Phenotypic characteristics of pediatric inflammatory bowel disease in Japan: results from a multicenter registry

BACKGROUND/AIMS

There are few published registry studies from Asia on pediatric inflammatory bowel disease (IBD). Registry network data enable comparisons among ethnic groups. This study examined the characteristics of IBD in Japanese children and compared them with those in European children.

METHODS

This was a cross-sectional multicenter registry study of newly diagnosed Japanese pediatric IBD patients. The Paris classification was used to categorize IBD features, and results were compared with published EUROKIDS data.

RESULTS

A total of 265 pediatric IBD patients were initially registered, with 22 later excluded for having incomplete demographic data. For the analysis, 91 Crohn's disease (CD), 146 ulcerative colitis (UC), and 6 IBD-unclassified cases were eligible. For age at diagnosis, 20.9% of CD, 21.9% of UC, and 83.3% of IBD-unclassified cases were diagnosed before age 10 years. For CD location, 18.7%, 13.2%, 64.8%, 47.3%, and 20.9% were classified as involving L1 (ileocecum), L2 (colon), L3 (ileocolon), L4a (esophagus/stomach/duodenum), and L4b (jejunum/proximal ileum), respectively. For UC extent, 76% were classified as E4 (pancolitis). For CD behavior, B1 (non-stricturing/non-penetrating), B2 (stricturing), B3 (penetrating), and B2B3 were seen in 83.5%, 11.0%, 3.3%, and 2.2%, respectively. A comparison between Japanese and European children showed less L2 involvement (13.2% vs. 27.3%, P< 0.01) but more L4a (47.3% vs. 29.6%, P< 0.01) and L3 (64.8% vs. 52.7%, P< 0.05) involvement in Japanese CD children. Pediatric perianal CD was more prevalent in Japanese children (34.1% vs. 9.7%, P< 0.01).

CONCLUSIONS

Upper gastrointestinal and perianal CD lesions are more common in Japanese children than in European children.

The enhancement effect of three sugar alcohols on the fungicidal effect of benzethonium chloride toward Candida albicans

OBJECTIVE

The purpose of this study was to evaluate if the sugar alcohols erythritol, xylitol and sorbitol enhance the fungicidal effect of benzethonium chloride (BTC) toward in vitro candidal biofilms.

METHODS

An in vitroCandida albicans biofilm was formed on a plastic coverslip coated with type I collagen. The enhancement of the fungicidal effect was evaluated using microbial assay after treating the biofilm with the test solutions (sugar alcohols: erythritol, xylitol, and sorbitol, each containing BTC solution).

RESULTS

No fungicidal effect was observed with sugar alcohols without BTC. The fungicidal effect of erythritol-containing BTC increased with the erythritol concentration. Further, the level of enhancement of erythritol was the highest in three sugar alcohols.

CONCLUSION

Sugar alcohols, especially erythritol, enhanced the fungicidal effect of BTC toward in vitro candidal biofilms.

Reciprocal regulation of cultured human mast cell cytokine production by IL-4 and IFN-gamma

BACKGROUND

T(H)1 and T(H)2 cytokines are thought to regulate allergic inflammation.

OBJECTIVE

Two key regulatory cytokines, IL-4 and IFN-gamma, were examined for their effects on cytokine production by cultured human mast cells (CHMCs).

METHODS

CHMCs were obtained by culturing cord blood-derived CD34(+) cells in the presence of stem cell factor and IL-6 for 14 to 16 weeks. CHMCs were passively sensitized with human myeloma IgE and supplemented with or without IL-4 or IFN-gamma. After the sensitization, CHMCs were stimulated with anti-FcepsilonRIalpha mAb. Concentrations of secreted cytokines were measured by using ELISA, and cytokine messenger RNA was analyzed by using quantitative competitive RT-PCR.

RESULTS

IL-4 profoundly enhanced FcepsilonRI-mediated production of macrophage inflammatory protein (MIP) 1alpha, IL-8, and GM-CSF. For example, the enhancement by IL-4 (10 ng/mL) of the production of MIP-1alpha, IL-8, and GM-CSF was 25-, 7-, and 90-fold, respectively, after 6 hours. IL-4 also enhanced levels of FcepsilonRI-induced cytokine messenger RNA but to a lesser degree. In contrast, IFN-gamma inhibited FcepsilonRI-induced production of MIP-1alpha, IL-8, and GM-CSF. For example, the inhibition by IFN-gamma (10 ng/mL) of FcepsilonRI-mediated production of MIP-1alpha, IL-8, and GM-CSF was 80%, 75%, and 95%, respectively. IFN-gamma also suppressed FcepsilonRI-induced messenger RNA expression of these cytokines. Neither IL-4 nor IFN-gamma affected the kinetics of cytokine production by CHMCs.

CONCLUSION

These data suggest that IL-4 and IFN-gamma may influence allergic reactions by modulating human mast cell cytokine production.

Antihypertensive properties of KRN4884, a novel long-lasting potassium channel opener

The antihypertensive action of KRN4884 (5-amino-N-[2-(2-chlorophenyl)ethyl]-N'-cyano-3-pyridinecarboxamidine ), a newly synthesized 3-pyridine derivative was examined in conscious spontaneously hypertensive rats (SHRs). A single administration of KRN4884 (0.5, 1.5 mg/kg, p.o.) produced a dose-dependent and long-lasting antihypertensive effect. The 7-day repeated administration of KRN4884 (0.5, 1.5 mg/kg, p.o.) did not diminish antihypertensive activity during the treatment period or induce rebound hypertension after the discontinuation of treatment. To examine the mechanism of the antihypertensive effect of KRN4884, we studied its vasorelaxing effects in rat isolated aortae precontracted with 25 mM KCl. Single application of KRN4884 showed a slower onset of inhibitory action than that of levcromakalim. KRN4884 was approximately 26-fold more potent than levcromakalim and 10-fold less potent than nilvadipine. KRN4884- and levcromakalim-induced vasorelaxation were antagonized by glibenclamide. Furthermore, we observed the recovery of the contraction inhibited by these drugs after repeated washing. The inhibitory effect of KRN4884 was restored only after four washes, whereas that of levcromakalim was completely restored after one wash. The nilvadipine-induced inhibitory effect was the most resistant to washing among these drugs. These results suggest that KRN4884 shows a long-lasting antihypertensive effect based on its potent potassium channel-opening action. The long-lasting action may be due to a slow association/dissociation with/from the binding sites on vascular smooth muscle.

Cyanoamidines. II. Synthesis and pharmacological activity of N-arylalkyl-N'-cyano-3-pyridinecarboxamidines

A new series of cyanoamidines, N-arylalkyl-N'-cyano-3-pyridinecarboxamidines was synthesized and evaluated for inhibitory effects on 40 mM KCl-induced contraction and norepinephrine (NE)-induced contraction of rat aorta strips. The N-phenethyl cyanoamidine 4c showed potent vasodilatory action. Further in vitro screening program using 4c as a lead compound resulted in the discovery of highly potent N-[2-(2-chlorophenyl)ethyl]-N'-cyano-3-pyridinecarboxamidine (5j). Compound 5j induced the greatest increase in 86Rb+ efflux among cyanoamidine series. Subsequent modification of the pyridine ring of 5j was performed with evaluation for intravenous and oral antihypertensive activities. Introduction of an amino group at the 5-position of the pyridine ring furnished the new potassium channel opener, 5-amino-N-[2-(2-chlorophenyl)ethyl]-N'-cyano-3-pyridinecarboxamidine+ ++ (9e; KRN4884), which showed highly potent antihypertensive activity and a long duration of antihypertensive action after oral administration. KRN4884 is under further development as an antihypertensive agent.

Comparative vasodepressor effects of 3-pyridine derivatives possessing the cyanoamidine or amide structure in pithed rats

The potency and mechanism of the vasodepressor action of N-cyano-3-pyridinecarboximidamide and nicotinamide, which are 3-pyridine derivatives possessing cyanoamidine and amide structures, respectively, were studied in pithed rats infused with phenylephrine. The N-substituents of cyanoamidine and amide in the derivatives studied comprised 2-nitroxyethyl (KRN2391 and nicorandil), phenethyl (Ki769 and Ki765) and 2-(2-chlorophenyl)ethyl (Ki3005 and Ki4261) moieties. These derivatives produced vasodepressor actions in a dose-dependent manner, except for Ki4261 which did not show any action below the solubility limit. When the vasodepressor effects of compounds possessing the same N-substituents in cyanoamidine and amide derivatives were compared, the potency of cyanoamidine derivatives was greater than that of amide derivatives, Ki3005 being the most potent. The vasodepressor effects of cyanoamidine and amide derivatives were antagonized by glibenclamide, although the antagonism of the depressor effects of KRN2391 and nicorandil was less pronounced than that of the other derivatives. These results suggest that N-substituents, in addition to the cyanoamidine structure, play an important role in determining the vasodepressor potencies of 3-pyridine derivatives. Furthermore, the vasodepressor effects of these derivatives appear to be based on their K+ channel-opening actions, although those of KRN2391 and nicorandil seem to be partly mediated by a nitrate-like action in addition to their K+ channel-opening action.

Cardiovascular effects of KRN2391, nitroglycerin and cromakalim in dihydroergotamine-treated pithed rats

1. The effects of KRN2391 on the cardiovascular system were compared with those of nitroglycerin and cromakalim in pithed rats treated with dihydroergotamine (DHE) in order to examine the effects of these drugs on venous blood vessels. 2. DHE (100 micrograms/kg, i.v.) produced increases in mean blood pressure (MBP), cardiac output (CO) and central venous pressure (CVP) without changes in total peripheral vascular resistance (TPR) and heart rate (HR) based on venoconstriction. The DHE-treated pithed rats, nitroglycerin (30 micrograms/kg, i.v.) decreased CO and CVP whereas cromakalim (30 micrograms/kg, i.v.) produced a slight increase in CO followed by a decrease and did not affect CVP. KRN2391 (30 micrograms/kg, i.v.) produced a decrease in CVP without affecting CO. Decreases in MBP and TPR were induced by all drugs. 3. These results suggest that nitroglycerin acts predominantly as a venodilator and KRN2391 and cromakalim showed a venodilating action in addition to an arterial dilating action in DHE treated pithed rats. However, the venodilating action of KRN2391 in this condition is more potent than that of cromakalim.

Antihypertensive and vasorelaxant effects on KRN2391 in spontaneously hypertensive rats

1. In conscious spontaneously hypertensive rats (SHR), the oral administration of KRN2391 (0.1-3.0 mg/kg) produced a dose-dependent decrease in blood pressure. The antihypertensive effect of KRN2391 was about 2 and 20 times more potent than those of pinacidil and nifedipine, respectively, but about 2 times less potent than that of cromakalim. 2. During oral administration of KRN2391 (0.5 and 1.0 mg/kg) once daily for 5 weeks, its antihypertensive effect did not diminish in conscious SHR. 3. In anaesthetized SHR, KRN2391 (3-100 micrograms/kg, i.v.) produced a decrease in blood pressure in a dose-dependent manner. Its antihypertensive effect was antagonized by glibenclamide (20 mg/kg, i.v.). 4. In isolated aorta obtained from SHR, KRN2391 (0.01-100 microM) produced a concentration-dependent relaxation. Its concentration-relaxation curve was shifted to the right by glibenclamide (1 microM) and methylene blue (3 microM). 5. These results indicate that the antihypertensive effect of KRN2391 in SHR is due to its direct action on vascular smooth muscle based on a K+ channel opening action and a nitrate action. In addition, KRN2391 is absorbed from the gastrointestinal tract into blood and does not induce tolerance despite possessing some nitrate action.

Characteristics of Ki1769, a novel vasodilator, in isolated rat aorta

The vasorelaxant mechanism of a newly synthesized vasodilator, Ki1769 [N-cyano-N'-(2-phenethyl)-3-pyridinecarboximidamide], was studied in isolated rat aorta in comparison with cromakalim. Ki1769 (10(-8)-10(-5) M) and cromakalim (10(-8)-10(-5) M) produced a concentration-dependent relaxation and the EC50 values for Ki1769 and cromakalim were (8.60 +/- 1.90) x 10(-7) M and (1.36 +/- 0.18) x 10(-7) M, respectively. Ki1769- and cromakalim-induced relaxations were competitively antagonized by glibenclamide with pA2 values of 6.83 and 6.93, respectively. Charybdotoxin, apamine, atropine, propranolol and indomethacin did not affect the Ki1769-induced relaxation. An increase in 86Rb efflux was induced by Ki1769. Glibenclamide attenuated the increase in 86Rb efflux produced by Ki1769. These results suggest that the vasorelaxant effect of Ki1769 is based on the glibenclamide-sensitive K channel-opening action.

Differential vasodilator properties of KRN2391, cromakalim, nitroglycerin and nifedipine in rabbit isolated femoral artery and vein

1. The selectivity for artery and vein of KRN2391, cromakalim, nitroglycerin and nifedipine was examined in isolated femoral artery and vein preparations of the rabbit. 2. All drugs produced a concentration-dependent relaxation in both femoral artery and vein. 3. Nitroglycerin was more potent in femoral vein than in femoral artery at all concentrations. The EC50 value obtained in the vein was about 14 times smaller than that obtained in artery. 4. Cromakalim and nifedipine were almost equipotent on both vascular preparations. Cromakalim at the highest concentration (10(-5) M) produced 88 and 78% relaxation in femoral artery and vein, respectively. The maximum relaxation induced by nifedipine (10(-6) M) was less than 50% in both preparations. 5. KRN2391 was active at a lower concentration in the vein than in the artery and its maximum relaxation at 10(-5) M was about 90% in both preparations. 6. Glibenclamide (10(-6) M) inhibited the vasorelaxation caused by KRN2391 in both artery and vein. Methylene blue (10(-5) M) also inhibited the relaxant action of KRN2391 but this action was slight in the artery. 7. These results suggest that KRN2391 and nitroglycerin are more potent in the vein than in the artery and cromakalim and nifedipine are equipotent in both. It is considered that the relaxation induced by low concentrations of KRN2391 reflects predominantly its action as a nitrate and that at high concentrations it acts as a K+ channel opener in addition to its nitrate action. The different vascular selectivities of these drugs are thought to relate to the differences in their mechanisms of action in vascular smooth muscle.

Pharmacological analysis of the vasodepressor effect of KRN2391 in pithed rats

1. The antagonism by glibenclamide of the vasodepressor effects of KRN2391, cromakalim and nitroglycerin was compared in pithed rats with blood pressure supported by an infusion of phenylephrine. 2. Cumulative administration of KRN2391 (3-300 micrograms/kg, i.v.), cromakalim (3-300 micrograms/kg, i.v.) and nitroglycerin (1-300 micrograms/kg, i.v.) produced dose-dependent decreases in diastolic blood pressure. 3. In rats given glibenclamide (20 mg/kg, i.v.) the dose-vasodepressor curves for KRN2391 and cromakalim were shifted to the right. However, glibenclamide had no effect on the vasodepressor effect of nitroglycerin. 4. The ED50mmHg values increased about 5.9 fold for KRN2391 and 9.5 fold for cromakalim in glibenclamide-treated rats. 5. These results suggest that the vasodepressor effect of KRN2391 is due to both glibenclamide-sensitive and insensitive mechanisms. This glibenclamide-insensitive effect of KRN2391 is thought to reflect its nitrate action.

Vasorelaxant action of Ki1769, a new pyridinecarboximidamide, in isolated porcine coronary artery

The characteristics of KRN2391 (N-cyano-N'-(2-nitroxyethyl)-3-pyridinecarboximidamide monomethansulfonate) and its phenethyl and 2-hydroxyethyl derivatives (Ki1769 and Ki3315) were studied in isolated porcine coronary arteries. KRN2391, Ki1769 and Ki3315 produced concentration-dependent relaxation of coronary arteries contracted by 25 mM KCl and the order of relaxant potency was KRN2391 > Ki1769 > Ki3315. At the maximum effect, KRN2391 produced nearly complete relaxation but Ki1769 produced about 66% relaxation. The maximum effect of Ki3315 could not be obtained because of its solubility. The relaxation induced by KRN2391 was antagonized by glibenclamide and methylene blue but relaxations caused by Ki1769 and Ki3315 were antagonized by glibenclamide alone. The antagonistic effect of glibenclamide on Ki1769- and Ki3315-induced relaxations was more potent than that on KRN2391-induced relaxation. KRN2391 induced relaxation of coronary arteries contracted by 40 mM KCl in a concentration-dependent manner but the effect of KRN2391 was smaller against 40 mM KCl-induced contractions than against 25 mM KCl-induced contractions. Ki1769 had almost no effect on coronary arteries contracted by 40 mM KCl. These results suggest that pyridinecarboximidamide derivatives which do not possess a nitroxyl group have vasodilating ability based on a K+ channel opening action.

Plasma abnormal prothrombin (PIVKA-II): a new and reliable marker for the detection of hepatocellular carcinoma

We evaluated the clinical usefulness of a protein induced by vitamin K absence, antagonist-prothrombin (PIVKA-II), in detecting hepatocellular carcinoma (HCC) specifically in patients with liver cirrhosis, and the possible correlation between levels of PIVKA-II and pathological features of HCC. Plasma levels of PIVKA-II and alpha-fetoprotein (AFP) were measured in 628 patients with various diseases, including 253 with liver cirrhosis and 116 with HCC. PIVKA-II was detected (greater than or equal to 0.1 arbitrary unit/mL) in 54.3% of HCC and the concentration showed a positive correlation with the tumour size. As a screening test for the detection of HCC, PIVKA-II produced values comparable with those of AFP with a sensitivity, specificity and validity of 52.8, 98.8 and 51.6% respectively. Sixteen of 45 patients (37%) with HCC who had low AFP (less than 100 ng/mL) levels were positive for PIVKA-II. No apparent relationship, however, could be found between the levels of PIVKA-II and the aetiology or pathological findings of HCC. These results suggest that PIVKA-II can be a reliable marker for detecting HCC in patients with liver cirrhosis.

Clinical evaluation of tissue plasminogen activator (t-PA) levels in patients with liver diseases

Tissue plasminogen activator (t-PA) levels in plasma or serum were studied in 416 patients with liver diseases: acute hepatitis (AH, n = 30); fulminant hepatitis (FH, n = 36); chronic inactive hepatitis (CIH, n = 57); chronic active hepatitis (CAH, n = 39); compensated liver cirrhosis (cLC, n = 78); decompensated liver cirrhosis (dLC, n = 84); hepatocellular carcinoma (HCC, n = 64); advanced hepatocellular carcinoma (aHCC, n = 28); and compared with that of a control group (n = 106) of healthy subjects. The t-PA levels showed significant increase in patients with AH, FH, CAH, cLC, dLC and HCC, compared with normal controls. The abnormal rates in t-PA levels (higher than 8.3 ng/ml) for each type of liver diseases were 86.1% in FH, 46.2% in CAH, 50% in cLC, 85.7% in dLC, 67.2% in HCC, and 89.3% in aHCC. t-PA levels tended to be higher in more advanced liver diseases. t-PA levels significantly correlated positively with plasminogen activator inhibitor (PAI-1) in AH, cLC, dLC, HCC and aHCC, and negatively with plasmin alpha 1-plasmin inhibitor complex (PIC), plasminogen (Plg), FDP, AT III and alpha 2-plasmin inhibitor (alpha 2-PI) in dLC, prothrombin time (PT) and fibrinogen (Fbg) in HCC. t-PA levels in patients with FH, CAH and dLC were significantly higher than those in patients with AH, CIH and cLC, respectively. Moreover, the changes of t-PA levels in the clinical courses of various liver diseases revealed that t-PA levels increased sensitively with progression of liver diseases or in advanced liver diseases.(ABSTRACT TRUNCATED AT 250 WORDS)

Solid phase peptide synthesis of human endothelin precursor peptides using two-step hard acid deprotection/cleavage methods

Syntheses are described for the putative human and porcine biosynthetic precursors (hET-38 and pET-39) of endothelin, with the sequence previously deduced from human- and porcine-cDNA coding for preproendothelin. The Boc based solid phase synthetic method was applied, followed by weak hard acid, trimethylsilyl bromide, cleavage. The peptide removal from the resin was optimally accomplished with hydrogen fluoride. Disulfide bridges were formed by air-oxidation, and the linkage modes determined by enzymic (Endoproteinase Asp-N) digestion and HPLC. Five additional C-terminally elongated endothelin homologs were also synthesized. For alternative synthesis of pET-39, the use of trimethylsilyl trifluoromethanesulfonate for the removal of peptide from the resin generated a major side product, which was characterized. hET-38 was found to be less effective in vitro, when compared to endothelin. The vasoconstrictor activity in vitro of other related peptides was comparable to that of hET-38.

Characteristics of KRN2391, a novel vasodilator, compared with those of cromakalim, pinacidil and nifedipine in rat aorta

The characteristics of KRN2391, a novel vasodilator, were studied in rat isolated aorta. The effects of KRN2391, cromakalim, pinacidil and nifedipine on the contractions induced by 20, 40 and 80 mM K+ and by 10(-7) M norepinephrine (NE) were measured first. KRN2391, cromakalim and pinacidil selectively inhibited the contractions induced by 20 mM K+ and NE rather than those induced by high concentrations of K+. Nifedipine could not completely inhibit the NE-induced contractions. The vasorelaxant effect of KRN2391 was inhibited by K+ channel blockers and guanylate cyclase inhibitors. KRN2391, cromakalim and pinacidil increased the 86Rb efflux rate coefficient. Thus, KRN2391 exhibits a vasodilator profile similar to that of the K+ channel openers and induces an increase in 86Rb efflux. It is suggested that opening of the membrane K+ channels may be partly involved in the vasorelaxant mechanism of KRN2391.

Putative precursors of endothelin have less vasoconstrictor activity in vitro but a potent pressor effect in vivo

Endothelin (ET-21) induced a sustained contraction of rat thoracic aortae (EC50 = 2.65 x 10(-10) M) in vitro, and caused a potent pressor effect in vivo after intravenous administration to rats. In contrast, the precursor deduced from porcine cDNA coding ET-21 (pET-39) had 100-fold less contractile activity in vitro (EC50 = 3.26 x 10(-8) M), and so did the precursor from human cDNA (hET-38) (EC50 = 1.48 x 10(-8) M). However, both pET-39 and hET-38 caused almost the same dose-dependent pressor effects as ET-21 in vivo. After intravenous bolus injection at 1 nmol/kg, ET-21 caused an initial transient drop of the arterial pressure, and then induced a gradual pressor effect. On the other hand, hET-38 caused only a gradual rise of the arterial pressure. There may be different mechanism(s) for ET-21 and hET-38 which induce changes in the arterial pressure in vivo.

Assessment in pig coronary artery of long-lasting and potent calcium antagonistic actions of the novel dihydropyridine derivative mepirodipine hydrochloride

Ca antagonistic properties of mepirodipine hydrochloride [+)-(3'S,4S)-3-(1'-benzyl-3'-pyrrolidinyl methyl 2,6-dimethyl-4- (m-nitrophenyl)-1,4-dihydropyridine-3,5-dicarboxylate hydrochloride, YM-09730-5) were assessed by studying the pharmacological actions and binding characteristics of the drug in the stem coronary artery. IC50 values of YM-09730-5 (3.5 x 10(-10) mol/l) and nifedipine (6.6 x 10(-9) mol/l) for 40 mmol/l K-induced tonic contraction of pig coronary artery indicated that YM-09730-5 was about 20 times more potent than nifedipine in Ca antagonistic action. However, YM-09730-5 showed an onset of inhibitory action 3 to 5 times slower than nifedipine. A 40-min preincubation of the target tissue with YM-09730-5 also inhibited the contractions produced by acetylcholine, histamine, 5-hydroxytryptamine, and high Ca, and pD2' values were between 8.0 and 7.0; while nifedipine was less potent. The specific binding of [3H]nitrendipine to the membrane of pig coronary artery was inhibited by YM-09730-5, thereby indicating that [3H]nitrendipine and YM-09730-5 compete for the similar receptor sites of dihydropyridine-sensitive Ca channels. Suppression of high K-, Ca- and agonist-induced contractions by YM-09730-5 (3 x 10(-9) mol/l-10(-7) mol/l) remained even after washings at 20-min intervals for more than 3 h; and, in particular at a high concentration of YM-09730-5, the suppression was slightly antagonized by excess Ca or a Ca-agonist. The contraction inhibited by nifedipine, on the other hand, was readily restored by several washings.(ABSTRACT TRUNCATED AT 250 WORDS)

Demonstration of beta 1-adrenoceptor mediating relaxation of porcine coronary artery by radioligand binding and pharmacological methods

beta-adrenoceptors in the porcine coronary artery were characterized by a radioligand binding assay using (-)-[3H]dihydroalprenolol (DHA) and also by measuring the relaxant response of isolated coronary artery to norepinephrine. Specific (-)-[3H]DHA binding in the porcine coronary artery was saturable, reversible and of high affinity (Kd = 1.6 nM) with a maximal number of binding sites of 63 fmol/mg protein, and it showed a pharmacological specificity as well as stereoselectivity which characterized beta-adrenoceptors. The Hofstee analysis of inhibition of (-)-[3H]DHA binding by atenolol, practolol and ICI 118551 has shown that the averaged concentration of beta 1 and beta 2-adrenoceptors in this tissue was 68% and 32% respectively. The relaxant response of isolated coronary artery to norepinephrine was competitively antagonized by (-)propranolol, (+)propranolol, atenolol, practolol and ICI 118551. The pA2 values of these adrenoceptor antagonists were significantly correlated with the Ki values for beta 1 but not beta 2-adrenoceptors determined by the (-)-[3H]DHA binding assay. Thus, the present study demonstrates that the relaxant response of porcine coronary artery to norepinephrine is predominantly mediated through the stimulation of beta 1-adrenoceptors on vascular smooth muscles.

Usefulness of antithrombin III and alpha 2-plasmin inhibitor in early differentiation of fulminant hepatitis and severe form of acute hepatitis

To evaluate the usefulness of antithrombin III (AT III) and alpha 2-plasmin inhibitor (alpha 2PI) in early differential diagnosis of fulminant hepatitis from the severe form of acute hepatitis, the activities of AT III and alpha 2PI were measured in plasma of 15 patients with fulminant hepatitis and 6 patients with severe form of acute hepatitis. The activities of prothrombin time (PT), hepaplastintest (HPT) and thrombotest (TT) were also evaluated. The mean values and the standard errors (SE) for PT, HPT and TT were 21.1 +/- 2.6%, 14.0 +/- 1.6% and 10.3 +/- 1.7%, respectively, in the early stage of fulminant hepatitis and 25.3 +/- 2.4%, 21.6 +/- 4.6% and 15.8 +/- 3.6%, respectively, in the severe form of acute hepatitis. No significant difference in the tests between these two diseases was noted. On the other hand, the mean values +/- SE for AT III and alpha 2PI were 13.7 +/- 4.6% and 25.6 +/- 8.6% in fulminant hepatitis and 70.2 +/- 28.5% and 98.7 +/- 9.7% in the severe form of acute hepatitis. A significant difference between the two diseases was observed. From the above, it is concluded that measuring AT III and alpha 2PI along with PT, HPT and TT is useful for early diagnosis of fulminant hepatitis.