Stable Anticonvulsant Action of Benzodiazepines During Development in Rats

Abstract— The anticonvulsant action of midazolam and clonazepam was studied in 168 immature rats in three age groups (12, 18 and 25 days old). Epileptic after-discharges of the spike-and-wave type accompanied by clonic seizures of facial and forelimb muscles induced by stimulation of sensorimotor cortex were used as a model. The solvent used for clonazepam exhibited a tendency to anticonvulsant action in 12-day-old rats. On the contrary, a proconvulsant action was seen in 25-day-old animals. The action of both benzodiazepines was identical and did not change substantially during development. The highest dose used (1 mg kg^?1, i.p.) shortened the duration of epileptic after-discharges, the two lower doses (0·1 and 0·02 mg kg^?1, i.p.) suppressed the progressive prolongation with repeated stimulations seen under control conditions. Motor correlates of stimulation remained practically uninfluenced by the two benzodiazepines, myoclonic seizures accompanying epileptic after-discharges were attenuated by the highest dose of both drugs.     

Fatty acid composition of lipids of Escherichia coli W 1655 F+ and its stable protoplast type L-form

The comparative fatty acid analysis of extractable and non-extractable lipids of Escherichia coli W 1655 F⁺ and its stable protoplast type L-form shows quantitative as well as qualitative differences. From 10 different fatty acids obtained 16:0, 17:0, and 18:0 are present at about the same quantities in the lipid fractions of the bacterial and L-form. The absence of larger amounts of 12:0, 14:0, and 14:βOH fatty acids in non-extractable L-form lipids reflects the loss of the cell wall in L-form cells. 16:1 fatty acid was found in L-form lipids only. This qualitative difference and the 2–3 times higher content of 18:1 in L-form lipids and the 7 times lower content of cyc 19:0 in extractable lipids of the L-form may be interpreted as alterations characteristic for the changed composition of the cytoplasmic membrane in L-form cells.     

Structure and Concentration Capacity of the Kidneys in Brattleboro Rats under Conditions of Long-Term Vasopressin Treatment

Endoprostheses made from knitted fabric of 3 loop types were used for hernioplasty in rats. Biocompatibility of implanted textile constructions was evaluated after 6 months. The intensity of inflammatory reaction and types of complications in animals depended on the loop type and method of finishing of the mesh endoprosthesis tissue. __________ Translated from Byulleten’ Eksperimental’noi Biologii i Meditsiny, Vol. 145, No. 5, pp. 582–587, May, 2008     

Relative Immunogenicity and Tolerogenicity of Individual Regions or Segments of the MHC

Mixed lymphocyte culture (MIX) reactivity, induction of cytotoxicity in vitro, survival of skin allografts, and induction of neonatal transplantation tolerance were compared in mice of the strain combinations differing in the entire H-2 complex or in individual segments of it. The results showed that antigenic products of the K end of the H-2 complex were more immunogenic and also more resistant to tolerance induction than the products of the D end of H-2. I-region products that elicited transplantation reactions of variable strength, depending on the detection system, were relatively easier to overcome in tolerance induction and could, at least in some combinations, contribute to tolerance induction across the barrier represented by the products of the K region of the H-2 complex.     

Role of acid mucopolysaccharides of the kidney in the mechanism of reabsorption of osmotically free water

Histochemical characteristics of acid mucopolysaccharides (MPS) of the renal medulla were compared with the indices of kidney function in dogs during water and osmotic diuresis and polyuria induced by administration of heparin. Changes in staining for MPS were found to correspond to the intensity of reabsorption of osmotically free water. The results suggest that changes in the physicochemical properties of MPS are one of the significant factors determining the permeability of structures of the renal medulla to movement of water from the lumen of the tubules into the interstices.