Effect of brain serotonin on the arterial pressure and plasma renin in normal and hypertensive rats]

The effects of changes in brain serotonin content after injections of p-chlorophenylalanine (p-CPA), L-5-hydroxytryptophan (L-5HTP) and 5-6-dihydroxytryptamine (5-6DHT) on the mean arterial pressure (MAP), plasma renin activity (PRA) and peripheral levels of atrial natriuretic peptide (ANP) have been studied in normal and hypertensive (2K:1C model) male Wistar rats. The p-CPA (250 mg/kg) and L-5HTP (200 mg/kg) were injected i.p., while 5-6 DHT (15 micrograms/animal in 10 mu/animal vehicle) was injected into lateral brain ventricles. The effects were studied 24 h after the p-CPA injection, 2 h after L-5HTP and 10 or 20 days after 5-6DHT administration. The fall in brain serotonin produced by p-CPA and 5-6DHT did not modify the MAP values in the normal and hypertensive rat model, whereas the increase induced after L-5HTP injection only caused a slight decrease in arterial pressure in normotensive animals. The ARP experimented remarkable rises in the normal and hypertensive rats, these values increasing after L-5HTP and falling after p-CPA and 5-6 DHT injections. Similar changes are detected in the normal group after administration of these substances related to serotoninergic brain activity. The ANP levels rose after renal artery constriction, and they are not affected by the above mentioned substances. Only p-CPA and 5-6DHT reduced a low decrease in the ANP levels 10 days after their administration.(ABSTRACT TRUNCATED AT 250 WORDS)     

Members of the alpha-amylase inhibitors family from wheat endosperm are major allergens associated with baker's asthma

We have identified the major antigens or IgE binding components from wheat flour. Thirty-five sera from patients with baker's asthma were used to analyze the reaction with wheat salt-soluble proteins. We found a 15 kDa SDS-PAGE band which reacted with all sera tested. Purified members of the alpha-amylase inhibitor family, which are the main components of the 15 kDa band, were recognized by specific IgE when tested with a pool of reactive sera. Immunodetection after two-dimensional electrophoretic fractionation of crude inhibitor preparations from wheat endosperms also detected several inhibitor subunits as major low-molecular-weight allergens.     

Biogenesis of mitochondria. Defective assembly of the proteolipid into the mitochondrial adenosine triphosphatase complex in an oli2 mit− mutant of Saccharomyces cerevisiae

A single mutation in the oli2 region of the mitochondrial DNA causes a charge alteration in a mitochondrially translated subunit of the mitochondrial ATPase (subunit 6; apparent M_r 20 000; apparent pI 6.9 and 7.1). This alteration leads to the defective assembly of the proteolipid subunit into the enzyme complex. The mutant, which is able to grow only very slowly by oxidative metabolism at 28°C offers new possibilities for studying the assembly of the membrane sector (F₀) into the mitochondrial ATPase complex and the role of subunit 6 in this process.     

Contribution to the study of cytokinin production by phytopathogenic fungi

The excretion of cytokinins into the cultivating medium, which are produced by the phytopathogenic fungiMonilia sp. andCytospora sp. has been investigated. All the isolates of the fungi used in the experiments (Monilia fructicola, Monilia fructigena, isolate 2 and 4,Monilia laxa isolate 3 andCytospora sp. isolate CPL and C₁) have been found to produce cytokinins. The production is increased during the formation of the fructification organs. Among the isolates investigatedMonilia fructigena isolate 4 andCytospora sp. isolate CPL showed the highest production of cytokinins. After chromatographic separation, cytokinin activity was found at R_F 0.7–0.8 values by the biological test as well as by identification according to UV spectra. Application of purified cytokinins produced by the fungi evoked the formation of “green islands” on isolated barley leaves underin vitro conditions.     

Prefrontal deep projection neurons enable cognitive flexibility via persistent feedback monitoring

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Response to lethal UVA radiation in the Antarctic bacterium Pseudomonas extremaustralis: polyhydroxybutyrate and cold adaptation as protective factors

Extremophiles - Pseudomonas extremaustralis is an Antarctic bacterium with high stress resistance, able to grow under cold conditions. It is capable to produce polyhydroxyalkanoates (PHAs) mainly...     

Rosuvastatin protects isolated hearts against ischemia-reperfusion injury: role of Akt-GSK-3β, metabolic environment,and mitochondrial permeability transition pore

Journal of Physiology and Biochemistry - The cardioprotective activity of rosuvastatin (R) is yet to be known. The objective of this study was to research whether R perfusion before global ischemia...