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L Lachowicz

Publications and source records attributed to L Lachowicz.

At least 37 records · Page 2Linked to original sources
PubMed1994

[Trial for assessment of values: normal, threatening, and pathologic parameters of acid-base equilibrium in umbilical vessel blood and capillary blood in newborns].

A prospective study in 33 newborns infants born spontaneously at term was carried out. First stage labour duration was up to 10 hours while the second one was no longer than 60 minutes. The key criterion for newborns selection from physiological deliveries was a normal heart rate baseline throughout the whole period of labour. Acid-base parameters in umbilical blood vessels and capillary blood were performed on an Blood Analyzer Corning 168. The results allowed to define normal and pathological ranges of the analysed indicators. They may be used for evaluation of newborn's postnatal conditions.

Acid-Base Equilibrium↗
PubMed1994

[Acid-base equilibrium in umbilical blood vessels of fetuses with perinatal hypoxemia symptoms].

The aim of the study was to compare acid-base parameters in umbilical cord blood of fetus from groups with hypoxaemia symptoms and from the control group (physiological deliveries). 111 fetuses were divided into 8 groups. Group I consisted of 33 fetuses with normal heart rate baseline while groups II-VIII involved fetuses from complicated labours with hypoxaemia symptoms. The following characteristics of umbilical vessels blood: low pH, normal or increased PCO2, increased base deficit, low PO2 and PO2 in chronic hypoxaemia were found out. Acute hypoxaemia was characterised by lower pH, high PCO2, normal BE and lower PO2 and SO2.

Acid-Base Equilibrium↗
PubMed1993

Serotonin, histamine and somatostatin modulation of PMA-stimulated phosphorylation of 130 kDa Ca2+ pump-like protein from rat cerebellum synaptosomal membranes.

1. Influence of some neurotransmitters and neuromodulators on the PMA-stimulated phosphorylation in vitro of calcium pump-like protein from rat cerebellum synaptosomal membranes was examined. 2. The prolonged time (up to 6 min) of synaptosomal membranes preincubation with 1 and 10 microM serotonin results in the increase of phosphorylation. The decrease of phosphorylation up to 80% of control value was observed for 100 microM serotonin. 3. The most stimulating effect on 130 kDa protein phosphorylation was observed with 1 microM of histamine (160% of control value). 4. 1 and 0.1 microM somatostatin triggered a short-time transient increase of 130 kDa phosphorylation (up to 135% of control value).

Animals↗
PubMed1992

Characterization of 130 kDa protein from rat cerebellum synaptosomal membranes phosphorylated by PKC.

1. The effect of endogenous PMA-stimulated phosphorylation of the protein in the molecular weight range of 130 kDa in rat cerebellum synaptosomal membranes was examined. 2. The 50% inhibition of the phosphorylation of 130 kDa protein by 5 microM polymyxin B was observed after 6 min of preincubation. 3. The sensitivity of 130 kDa protein for phosphorylation in the presence of exogenous protein kinase C suggests, that this protein could serve as a physiological substrate of protein kinase C. 4. Partial characterization of 130 kDa protein was performed. Upon incubation with [gamma-32P]ATP the 130 kDa protein formed Ca(2+)-dependent, hydroxylamine-sensitive phosphointermediate, which was inhibited by 50 microM vanadate, but not 0.5 mM vanadyl. 5. One-dimensional peptide mapping by proteolysis of 130 kDa protein with V8 protease was obtained.

Animals↗
PubMed1991

The possibility of participation of different protein kinases in the regulation of degradation of Glp6[125I]Tyr8SP6-11 with different endopeptidases in subcellular fractions of rat brain.

1. Nuclear fraction of cortex and synaptosomal fraction of hippocampus of rat brain were preincubated with ATP and different, "second messengers" as well as some "classical" neurotransmitters and then incubated with Glp6[125I]Tyr8SP6-11 (JP). 2. It was found that different neurotransmitters and especially "second messengers" might be involved in the activation or inhibition of peptidase I and II. 3. Activation of different protein kinases results in substantial modulation of degradation of JP (SP C-terminal fragment). 4. The data confirm that products of one peptidase might be inhibitors of the second peptidase acting on JP, although the second enzyme might be affected additionally in conditions activating different protein kinase systems.

1-Methyl-3-isobutylxanthine↗
PubMed1991

Substance P and its fragments affect Ca2+/calmodulin-dependent synaptosomal membrane protein phosphorylation from rat cerebral cortex.

1. We have used synaptosomal membranes to study the influence of substance P and its fragments and analogues of its C-terminal fragment on Ca2+/calmodulin-dependent synapsin I endogenous phosphorylation. 2. SP1-11, SP1-4, [Tyr8]SP6-11 and [pGlu6, Tyr8]SP6-11 at 10(-3) M greatly inhibited synapsin I phosphorylation. 3. SP6-11 at all investigated concentrations and SP1-11, SP1-4, [Tyr8]SP6-11, [pGlu6, Tyr8]SP6-11 at 10(-4) and 10(-5) M were ineffective. 4. The results indicate that SP1-11 and its N-terminal fragment and analogues of its C-terminal fragment act on the phosphorylation of specific synaptic protein (synapsin I) and therefore may influence the release of neurotransmitters, membrane conductance and potentiation or inhibition of other signalling systems.

Animals↗
PubMed1990

Effects of N- and C-terminal fragments of substance P on ATPase and monoamine oxidase activities in rat brain.

The in vitro influence of substance P (SP) C- and N-terminal fragments on the Na+,K(+)-ATPase and Ca2+,Mg2(+)-ATPase and monoamine oxidase (MAO) from synaptosomal membrane and extra-synaptosomal mitochondria were studied. The obtained results indicate: 1. C-terminal fragment of SP (SP6-11) in 10 microM concentration stimulates the Ca2+,Mg2(+)-ATPase activities from cerebral cortex and hippocampus. Na+,K(+)-ATPase from cerebral cortex is hardly sensitive to the action of this fragment. 2. N-terminal fragment of SP (SP1-5) in 10 microM concentration increases Na+,K(+)-ATPase activity from cerebral cortex and hippocampus. 3. N-terminal tetrapeptide (SP1-4) exerts no influence on ATPases independently from their brain localization. 4. The activity of monoamine oxidase after use of C- and N-terminal fragments is unchanged.

Adenosine Triphosphatases↗
PubMed1990

The influence of substance P and its fragments on endogenous phosphorylation of synaptosomal membrane protein (synapsin) from cerebral cortex of rat brain.

1. The effects of substance P and its fragments and analogue of a C-terminal fragment on cyclic AMP-dependent phosphorylation of synapsin I in synaptosomal membranes (SM) from cerebral cortex were investigated. 2. SP(I-II) and SP(1-4) at 10(-3) M caused a marked stimulation of synapsin I phosphorylation. 3. A C-terminal fragment of SP (SP6-11) had no effect on phosphorylation of synapsin 1. 4. Analogue of C-terminal fragment [(Tyr8)SP6-11] at 10(-3) M distinctly inhibits phosphorylation of synapsin I. 5. These data suggest that SPI-II and its C- and N-terminal fragments have a modulator function against the phosphorylation of some rat brain proteins.

Animals↗
PubMed1990

The effect of the typical peptidases (proteases) inhibitors on the degradation of Glp6 (125I) Tyr8SP6-11 hexapeptide in the nuclear and synaptosomal fraction of the cortex and hippocampus of rat brain.

The main peptidase PN/cutting Tyr8-Gly9 or Gly9-Leu10 bond (of sequence Glp6-Phe7-Tyr8-Gly9-Leu10-MetNH2) seems to be, at least in part, cysteine type enzyme. Cutting of Phe7-Tyr8 bond with PC enzyme is apparently negligible. Further degradation of labelled PN products seems to be accomplished with PI, being serine enzyme at least in part. Metalloenzymes, including "enkephalinase", seem to be of minor importance in hexapeptide degradation, at least in its very low concentration. Some typical inhibitors enhance the degradation what might be explained assuming that products of action of one peptidase strongly inhibit the other peptidase's action. Namely, products of PN and PI seem to inhibit PC except the hippocampal synaptosomes where the opposite is true.

Animals↗
PubMed1990

[24-hour fluctuations of the values of certain components of the saliva and dental plaque in school children].

24-hours changes were studied in the saliva and dental plaque of the concentrations of total fluorine, inorganic phosphate and protein, and of pH value. The study was carried out in two groups of school children: I--control, II--subjected to contact fluoridation. The obtained results showed that circadian changes occurred in controls and in children subjected to fluoridation.

Child↗
PubMed1989

[Calcium magnesium ATPase activity in homogenates of the placenta and myometrium of pregnant women and parturients].

The authors determined total and specific activity (Ca2+, Mg2+) ATPase in homogenates of uterus muscle, placenta, amnion and chorion. The material was also studied for the levels of ATP, ADP and AMP in order to evaluate the energetic potential. The research was carried out in two groups: among 23 pregnant women who underwent Cesarean section not accompanied by labour pains and among 30 women in labour in whom labour pains lasted up to six hours and then labour was completed by Cesarean section. It was found that in advanced pregnancy the highest enzyme activity is in chorion homogenates. Labour pains result in decrease in enzyme activity in the material studied; the highest significant decrease observed in chorion. It was also found that labour pains do not result in greater changes in energetic potential of tissues except for chorion and amnion. The results obtained point to particular participation of chorion in the process of active transportation of calcium ions in pregnancy and delivery. The consequence of change in enzyme activity will be changes in the level of Ca2+ ions, which will result in the activation or inhibition of various metabolic tracts on cellular level, including hormonal changes.

Ca(2+) Mg(2+)-ATPase↗
PubMed1987

A comparison of the effects of substance P and shorter analogues on the synaptosomal ATPases activities in the rat brain.

The influence in vitro of SP and C-terminal fragments of analogues SP(5-11) (pyroGlu5, Tyr8); SP(6-11) (pyroGlu6, Tyr8); SP(6-11) (pyroGlu6, D-Phe7); SP(6-11) (pyroGlu6, D-Phe8) on the (Ca, Mg) and (Na, K) ATPases activities from synaptosomal membranes of cerebral cortex and hippocampus of rat brain were compared. The data obtained in this study indicate the following: 1. Substance P stimulates the activities of (Na, K) and (Ca, Mg) ATPases more effectively in synaptosomal membranes from hippocampus than cerebral cortex. 2. Heptapeptide SP(5-11) (pyroGlu5, Tyr8) causes a more distinct increase of (Ca, Mg) ATPase activity in cortical synaptosomal membranes than SP does. 3. The change of L-Phe conformation to D in position 7 in hexapeptide induces reduction of enzymes activities in hippocampus. 4. Especially important for the maintenance of biological activity of drugs is the replacement of Gln5 with pyroGlu6 and conformation of Phe residues. 5. SP and shorter analogues of fragments SP C-terminal SP regulate the active cation transport in synaptosomal membranes of cerebral cortex and hippocampus.

Adenosine Triphosphatases↗
PubMed1987

The effects of the main body cations on the peptidase(s) activity against pyroGlu6[125I-Tyr8]SP6-11 in the nuclear and synaptosomal fraction of the cortex and hippocampus of rat brain.

1. Peptidase(s) activity of nuclear and synaptosomal fraction from cortex and hippocampus of rat brain against pyroGlu6[125I-Tyr8]SP6-11 was evaluated in different concentration of Ca2+, Mg2+, K+ and Na+ in about "isotonic" conditions. 2. The effects of studied ions on the peptidase activities forming N-terminal and C-terminal fragments are different especially in synaptosomes of both areas. 3. The differences of ionic requirements for N- and C-forming activities are particularly relevant for Ca2+ at the cortex and K+ at the hippocampus. 4. Ca2+ activate forming of N-terminal fragments in the nuclear fraction whereas inhibit it in synaptosomes from both areas. 5. The ionic requirements for C-terminal fragments' formation in synaptosomes of both areas are contradictory.

Animals↗
PubMed1986

Effects in vitro of L-glutamate and kainic acid on the ATPase activities of synaptosomal membranes from different areas of rat brain.

Changes in the activities of enzymes responsible for the active transport of Na+, K+, Ca2+, Mg2+ in synaptosomal membrane (SM) preparations from the cerebral cortex, hippocampus and thalamus with hypothalamus after incubation with L-glutamate (Glu) or kainic acid (KA) were investigated. Glu stimulated Ca,Mg- and Na,K-ATPase activities in cortex but reduced the activities of all the investigated ATPases, except Na,K-ATPase in the hippocampus and thalamus with hypothalamus. KA reduced distinctly the activity of ATPases in the cortex and only slightly in the thalamus with hypothalamus, but stimulated the enzyme activities in the hippocampus. Both, Glu and KA in vitro altered the processes of active transport of cations in SM preparations.

Adenosine Triphosphatases↗