scholarly journals Purification and properties of esterases characteristic of adult rat brain

1968 ◽  
Vol 110 (4) ◽  
pp. 713-719 ◽  
Author(s):  
Danica Dabich ◽  
Bhargavan Chakrapani ◽  
Frank N. Syner

1. A method for the partial purification of an esterase fraction, present in the brain of the adult but not the newborn rat, is described. A 54-fold purification was achieved in three steps. 2. When subjected to starch-gel electrophoresis, the purified fraction resolved into three bands of esterase activity. Two of these bands migrate close together and faster than other esterases in the brain. These two esterases are inhibited by p-hydroxymercuribenzoate but not by di-isopropyl phosphorofluoridate. The third band is di-isopropyl phosphorofluoridate-sensitive and migrates just behind the two leading esterases. 3. After treatment with di-isopropyl phosphorofluoridate, to obviate the effects of the di-isopropyl phosphorofluoridate-sensitive esterase, the enzyme preparation hydrolyses α-naphthyl acetate, α-naphthyl propionate and α-naphthyl butyrate, but not cholesteryl acetate. The Vmax. for the naphthyl esters decreased with increase in chain length of the acyl group. The acetate ester is hydrolysed 34 times as fast as the butyrate and about seven times as fast as the propionate derivative. The Km values for these three esters, measured at pH7·2 and 37°, are 2·8×10−4m, 3·1×10−4m and 7·3×10−5m for the acetate, propionate and butyrate derivatives respectively. 4. The Hofstee (1952) plots for the kinetic data show a single line, indicating that the two most-rapidly migrating esterases, although electrophoretically separable, are not kinetically distinguishable in the substrate ranges examined.

Author(s):  
А. М. Романюк ◽  
Г. Ю Будко

ОСОБЛИВОСТІ МАСОМЕТРИЧНИХ ПОКАЗНИКІВ ТА МОРФОЛОГІЧНИХ ЗМІН ГОЛОВНОГО МОЗКУ СТАТЕВОЗРІЛИХ ЩУРІВ В УМОВАХ ВПЛИВУ НА ОРГАНІЗМ СУЛЬФАТІВ МІДІ, ЦИНКУ ТА ЗАЛІЗА - З метою вивчення масометричних показників щурів та їх головного мозку за умов довготривалої дії (упродовж 90 діб) на організм сульфатів міді, цинку та заліза було проведено експеримент на 48 білих статевозрілих щурах-самцях масою 200-250 г віком 5-7 місяців. Застосовували анатомічні, статистичні та загальноприйняті методики мікроанатомічного методу дослідження. Встановлено, що комбінований вплив на організм сульфатів міді цинку та заліза чинить на головний мозок досить виражений токсичний ефект, що негативно позначається на масометричних показниках загальної маси щурів та маси головного мозку. Це свідчить про розвиток у головному мозку явищ гострого набряку з ознаками геморагічної інфільтрації. Ступінь вираження набряку зростає та досягає максимальних показників наприкінці експерименту.<br />ОСОБЕННОСТИ МАСОМЕТРИЧЕСКИХ ПОКАЗАТЕЛЕЙ И МОРФОЛОГИЧЕСКИХ ИЗМЕНЕНИЙ ГОЛОВНОГО МОЗГА ПОЛОВОЗРЕЛЫХ КРЫС В УСЛОВИЯХ ВОЗДЕЙСТВИЯ НА ОРГАНИЗМ СУЛЬФАТОВ МЕДИ, ЦИНКА И ЖЕЛЕЗА - С целью изучения масометрических показателей крыс и их головного мозга в условиях длительного действия (в течение 90 суток) на организм сульфатов меди, цинка и железа был проведен эксперимент на 48 белых половозрелых крысах-самцах массой 200250 г в возрасте 5-7 месяцев. Применялись анатомические, статистические и общепринятые методики микроанатомического метода исследования. Установлено, что комбинированное воздействие на организм сульфатов меди и цинка и железа оказывает на мозг достаточно выразительный токсический эффект, что отрицательно сказывается на массометрических показателях общего веса крыс и веса головного мозга. Это свидетельствует о развитии в головном мозге явлений острого отека с признаками геморрагической инфильтрации, степень выраженности которого максимальна в конце эксперимента.<br />FEATURES OF MASS INDICES AND MORPHOLOGICAL CHANGES IN ADULT RAT BRAIN UNDER THE INFLUENCE ON THE BODY OF COPPER SULFATE, ZINC AND IRON - To study the performance of rats and their mass brain in long acting (for 90 days) on the body of copper sulfate, zinc and iron, an experiment was conducted on 48 white adult male rats weighing 200-250 gram, aged 5-7 months. There was applied anatomy, statistics and conventional techniques microanatomical research method. It was established that the combined effect on the body of copper and zinc sulphates and iron in the brain has enough expressive toxicity, which affects performance on the total weight of the rats and brain weight. This testifies to the development of brain edema, acute phenomena with signs of hemorrhagic infiltration. The severity of edema increases and reaches maximum performance at the end of the experiment.<br />Ключові слова: головний мозок, солі важких металів, відносна маса, коефіцієнт цефалізації.<br />Ключевые слова: головной мозг, соли тяжелых металлов, относительная масса, коэффициент цефа- лизации.<br />Key words: brain, salts of heavy metals, relative mass, ratio cephalization.


1974 ◽  
Vol 52 (1) ◽  
pp. 273-275 ◽  
Author(s):  
José A. Ferrer-Monge

The esterase isozyme patterns for irradiated and non-irradiated soybean seed and seedlings were determined by starch gel electrophoresis. Patterns were determined for cotyledons, hypocotyl, epicotyl, first pair of leaves, and roots. Two different esterase systems, E1 and E2, were detected by using appropriate substrates. E1 produces three anodic bands with both α- and β-naphthyl acetate. E2 acts only on α-naphthyl acetate producing three cathodic bands. Radiation did not change the patterns. Results indicate that esterase isozymes are more abundant in the aerial than in the underground portion of developing seedlings.


1991 ◽  
Vol 57 (4) ◽  
pp. 1112-1118 ◽  
Author(s):  
Alberto Alcázar ◽  
M. Elena Martín ◽  
Ana García ◽  
Juan L. Fando ◽  
Matilde Salinas

2013 ◽  
Vol 65 (1) ◽  
pp. 255-264
Author(s):  
Natasa Loncarevic-Vasiljkovic ◽  
Vesna Pesic ◽  
N. Tanic ◽  
Desanka Milanovic ◽  
Aleksandra Mladenovic-Djordjevic ◽  
...  

The recovery period following cortical injury (CI) is characterized by a dynamic and highly complex interplay between beneficial and detrimental events. The aim of this study was to examine the expressions of Glial Fibrillary Acidic Protein (GFAP), Apolipoprotein E (ApoE) and Amyloid Precursor Protein (APP), all of which are involved in brain plasticity and neurodegeneration. Our results reveal that CI strongly influenced GFAP, ApoE and APP mRNA expression, as well as GFAP and ApoE protein expression. Considering the pivotal role of these proteins in the brain, the obtained results point to their potential contribution in neurodegeneration and consequent Alzheimer?s disease development.


1970 ◽  
Vol 117 (2) ◽  
pp. 325-331 ◽  
Author(s):  
H. C. Agrawal ◽  
A. H. Bone ◽  
A. N. Davison

1. Inhibition of the rate of incorporation of [35S]methionine into protein by phenylalanine was more effective in 18-day-old than in 8-day-old or adult rat brain. 2. Among the subcellular fractions incorporation of [35S]methionine into myelin proteins was most inhibited in 18-day-old rat brain. 3. Transport of [35S]methionine and [14C]leucine into the brain acid-soluble pool was significantly decreased in 18-day-old rats by phenylalanine (2mg/g body wt.). The decrease of the two amino acids in the acid-soluble pool equalled the inhibition of their rate of incorporation into the protein. 4. Under identical conditions, entry of [14C]glycine into the brain acid-soluble pool and incorporation into protein and uptake of [14C]acetate into lipid was not affected by phenylalanine. 5. It is proposed that decreased myelin synthesis seen in hyperphenylalaninaemia or phenylketonuria may be due to alteration of the free amino acid pool in the brain during the vulnerable period of brain development. Amyelination may be one of many causes of mental retardation seen in phenylketonuria.


Crustacyanin, the blue carapace pigment of the common lobster Homarus gammarus (L.), has been purified and crystallized. This chromoprotein has a minimum molecular weight of 36 000 based on the content of the carotenoid prosthetic group astaxanthin. The molecular weight in gel filtration measurements is about 650 000, corresponding to some 18 molecules of astaxanthin per molecule of protein. Crustacyanin, on dialysis against water, dissociates into particles of about 35 000 molecular weight, each apparently bearing one molecule of carotenoid. The dissociation is accompanied by a shift in the principal maximum of the absorption spectrum from 633 to 595 nm and is reversed upon addition of salt. Reversible dissociation also occurs in the presence of 3 M urea, 1 M potassium thiocyanate, 10% (v/v) dioxan or 10% (v/v) acetone. When the carotenoid is removed from crustacyanin with acetone, the resul­tant apoprotein has a mean molecular weight of about 20 000. It may be resolved by starch gel electrophoresis into several components of which two predominate. Crustacyanin, indistinguishable from the native material, can be reconstituted from apoprotein and carotenoid. Evidence from the behaviour of crustacyanin and its apoprotein at surfaces indicates that the tertiary and quaternary structures of the native protein are stabilized by the carotenoid. It is suggested that the quaternary structure of crustacyanin is induced by an interaction of the carotenoid molecules of the subunits, which in turn causes a change in configuration of the protein favourable to aggregation. The result is a micelle-like structure with a hydrophobic carotenoid core.


1969 ◽  
Vol 115 (5) ◽  
pp. 1051-1062 ◽  
Author(s):  
N. L. Banik ◽  
A. N. Davison

1. Subcellular fractions and myelin were isolated from developing and adult rat brain. 2. Measurements of chemical composition and enzyme activities indicate the presence of a second myelin-like fraction mainly in the brain of developing rats. 3. This membrane fraction has a different lipid composition from myelin, but resembles myelin in its content of phosphohydrolase and aminopeptidase activity. 4. It is suggested that the second myelin-like fraction may be a submicrosomal contaminant or it may be derived from oligodendroglial plasma membrane during myelinogenesis.


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