Germination of basidiospores of Agaricus bisporus

The type of dormancy and conditions necessary for germination of Agaricus bisporus basidiospores (BS) were studied. BS failed to germinate on starvation agar and required the presence of carbon and nitrogen (asparagine and/or glucose) sources in the medium. Upon 3-week storage, BS germinated after 4-5 days. Heat shock (20 min at 45 degrees C) and the decreased temperature facilitated activation of germination. Heterocyclic compounds stimulating germination of endogenously dormant spores, such as furfural, failed to activate germination. The data obtained suggested an endogenous dormancy of A. bisporus BS differing from zygospores of Mucorales. BS contained 17-19% lipids with a composition of fatty acids differing from those of pileus and stipe of the fruiting body. The soluble carbohydrates of the cytosol amounted to 12% dry spore weight and consisted of mannitol (74%) and trehalose (26%). Unlike BS stored at 2 degrees C, the BS stored for 5 months at 20 degrees C lost their ability to germinate, which correlated with a decrease in the content of trehalose.     

Relationship between the molecular structure of nitrogen source and the activity of the extracellular lectins of Lentinus edodes (Berk.) Sing [Lentinula edodes (Berk.) Pegler] upon submerged cultivation

The activity of the extracellular lectins of Lentinus edodes (Berk.) Sing [Lentinula edodes (Berk.) Pegler] and the formation of a pigmented mycelial film by this fungus upon submerged cultivation in a synthetic medium were found to depend on the presence of some amino acids (particularly, asparagine) and Ca2+ and Mn2+ ions in the medium. Quantum chemical calculations suggest that the different character of the interaction of amino acids with the aforementioned ions is due to differences in the hydrophobicity of the amino acids rather than to differences in the electron structure of the amino acid zwitterions.     

A permanent magnetic field alters the phospholipase activity in the snake venom from Vipera lebetina

It was found that at the exposure of Vipera lebetina snakes (during 10 days for 30 min daily) to SMF (0.15 T1) the specific activity of venom phospholipase A1, A2 and phosphodiesterase C increased by 20.6 +/- 2.8; 31.7 +/- 3.2 and 32.7 +/- 1.3% correspondingly. The above mentioned changes of venom enzyme activity were accompanied with the decrease of its total protein amount by 31.6 +/- 2.2%. It could be supposed that the described changes are able to cause significant changes in the total metabolic activity of cells and the organism as a whole.     

Hemagglutinating activity of the fungusLentinus edodes (Berk.) sing [Lentinus edodes (Berk.) Pegler]

The hemagglutinating (HA) activity of the submerged mycelium and the culture liquid (CL) of four strains ofLentinus edodes was studied. The HA activity of the CLs proved to be much higher than that of mycelia. The carbohydrate specificity of fungal agglutinating factors was determined. HA activity was investigated as a function of the inoculum size, cultivation temperature, and culture age. The agglutinating activity of different morphogenetic structures ofL. edodes F-249, including mycelium, brown mycelial mat (MM), primordia, and fruiting bodies, was studied. MM was found to possess the maximum HA activity, which can be explained by the possible involvement of agglutinins in the formation of MM, which is composed of glued hyphae.     

Onset of a dissociative state--reversible amnesia as affected by phenazepam

Dissociation is produced by injections of phenazepam (a benzodiazepine tranquilizer) before daily sessions of rat learning in a T-maze. The drinking reflex is seen only after the administration of benzodiazepine. The dissociation depth is linked with the dose of phenazepam: the higher the dose the more pronounced dissociation. Besides, it depends on the time between the administration of phenazepam and the reflex registration. One may assume that learning in the presence of phenazepam gives rise to new interrelations that form the basis for a new functional system which warrants the activity with the drug in the body.     

Role of GABA-ergic and dopaminergic mechanisms in the withdrawal syndrome after discontinuation of long-term phenazepam administration

It has been shown that depakin, a GABA-ergic agonist, and alpha-methyl-DOPA that inhibits catecholamine synthesis are capable of removing the withdrawal syndrome (disturbed pavlovian behavior pattern and aggressiveness) occurring after discontinuance of long-term administration (30 days) of phenazepam to rats in a dose of 2 mg/kg. In contrast, bicucullin, a blocker of GABA-ergic receptors, thiosemicarbazide that inhibits GABA synthesis by the brain, disulfiram and 3,4-dioxyphenylalanine that increase dopamine and noradrenaline content in the barain aggravate the withdrawal syndrome after phenazepam is discontinued. The data obtained suggest a role of GABA-ergic and dopaminergic mechanisms in the emergence of the withdrawal syndrome after discontinuance of long-term administration of benzdiazepins.     

Role of the GABA- and cholinergic systems in the formation of a dissociated state to an antioxidant of the 3-hydroxypyridine class

The experiments on rats have shown that the elaboration of conditioned drinking reflex in T-maze during administration of 2-ethyl-6-methyl-3-hydroxypyridine antioxidant with an anti-stress effect was accompanied by the development of state dependent learning. However, its formation was slower, as compared to state dependent learning in response to the known psychotropic drugs. The replacing test with the injection of bicuculline, picrotoxin, Ca valproate, Ro-15-1788, benactyzine, Cleregil, etc. during state dependent learning made it possible to establish the role of GABA and cholinergic systems in the formation of state dependent learning and in the development of disorders in emotional behavioural reactions after long-term administration and withdrawal of 3-hydroxypyridine.