/h), hepatic glucose-6-phosphate dehydrogenase activity (G6PDH) (preobese 0.68±0.07; lean 0.71 ±0.03 mol/g/min) and serum insulin (preobese 64 ±2; lean 58±4 U/ml) were unchanged in 18 day preobese, suckling fafa rats. 3 days after weaning hepatic lipogenesis (preobese 25.3±2.0; lean 5.4±0.7 mol/g/h) and G6PDH activity (preobese 4.5±0.5; lean 0.90±0.05 mol/g/min) had increased in both lean and preobese rats although the values attained in preobese rats were significantly greater than in lean rats. When weaning was delayed there was no enhancement in lipogenesis, G6PDH or serum insulin in the preobese rat. The results suggest that the primary genetic defect in fatty rats is not related to the increase in lipogenesis or serum insulin but may reflect a defective thermogenic process.     

Iron stores in 1359, 30- to 60-year-old Danish women: Evaluation by serum ferritin and hemoglobin

Summary Iron status, including serum (S-)ferritin and hemoglobin (Hb), was assessed in a population survey comprising 1359 nonpregnant Danish women in age cohorts of 30, 40, 50, and 60 years. S-ferritin levels were similar in 30- and 40-year-old women; they displayed a significant increase in 50-year-old women and a further significant increase in 60-year-old women. In the 30- and 40-year-old women, median S-ferritin was 38g/l, 5–95 percentile 6–135g/l; 17.2% had values < 15,g/l (i.e., depleted iron stores), 22.7% values from 15 to 30g/l (i.e., small iron stores), and 60.1% values > 30g/l (i.e., replete iron stores). In the 50-year-old women, median S-ferritin was 54g/l, 5–95 percentile 10–164g/l; 10.3% had values < 15g/l, 16.5% values from 15 to 30g/l, and 73.2% values > 30g/l. For the 60-year-old women, median S-ferritin was 84g/l, 5–95 percentile 25–249g/l; 1.6% had values < 15g/l, 8.6% values from 15 to 30g/l, and 89.8% values > 30g/l. Blood donors (n=180) had lower S-ferritin than nondonors in all age-groups (p<0.001). In the entire series, Hb levels were similar in 30- and 40-year-old women, median 137 g/l (8.5 mmol/l), 5–95 percentile 121–152 g/1 (7.5–9.4 mmol/l), and higher in 50- and 60-year-old women, median 140 g/l (8.7 mmol/l), 5–95 percentile 123-158 g/l (7.6–9.8 mmol/l) (p<0.0001). Hb values < 121 g/l (7.5 mmol/l) were observed in 3.8% of the women. Women with S-ferritin < 15 g/l (n=161) had lower Hb, median 134 g/l (8.3 mmol/l), than those with S-ferritin > 15 g/l, median 139 g/l (8.6 mmol/l) (p<0.001). Iron deficiency anemia (S-ferritin < 15 g/l and Hb < 121 g/l) was seen in 2.3% of 30- and 40-year-old women, and in 1.1% of 50- and 60-year-old women.     

The digoxin-amiodarone interaction

Summary To assess the cause of the digoxin-amiodarone interaction, the systemic availability and renal excretion of digoxin were examined in 10 patients. Patients were studied before and after 1 week and 6 weeks of concurrent amiodarone therapy, and four were also studied after 4–8 months.Mean (±SD) peak plasma digoxin concentration rose from 1.55±0.6 g/l prior to amiodarone therapy to 2.85±1.3 g/l after 1 week of combined therapy (p<0.01). Mean AUC also rose from 7.2±2.1 g/l.h to 12.1±6.4 g/l.h (p<0.01) during this period. Mean peak plasma digoxin concentration and AUC remained elevated after 6 weeks and, in the patients studied, at 4–8 months. Mean urinary digoxin clearance remained unchanged. Plasma amiodarone and desethylamiodarone concentrations were consistent with the prescribed doses.This study confirmed previous findings of raised plasma digoxin concentrations following the addition of amiodarone. It has also shown that this interaction is sustained for at least several months. The cause has not been fully elucidated but does not appear to be due to a change in the renal clearance of digoxin.