Effect of nicergoline on learning and memory

The anti-amnestic action of nicergoline was studied using the following experimental methods for learning and memory impairment, based on passive avoidance response: amnesia induced by maximal electroshock in mice, scopolamine-induced amnesia in mice and amnesia by paradoxical sleep deprivation in rats. Piracetam, meclofenoxate, pyritinol, deanol and phenazepam were used as reference drugs. The results show that nicergoline demonstrates well-expressed anti-amnestic effect manifested by reducing the amnestic effect of maximal electroshock, scopolamine or paradoxical sleep deprivation, its effect being equal to or more pronounced than piracetam, meclofenoxate, pyritinol, deanol and phenazepam.     

Sensitivity to hypobaric hypoxia in mice selected for high and low brain weights

We studied the effect of hypobaric hypoxia on mice with various brain weights. Mice with low brain weight were more resistant to hypoxia than animals with high brain weight.     

Dietary polyamines promote the growth of azoxymethane-induced aberrant crypt foci in rat colon

We have examined whether dietary polyamines influence the formation and initial growth of azoxymethane (AOM)-induced aberrant crypt foci (ACF) in rat colon. Effects of a combination of dietary polyamines at three dose levels (putrescine: 50, 280, 740 nmol/g; spermidine: 10, 261, 763 nmol/g; spermine: 1, 31, 91 nmol/g) in the polyamine-poor AIN-76A diet were studied in animals in two different experimental situations: animals treated with AOM alone and animals treated with AOM + difluoromethylornithine (DFMO), a specific inhibitor of endogenous polyamine synthesis. In both experimental situations, dietary polyamines enhanced the growth of ACF, expressed as the number of large ACF (foci with three or more aberrant crypts, ACF > or = 3), whereas the formation of ACF, expressed as the number of ACF, was apparently not altered. In animals treated with AOM alone, maximal growth enhancing effect on ACF was nearly obtained with the median level of dietary polyamine. In rats fed a low polyamine diet, basic AIN-76A, DFMO reduced the growth of AOM-induced ACF by 83%. This inhibitory effect of DFMO was counteracted by dietary polyamines in a dose- dependent manner, and it was abolished at the highest level of polyamines. In conclusion, it was demonstrated that dietary polyamines are able to enhance the growth of AOM-induced ACF. Further, dietary polyamines reversed the DFMO-caused inhibition of ACF growth, probably by compensating for the DFMO-reduced endogenous polyamine synthesis.      

Comparativein vitro study of the effect of contrast media on complement activity and eicosanoid content in rat blood

The study comparesin vitro effect of different contrast media on complement activity and eicosanoid content. Ionic agents (Bilignost>Iodamide>Triombrast>Hexabrix) exert pronounced complement-activating effect, while nonionic agents markedly increase blood content of arachidonic acid metabolites. The complement-activating effect of contrast media did not correlate with their ability to elevate blood content of prostaglandin F_2α and leukotrienes C₄ and B₄. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 125, No. 6, pp. 637–640, June, 1998     

Studies of Learning and Memory Processes in Adult Rats in Conditions of Intracerebral Administration of Caspase Inhibitors

The effects of caspase inhibitors on different types of learning and memory were studied in adult rats on administration into the cerebral ventricles and application to the vermis of the cerebellum. The wide-spectrum caspase inhibitor z-VAD-fmk, given into the lateral ventricles of adult rats, facilitated the formation of long-term spatial memory in a water maze and increased the ability to rearrange the habit at the early stages of acquisition of this skill. Application of the specific caspase 3 inhibitor z-DEVD-CHO to the cerebellar vermis stimulated the extinction of an acoustic startle reaction but had no effect on its retention or reproduction. These results indicate that caspases may be involved in the mechanisms of learning and memory both via indirect influences on the linked processes of neurogenesis and apoptosis in the adult brain and by regulating synaptic efficiency. Translated from Rossiiskii Fiziologicheskii Zhurnal imeni I. M. Sechenova, Vol. 94, No. 4, pp. 361–370, April, 2008.