Plasma pharmacokinetics and tissue distribution of L-lysine α-oxidase from Trichoderma cf. aureoviride RIFAI VKM F- 4268D in mice.

L-lysine α-oxidase (LO) is an L-amino acid oxidase with antitumor, antimicrobial and antiviral properties. Pharmacokinetic (PK) studies were carried out by measuring LO concentration in plasma and tissue samples by enzyme immunoassay. L-lysine concentration in samples was measured spectrophotometrically using LO. After single i.v. injection of 1.0, 1.5, 3.0 mg/kg the circulating T1/2 of enzyme in mice varied from 51 to 74 min and the AUC0-inf values were 6.54 ± 0.46, 8.66 ± 0.59, 9.47 ± 1.45 µg/ml × h, respectively. LO was distributed in tissues and determined within 48 h after administration with maximal accumulation in liver and heart tissues. Mean time to reach the maximum concentration was highest for the liver-9 h, kidney-1 h and 15 min for the tissues of heart, spleen and brain. T1/2 of LO in tissues ranged from 7.75 ± 0.73 to 26.10 ± 2.60 h. In mice, plasma L-lysine decreased by 79% 15 min after LO administration in dose 1.6 mg/kg. The serum L-lysine levels remained very low from 1 to 9 h (< 25 µM, 17%), indicating an acute lack of L-lysine in animals for at least 9 h. Concentration of L-lysine in serum restored only 24 h after LO administration. The results of LO PK study show that it might be considered as a promising enzyme for further investigation as a potential anticancer agent.

Encapsulation of PEG-urease/PEG-AlaDH enzyme system in erythrocyte.

No intravenously injectable enzyme preparate containing urease as an alternetive to hemodialysis, hemoperfusion and CAPD systems in patients having chronic renal failure has been encountered in literature. In this study, it has been aimed to convert blood urea to alanine by using PEG-urease/PEG-AlaDH enzyme pair encapsulated within living erythrocyte. In this system, urea is decomposed into NH3 and HCO3- and the ammonia released is converted into alanine by reacting pyruvate under the catalytic action of alaninedehydrogenase. The production of pyruvate and NADH by erythrocyte required in the second stage of the reaction will make the process a feasible and ceaseless one. The success of the system will enable the renal patients with diabetes mellitus. Urease and AlaDH were covalently immobilized on activated PEG. PEG-urease/PEG-AlaDH were encapsulated in erythrocyte (1/1)(v/v) by using slow dialysis methods. The activity of enzyme system, encapsulation yield and hemogram analysis were determined for each sample.

[Distribution, structure and transmitter content of nerve elements affecting the function of Oddi's sphincter]. / A musculus sphincter Oddi müködését befolyásoló idegelemek megoszlása, szerkezete és transmitter tartalma.

Nerve elements containing neuropeptides were observed by using different antisera and Avidin-Biotin-Peroxidase technique and the distribution of nicotinamide adenine dinucleotide phosphate-diaphorase (NADPH-d), a marker for nitric oxide (NO) synthase were studied in the ampulla hepatopancreatica (sphincter of Oddi) in the cat. A large amount of NPY, VIP, Substance P, somatostatin immunoreactive nerve fibers were found in all layers. Some immunoreactive nerve cell bodies (NPY, VIP, SP), were also observed in the wall. The NADPH-d stained cell bodies could be distinguished according to their size and the number of processes into two neuronal subtypes: large neurons with many dendrites and smaller, round cells with one or two processes. 99% of the cell bodies showed pozitive reactions for NADPH-d. The nerve fibers with NADPH-d activity were found in all layers, chiefly in the muscle layers. According to the distribution of the nerve fibers and the relationship to the effector cells, it is suggested, that these neuropeptides might have an important role in the function, and the NO containing nerve fibers are responsible for the nonadrenergic and noncholinergic inhibitory function.