The Role of Extracellular Potassium and Hydrogen Activities in the Brain Cortex for Regulation of Cerebral Microcirculation in the Cat During Generalized Seizures and Specific Sensory Stimulation

Author(s):  
E. Leniger-Follert ◽  
C. Danz
1998 ◽  
Vol 44 (1) ◽  
pp. 40-42
Author(s):  
I. P. Grigoriev

The author hypothesizes a probable causative role of alteration of ascorbic acid concentration in the brain in the development of mental disease in diabetics. In order to verify this hypothesis, ascorbic acid was measured in the brain cortex of rats 21 days after induction of streptozotocin diabetes or 1 h after intraperitoneal injection of glucose in a dose of 5 g/kg. Ascorbic acid level was increased both in diabetes (456+26 yg/g tissue versus 415+37 \vg/g in the control, p<0.01) and in acute hyperglycemia (475+54 \tg/g versus 406+65 \xg/g in the control, p<0.001). This confirmed that changed concentration of ascorbic acid in the brain can promote the development of a mental disease in diabetics. In the liver the concentration of ascorbic acid was decreased in streptozotocin diabetes (by 17%), p<0.001) and increased in acute hypoglycemia (by 24%, p<0.01). The findings permit us to hypothesize that hypoglycemia inhibits the production of ascorbic acid from the liver to the blood in rats and impedes the transport of ascorbic acid through the gut wall into the blood in humans.


Open Medicine ◽  
2013 ◽  
Vol 8 (4) ◽  
pp. 517-522
Author(s):  
Leonid Godlevsky ◽  
Semen Tsevelev ◽  
Vyacheslav Polyasny ◽  
Igor Samchenko ◽  
Tatyana Muratova

AbstractThe work was dedicated to investigation of dynamics of epileptic activity in conditions of extremely high frequency electromagnetic waves (EHF) radiation (7,1 mm, 0,1 mW/cm2) upon focal epileptic activity. Epileptic activity was penicillin-induced (10,000 IU/ml) in the frontal region of the brain cortex in myorelaxed and artificially ventilated rats under acute experimental condition. Thermal effects were absent as far as absorbed dosage of energy did not exceed 0,1 J/ animal. It was established that preliminarily performed hypogeomagnetic period (3,0 h) with the inductivity of geomagnetic field at 5×10−8 Tesla caused the intensification of antiepileptic effects of EHF (15,0 min of exposure). It was pronounced in the form of decrease of foci intensity and significant reduction of lifespan of foci — up to 115,3±13,4 minutes, which was both significant when compared with separate effects of hypogeomagnetic influence (187,3±12,5 min) and EHF (15,0 minutes of exposure) effect (164,2±12,5 minutes) (P<0,05). Besides, EHF (15,0 min) which was made after 3,0 h exposure to hypogeomagnetic influence suppressed generalized seizures in amygdalarly kindled rats.


2021 ◽  
Vol 22 (21) ◽  
pp. 11465
Author(s):  
Ewa Szczepanska-Sadowska ◽  
Agnieszka Wsol ◽  
Agnieszka Cudnoch-Jedrzejewska ◽  
Tymoteusz Żera

The neurons secreting oxytocin (OXY) and vasopressin (AVP) are located mainly in the supraoptic, paraventricular, and suprachiasmatic nucleus of the brain. Oxytocinergic and vasopressinergic projections reach several regions of the brain and the spinal cord. Both peptides are released from axons, soma, and dendrites and modulate the excitability of other neuroregulatory pathways. The synthesis and action of OXY and AVP in the peripheral organs (eye, heart, gastrointestinal system) is being investigated. The secretion of OXY and AVP is influenced by changes in body fluid osmolality, blood volume, blood pressure, hypoxia, and stress. Vasopressin interacts with three subtypes of receptors: V1aR, V1bR, and V2R whereas oxytocin activates its own OXTR and V1aR receptors. AVP and OXY receptors are present in several regions of the brain (cortex, hypothalamus, pons, medulla, and cerebellum) and in the peripheral organs (heart, lungs, carotid bodies, kidneys, adrenal glands, pancreas, gastrointestinal tract, ovaries, uterus, thymus). Hypertension, myocardial infarction, and coexisting factors, such as pain and stress, have a significant impact on the secretion of oxytocin and vasopressin and on the expression of their receptors. The inappropriate regulation of oxytocin and vasopressin secretion during ischemia, hypoxia/hypercapnia, inflammation, pain, and stress may play a significant role in the pathogenesis of cardiovascular diseases.


Author(s):  
J.E. Johnson

Although neuroaxonal dystrophy (NAD) has been examined by light and electron microscopy for years, the nature of the components in the dystrophic axons is not well understood. The present report examines nucleus gracilis and cuneatus (the dorsal column nuclei) in the brain stem of aging mice.Mice (C57BL/6J) were sacrificed by aldehyde perfusion at ages ranging from 3 months to 23 months. Several brain areas and parts of other organs were processed for electron microscopy.At 3 months of age, very little evidence of NAD can be discerned by light microscopy. At the EM level, a few axons are found to contain dystrophic material. By 23 months of age, the entire nucleus gracilis is filled with dystrophic axons. Much less NAD is seen in nucleus cuneatus by comparison. The most recurrent pattern of NAD is an enlarged profile, in the center of which is a mass of reticulated material (reticulated portion; or RP).


Author(s):  
Enrico D.F. Motti ◽  
Hans-Georg Imhof ◽  
Gazi M. Yasargil

Physiologists have devoted most attention in the cerebrovascular tree to the arterial side of the circulation which has been subdivided in three levels: 1) major brain arteries which keep microcirculation constant despite changes in perfusion pressure; 2) pial arteries supposed to be effectors regulating microcirculation; 3) intracerebral arteries supposed to be deprived of active cerebral blood flow regulating devices.The morphological search for microvascular effectors in the cerebrovascular bed has been elusive. The opaque substance of the brain confines in vivo investigation to the superficial pial arteries. Most morphologists had to limit their observation to the random occurrence of a favorable site in the practically two-dimensional thickness of diaphanized histological sections. It is then not surprising most investigators of the cerebral microcirculation refer to an homogeneous network of microvessels interposed between arterioles and venules.We have taken advantage of the excellent depth of focus afforded by the scanning electron microscope (SEM) to investigate corrosion casts obtained injecting a range of experimental animals with a modified Batson's acrylic mixture.


1969 ◽  
Vol 21 (02) ◽  
pp. 294-303 ◽  
Author(s):  
H Mihara ◽  
T Fujii ◽  
S Okamoto

SummaryBlood was injected into the brains of dogs to produce artificial haematomas, and paraffin injected to produce intracerebral paraffin masses. Cerebrospinal fluid (CSF) and peripheral blood samples were withdrawn at regular intervals and their fibrinolytic activities estimated by the fibrin plate method. Trans-form aminomethylcyclohexane-carboxylic acid (t-AMCHA) was administered to some individuals. Genera] relationships were found between changes in CSF fibrinolytic activity, area of tissue damage and survival time. t-AMCHA was clearly beneficial to those animals given a programme of administration. Tissue activator was extracted from the brain tissue after death or sacrifice for haematoma examination. The possible role of tissue activator in relation to haematoma development, and clinical implications of the results, are discussed.


2009 ◽  
Vol 150 (46) ◽  
pp. 2101-2109 ◽  
Author(s):  
Péter Csécsei ◽  
Anita Trauninger ◽  
Sámuel Komoly ◽  
Zsolt Illés

The identification of autoantibodies generated against the brain isoform water channel aquaporin4 in the sera of patients, changed the current diagnostic guidelines and concept of neuromyelitis optica (NMO). In a number of cases, clinical manifestation is spatially limited to myelitis or relapsing optic neuritis creating a diverse. NMO spectrum. Since prevention of relapses provides the only possibility to reduce permanent disability, early diagnosis and treatment is mandatory. In the present study, we discuss the potential role of neuroimaging and laboratory tests in differentiating the NMO spectrum from other diseases, as well as the diagnostic procedures and therapeutic options. We also present clinical cases, to provide examples of different clinical settings, diagnostic procedures and therapeutic decisions.


Sign in / Sign up

Export Citation Format

Share Document