[Continuous arterial infusion therapy of recombinant interleukin-2 and cyclophosphamide in hepatoma and liver metastasis]

The continuous arterial infusion of only recombinant interleukin-2 (rIL-2) was used in 9 patients with unresectable liver metastasis of colorectal or biliary cancer. This therapy was undertaken for the activation of tumor infiltrating lymphocytes (TIL), but was not effective. Then we tried continuous arterial infusion of rIL-2 and low-dose cyclophosphamide (CY) for liver metastasis. 3 of the patients who received rIL-2 and CY showed partial remission of disease. This therapy was possibly effective because of the activation of TIL and the suppression of tumor infiltrating suppressor lymphocytes.

[Subrenal capsule assay for chemosensitivity test of urinary tract cancers]

Subrenal capsule assay as a chemosensitivity test was performed on 8 renal cell carcinomas and 7 transitional cell carcinomas using athymic mice. Twelve of the 15 trials were considered suitable for evaluable assay. In 2 of the 3 non-evaluable trials the histological examination showed fibroblasts without cancer cells in the implants of the control group while the implants grew macroscopically. No host cell infiltration was observed microscopically in any implant of the control groups of evaluable assays. Mice were treated with several anticancer agents and sensitivities were evaluated by the tumor growth inhibition rate (TGIR) on the day 10 or 12 and by histological changes. No correspondence was observed between TGIR and histological changes. The characteristic histological finding of the treated groups of transitional cell carcinomas was cystic degeneration and it seemed to be a factor of the discordance between TGIR and the histological changes.

[Neurochemical studies on bifemelane, a new cerebral function improver. I. Effects of bifemelane on the function of neurotransmission-related enzymes and receptors in rat brain]

We examined neurochemically the effects of bifemelane (BF) on muscarinic ACh (mACh-R) and beta-adrenergic receptors (beta-AdR) and imipramine binding sites and the activities of acetylcholinesterase (AChE), choline acetyltransferase (CAT) and monoamine oxidase (MAO) in the P2 fractions of rat brain, ex vivo and in vitro. Male rats were given daily injections of 10, 30 mg/kg BF, p.o., for a period of 4 weeks. The Kd and Bmax values for mACh-R in the rat forebrain by administration of 10, 30 mg/kg BF decreased significantly compared with that of the control, although the Kd and Bmax values for beta-AdR and imipramine binding sites were almost identical. The Km and Vmax values of A- and B-form MAO decreased in rats that had been administered 30 mg/kg BF for 4 weeks. The binding of 3H-QNB (quinuclidinyl benzilate) on mACh-R, 125I-CYP (iodocyanopindolol) on beta-AdR and 3H-imipramine on imipramine binding sites decreased by 60, 20 and 70% in the presence of 1 microM BF, respectively, while the addition of 1 microM BF inhibited MAO activity by about 50%. However, CAT and AChE activities were not inhibited by BF.

Simultaneous determination of methamphetamine and its metabolites in monkey urine by gas chromatography/mass spectrometry with selected ion monitoring

A sensitive and specific gas chromatography/mass spectrometry (GC/MS) method has been developed for the simultaneous analysis of methampthetamine and its metabolites (amphetamine, p-hydroxymethamphetamine, and p-hydroxyamphetamine) in monkey urine. The method has been applied to the analysis of urine samples from monkeys singly and repeatedly treated with methamphetamine. We have shown that the repeated administration of methamphetamine causes the reduction of urinary excretion of aromatic hydroxylated metabolites. We propose that the method described here can be used for biological monitoring.

Endogenous monoamine oxidase inhibitor-like substances in monkey brain

The extraction and partial purification of endogenous "monoamine oxidase (MAO) inhibitor-like" material from the monkey brain are described. The endogenous material (F-1 and F-2) obtained after Bio-Gel P-2 gel filtration and silica column chromatography inhibited MAO in the monkey brain mitochondria toward 5-hydroxytryptamine (5-HT), beta-phenylethylamine (beta-PEA), tyramine and dopamine as substrates. The inhibitory effects of F-1 and F-2 were non-linear concentration dependent, and F-1 non-competitively inhibited A-form MAO, while F-2 inhibited A-form MAO competitively and inhibited B-form MAO non-competitively. These substances were more potent inhibitors of A-form than of B-form MAO. F-2 was heat stable but liable to the treatment with pepsin and trypsin. F-1 was not inactivated by heat treatment and digestion with pepsin and trypsin. F-1 may be a low molecular weight (less than 1350) compound, including certain monoamines or their metabolites or other unidentified compounds, while F-2 was a low molecular weight (about 2500) peptide.

Effect of diethylnitrosamine on monoamine oxidase in rat liver

The effect of diethylnitrosamine (DEN), a well-known experimental carcinogen, toward MAO-A and MAO-B activity of rat liver was investigated. The oxidations of both beta-PEA (MAO-B) and 5-HT (MAO-A) were inhibited by DEN. The K1 values of DEN in the inhibition of rat liver MAO-A and MAO-B activity were determined. The kinetic data show that DEN is a competitive, MAO-B selective inhibitor and its inhibitory effect on MAO-B is about 4-fold more potent than that on MAO-A. DEN might change the proportions of the multiple forms of MAO activity in tumor cells.

Changes in amine oxidase in plasma of rats treated with hepatotoxins

When allyl formate (AF) was administered to rats, the marked elevation of B-form MAO activity in plasma was found with beta-PEA as a substrate. In contrast, in the case of carbon tetrachloride (CCl4), A-form MAO activity elevated predominantly. The deaminations of 5-HT and beta-PEA in these plasma treated with AF or CCl4 were not inhibited completely by a high concentration of MAO inhibitor, deprenyl or clorgyline. These results indicate that there may be two or more distinct amine oxidases released from the liver and other organs in response to CCl4 or AF.

Studies on pituitary-gonadal function in patients with Cushing's syndrome

Basal levels of sex steroids, and the responses of LH and FSH to LH-RH were studied in twenty-five female patients with Cushing's syndrome (17 Cushing's disease and 8 adrenocortical adenoma). Only two patients had a regular menstrual cycle. Amenorrhea or oligomenorrhea had been of long duration in the other cases except for three postmenopausal patients. In patients with Cushing's disease, basal estradiol was low or below normal in 86%. Progesterone was normal in 83%, but testosterone was high in half of the cases. The response of LH to LH-RH in patients with Cushing's disease was normal in 35%, low in 35% and high in 29% of the cases. FSH response to LH-RH was normal in 23.5%, low in 23.5% and high in 53%. In patients with adrenocortical adenoma, basal of estradiol was low or below normal, but progesterone and testosterone were normal in all cases. The response of LH and FSH to LH-RH in all patients with adrenocortical adenoma was higher than normal. In three postmenopausal women, a higher response of LH and FSH to LH-RH was seen in two cases and suppressed in one case. These data suggest that the main site of suppression of the gonadal axis in patients with adrenocortical adenoma is the gonad rather than the pituitary gland or hypothalamus, though the mechanism of hypogonadism in patients with Cushing's disease is heterogeneous.

Reversible inhibition of aromatic hydroxylation of methamphetamine in rat liver microsomal preparations pretreated with methamphetamine

The effects of a single and repeated administration of methamphetamine (MP) in vivo in rats on its own metabolism in vitro were investigated. In both cases, the p-hydroxylation of MP to p-hydroxymethamphetamine by a microsomal fraction from rat liver was inhibited for a period of 16 hr after the last injection of MP. This inhibition was diminished by dialysis of the microsomal preparations. In contrast, the reduced level of cytochrome P-450 in hepatic microsomes from rats pretreated with the SKF 525-A did not revert to the control value after dialysis. When microsomes were preincubated with N-hydroxymethamphetamine, which is the metabolite of MP and a potent substrate for the formation of a metabolic intermediate (MI) complex with cytochrome P-450, the content of the MI was increased and the MP-hydroxylation activity decreased in direct proportion to the length of the preincubation. These results suggest that the inhibition of MP-hydroxylation may be due to reduction of the level of cytochrome P-450 that accompanies the formation of the MI complex. Furthermore, it appears that the complex can be dissociated by dialysis.

[A case of renal pseudotumor]

A case of renal pseudotumor in a 47-year old female is reported. She was admitted with the complaint of right flank pain. Intravenous pyelography showed filling defect in right renal pelvis and spreading deformity of calices with compression of infundibuli. Ultrasonography and computed tomography demonstrated round renal mass. Since possibility of hypovascular tumor was not completely ruled out by right selective renal angiography, subsequently performed, then right nephrectomy was done. Bisected specimen revealed mal position of renal lobe (lobar dysmorphism). Microscopic appearance showed normal renal parenchyma. The literature is also reviewed.

Changes in MAO activities in several organs of rats after administration of l-thyroxine

Male rats were given daily injections of 200 micrograms/kg l-thyroxine, s.c., for a period of 10 days. Monoamine oxidase (MAO) activities in the heart, lung and liver mitochondria decreased rapidly to about 50% those of the control rats with 5-HT and beta-phenylethylamine (beta-PEA) as substrates on the first day. After that, heart MAO activity increased gradually and exceeded the control value after 10 days with 5-HT as the substrate. The level of liver MAO activity was maintained at about 50-70% during the same period of administration with 5-HT as the substrate. The thyroxine treated rats showed no marked change in brain MAO activity. In vitro, l-thyroxine and its metabolites had no discriminative actions on MAO activities in these organs of rats. The heart, lung and liver MAO have unaltered Km values for 5-HT and beta-PEA, but decreases in the Vmax for both substrates were observed between the control and l-thyroxine-treated rats. Addition of the brain, heart and liver cytosol fractions from l-thyroxine treated rats caused MAO activities of heart mitochondria to decrease with 5-HT as a substrate and caused them to increase with beta-PEA as a substrate. MAO activities in liver also were inhibited by adding all the cytosols when beta-PEA was the substrate, but on the contrary, lung MAO activities were increased when 5-HT was the substrate. These results indicate the possible presence of multiple modulators of MAO in the cytosol fractions of l-thyroxine treated rats.

Effects of d-methamphetamine on monkey brain monoamine oxidase, in vivo and in vitro

A and B form MAO activities in mitochondria and synaptosome were measured in the brain of monkeys administered d-methamphetamine (d-MP) 2 mg/kg, i.m., daily for 7 days. When mitochondria were used as an enzyme preparation, the Km and Vmax values decreased with 5-HT (serotonin for A-form MAO substrate) and beta-phenylethylamine (beta-PEA for B-form MAO substrate), while in the synaptosome, a significant increase of the Km and Vmax values was observed with 5-HT and dopamine as substrates. The mitochondrial MAO treated with d-MP was inhibited strongly by clorgyline and deprenyl with beta-PEA as a substrate, while synaptosomal MAO was highly sensitive to these MAO inhibitors with 5-HT as a substrate. MP and amphetamine (AP) were found in brain mitochondrial and synaptosomal preparations of monkeys administered 2 mg/kg d-MP, i.m. daily for 7 days; MP and AP contents were 5.05 +/- 0.22 pg/mg protein and 37.3 +/- 3.8 ng/mg protein in mitochondria and 2.35 +/- 0.35 pg/mg protein and 46.4 +/- 1.5 ng/mg protein in synaptosomes, respectively. MAO was inhibited by MP and its metabolites, AP p-hydroxymethamphetamine (OH-MP) and p-hydroxyamphetamine (OH-AP), with 5-HT, beta-PEA and dopamine as substrates, in vitro. MP and its metabolites were more potent inhibitors of A-form MAO than B-form MAO.

[Electrophoretic properties of mitochondrial monoamine oxidase in monkey liver]

Monkey liver monoamine oxidase (MAO) was predominantly the B-form enzyme from the observed differences in substrate specificities and differences in sensitivities to MAO inhibitors. It is known that a MAO inhibitor, pargyline, binds to MAO irreversibly in the molar ratio of 1:1. 3H-pargyline was used as a marker to determine the existence of MAO. The molecular weight of MAO in monkey liver mitochondria was investigated by SDS-polyacrylamide gel electrophoresis after solubilization of 3H-pargyline binding mitochondria with 6% sodium dodecyl sulphate (SDS). The subunit molecular weight was found to be 60,000. The molecular weight determined from the electrophoretic mobility on several concentrations of gels by disc gel electrophoresis in the absence of SDS was found to be 120,000. These results indicate that monkey liver mitochondrial MAO exists as a dimer. Isoelectric focusing of the enzyme after solubilization with 0.1% Triton X-100 and 0.75% Triton X-100 and 0.75% Lubrol showed that it had a pI value near 6.5. Similar pI values were obtained for enzyme preparations solubilized with 0.75% Triton X-100 after treatment with phospholipase A or methylethylketone. These results suggest that the pI value of MAO in monkey liver mitochondria does not depend on the properties of detergents used to solubilize the enzyme preparation.

Interferon producing activity of lymph-node and peripheral blood lymphocytes in cancer patients

The IFN producing activity of RLNL and PBL was studied in cancer patients using K562, PHA-P and OK-432 as inducers. In response to K562, IFN production was significantly greater in the PBL than in the RLNL, and the titer was about equal in the PBL and RLNL when OK-432 was used as an inducer. On the contrary, the amount of IFN produced by PHA-P was significantly higher in the RLNL than in the PBL. There was no definite relationship recognized between tumor progression and IFN productivity in the cases studied.

Evidence for existence of A and B form monoamine oxidase in mitochondria from dog platelets

It is known that platelet MAO appears to behave more like the B-form enzyme than the A-form enzyme based on inhibitor sensitivity and substrate specificity. However, dog platelets showed a different substrate specificity such as high activity with 5-HT and beta-PEA as substrates. Moreover, dog platelet MAO was sensitive to the drugs clorgyline and harmaline with 5-HT as the substrate, while it was sensitive to the drug deprenyl with beta-PEA as the substrate. These results also indicate the existence of two forms of MAO in dog platelets unlike in other platelets such as those from humans. A-form MAO from dog platelets was more stable against heat treatment at 55 degrees C than A-form MAO from dog liver and brain. On the other hand, there was no difference in the heat resistance of the three enzymes with beta-PEA as the substrate. After digestion with trypsin at 37 degrees C for 30 min, it was found that MAO from dog platelets, brain and liver were mostly inhibited with 5-HT as the substrate. In contrast, MAO in brain and liver were inhibited about 10%, but platelet MAO was inhibited about 50% with beta-PEA as the substrate. From these results, it is considered that dog platelet MAO exists as the two forms of the enzyme and has different enzymic properties in comparison with those of MAO from dog liver and brain mitochondria.

Modulation of neuronal MAO activity, 5-HT uptake and imipramine binding by endogenous substances in dog cerebrospinal fluid

Addition of small amounts of dog cerebrospinal fluid (CSF) inhibited both type A and type B monoamine oxidase (MAO) in dog brain mitochondria. The inhibition was competitive with 5-HT as substrate, but non-competitive with beta-phenylethylamine as substrate. Tricyclic antidepressants also exhibited competitive inhibition with type A MAO, but were non-competitive with type B MAO. The endogenous materials in CSF activate [3H]-imipramine specific, dose-dependent binding in dog brain preparations. The maximum number of binding sites (Bmax) increased, but the dissociation constant (Kd) was altered significantly in the presence of CSF. Addition of CSF induced a marked activation of uncompetitive [14C]-5-HT uptake in dog brain preparations. Moreover, there were reversibilities of the inhibition of MAO activity or of the activation of imipramine binding and 5-HT uptake by CSF substance after dilution experiment. These results indicate the possible presence of an endogenous psychotic drug-like substance in CSF.

Increased production of tumor necrosis factor and prostaglandin E2 by monocytes in cancer patients and its unique modulation by their plasma

We investigated the role of monocytes in the production of tumor necrosis factor (TNF) and prostaglandin E2 (PGE2) in 77 cancer patients with malignancies of the digestive tract, using 30 normal individuals and 18 noncancer patients as controls. Monocytes were incubated with lipopolysaccharide for 20 h, and TNF production and PGE2 production were analyzed by bioassays. Elevated levels of TNF (greater than 512 U/ml) and PGE2 (greater than 8 ng/ml) production were demonstrated in many cancer patients when these factors were induced in the medium with 10% fetal bovine serum. The elevated level of TNF was seen to be restricted for the most part to patients with malignancies. Thus, 51 out of 59 cancer patients (86%), consisting of 44 primary cancer patients and 15 recurrent cancer patients, showed an increased level of TNF. In contrast, almost all of 18 postoperative cancer patients showed TNF levels comparable to those of normal individuals. Furthermore, 16 primary cancer patients were also demonstrated to have reduced levels of TNF production by monocytes after curative operation. When 10% cancer-patient plasma was added to the induction culture, TNF production by monocytes was drastically suppressed in the cancer patients. Interestingly, the same addition of plasma induced a prominent enhancement of PGE2 production in the cancer patients. The plasma of noncancer patients did not modulate production of these factors. No TNF activity was found in the plasma of cancer patients, but such plasma did contain an increased level of PGE2 (100-300 pg/ml). Although PGE2 (greater than 2 ng/ml) was able to suppress TNF production by monocytes, the addition of 10% plasma PGE2 was not enough to induce suppression. An unknown factor(s) in the plasma of cancer patients may uniquely modulate the elevated TNF and PGE2 production in these patients.

Effects of food on absorption of mefenamic acid from two commercial capsules differing in bioavailability under the fasting state

The influence of food on the bioavailability of mefenamic acid from two commercial capsules (products A and B) differing in bioavailability was studied with four healthy male volunteers. The drug was administered as a single oral dose of 250 mg under fasting and nonfasting conditions. The study used a 4 X 4 Latin-square design. Seven blood samples were collected over a 9-h period following administration and the plasma concentrations of mefenamic acid were determined by a high performance liquid chromatographical method. The bioavailability was significantly different between the two products in the fasting condition, agreeing with the result of an in vitro dissolution study. However, in the nonfasting state, the difference was not significant because the product showing poor bioavailability, product A, in the nonfasting state showed marked improvement. On the other hand, the product showing good bioavailability, product B, was not affected by food.