Synthesis of 21-esters of hydrocortisone with glycine and glutamic acid and study of their pharmacological activity

Translated from Khimiko-farmatsevticheskii Zhurnal, Vol. 24, No. 3, pp. 26–29, March, 1990.     

Morphological signs of restitution in the caudate nucleus after amphetamine excitation

A light- and electron-microscopic study was made of changes in the structure of neurons and synapses in the caudate nucleus of rats 2 and 3 days after motor excitation induced by amphetamine (10 mg/kg body weight). Electron-microscopic investigations 2 days after amphetamine excitation showed predominance of synthesis over utilization of the intracellular organelles in the neurons of the caudate nucleus; the latter process took place, moreover, in the direction from nucleus to periphery of the cell body. A statistically significant increase in the mean area of cross-section of the nuclei and bodies of the neurons and in the number of impregnated spines per unit length of the dendrites was found. The ultrastructure of the neurons was largely restored to normal after 3 days although the mean area of cross section of the bodies and nuclei of the neurons had not yet reached its initial values. There was virtually no difference in the number of impregnated spines of the dendrites compared with the control, but electron microscopy revealed many synaptic vesicles in the axon terminals.     

Effect of different factors modifying the activity of some enzyme systems of the endoplasmic reticulum on the sensitivity of cell organelles against the damaging action of chemical agents. II. Studies with chlorpromazine, 2,4-dinitrophenol, phenobarbital and DDT.

Further investigations on the effect of different stress factors on the stability of intracellular membranes were carried out. Large granule fractions derived from livers of sleep-deprived and dehydrated rats and subjected to preincubation at 37 degrees and pH 5 were shown to release latent acid phosphatase with a delayed rate indicating an increased lysosomal stability towards acid media conditioning. Lysosomes of such animals, however, were found to be more sensitive to mechanical treatments (homogenization procedure in this case) than that of controls, a conclusion made on the basis of enhanced "free" and nonsedimentable phosphatase activities in liver homogenates. The stress factors which previously were included in the group of modifiers of the activity of the endoplasmic reticulum-located enzymes caused some changes in the action of certain chemicals on membranes. Earlier such changes were elicited for carbon tetrachloride and only on low-temperature-conditioned rats for chlorpromazine. The present results show that stress factors studied result in deviations (different in extent and in direction) from the usual effects of chlorpromazine, 2,4-dinitrophenol, phenobarbital and DDT on liver lysosomes and peroxisomes.     

Influence of neonatal short-term reduction in brainstem alpha2A-adrenergic receptors on receptor ontogenesis, acoustic startle reflex, and prepulse inhibition in rats

Neonatal treatments can disrupt prepulse inhibition (PPI) of startle response later in life. Alpha2A-adrenergic receptors (alpha2A-ARs) regulate the release of brain neurotransmitters that may influence PPI. The authors examined the effects of short-term reduction in the neonatal brainstem alpha2A-ARs on subsequent development of this receptor system and acoustic startle reflex in rats. Administration of antisense oligodeoxynucleotide complementary to the alpha2A-ARs on Days 2-4 of life reduced receptor expression in the brainstem by Day 5. The treatment increased alpha2-AR numbers in the cortex, hippocampus, and amygdala at 40 days of age, and in cortex and hypothalamus at 90 days of age. Transient increases in hippocampal and amygdalar alpha2-ARs were accompanied by attenuation of acoustic startle response and impairment of PPI.     

Immuno- and phagocytosis-modulating properties of low doses of B1-aflatoxin and benzene

Benzene or benzene-dissolved B₁-aflatoxin in low doses promotes an increase of the Thy-1⁺ cell count in the bone marrow of mice and an enhancement of the thymusdependent immune response.In vitro aflatoxin and benzene are unable to induce the expression of Thy-1-antigen in bone marrow T-precursors. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 117, N ^o 2, pp. 158–160, February, 1994 Presented by S. A. Neifakh, Member of the Russian Academy of Medical Sciences     

Prolonged action of tuftsin on penicillin-induced epilepsy

Brain Research Institute, Russian Academy of Medical Sciences, Moscow. Institute of Biological Research, Belgrade, Yugloslavia. Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 114, No. 7, pp. 56–58, July, 1992.     

Role of adrenoreceptors of Ehrlich's ascitic carcinoma in the regulation of proliferative processes by adrenergic ligands

Two categories of specific binding sites for the β-adrenergic ligand³H-dihydroalprenolol have been revealed on the cells of Ehrlich's ascitic carcinoma. The synthesis of DNA in the tumor cell culture possessed different sensitivities to α- and β-adrenergic preparations. Propranolol, a β-adrenoblocker, suppressed DNA synthesis most intensively in concentrations approaching the therapeutic ones. It is hypothesized that β-adrenoreceptors participate predominantly in the regulation of proliferative processes in Ehrlich's ascitic carcinoma by adrenergic ligands. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 120, N^no 11, pp. 525–528, November, 1995