Search results for "Brain tissue"

Improved method for cannula fixation for long-term intracerebral brain infusion

2017

Abstract Background Implanted osmotic minipumps are commonly used for long-term, brain-targeted delivery of a wide range of experimental agents by being connected to a catheter and a cannula. During the stereotactical surgery procedure, the cannula has to be placed correctly in the x-y directions and also with respect to the injection point in the z-direction (deepness). However, the flat fixation base of available cannula holders doesn’t allow an easy, secure fixation onto the curve-shaped skull. New method We have developed a modified method for a better fixation of the cannula holder by using an easy-to-produce, skull-shaped silicone spacer as fixation adapter. Results We describe the ap…

Local H2-Clearance and PO2-Measurements in Microareas of the Brain Tissue in Rats

1969

Lubbers [5], as well as others, measured the oxygen partial pressure of the exposed cerebral cortex by means of small platinum microelectrodes. They registered low pO2 values between 1 and 3 mmHg in certain areas of the cortex, despite the fact that the EEG was of normal pattern. In order to decide whether these low pO2 values are a result of low rCBF, or high local oxygen consumption of brain tissue, we developed a new method. Using the same platinum needle, we measured both local pO2 values and H2-clearance curves in microareas of the brain tissue. Cater and Silver [2], Lubbers [4, 5], and others used glass-insulated platinum microelectrodes to measure local pO2. Further, Aukland, Bower a…

MDMA Administration and Heat Shock Proteins Response: Foreseeing a Molecular Link

2010

Molecular and cellular mechanisms of MDMA-induced toxicity have been extensively studied in a number of experimental models. Nevertheless, only few studies investigated the involvement of HSPs ("molecular chaperones") in MDMA organs toxicity. In the present minireview we highlight this subject analysing the results of these studies conducted especially on brain tissue. Despite of it seems obvious that HSPs overexpression is a protective reaction against MDMA treatment, the molecular mechanisms for exerting their action are far to be undiscovered. At the same time, we need of comprehensive studies concerning the whole range of Hsps/chaperones expressions in all organs after acute and chronic…

Investigating the use of primary adult subventricular zone neural precursor cells for neuronal replacement therapies

2002

With the relatively recent discovery that neurogenesis persists throughout life in restricted regions of the adult mammalian brain, including those of human beings, there has been great interest in the use of adult-derived neural stem cells for neuronal replacement. There are many great hurdles that must be overcome in order for such replacement strategies to succeed. In this review, we outline some of these hurdles and discuss recent experiments that investigate the potential of using neural precursor cells found in the subventricular zone of the adult brain for brain repair.

New neurons follow the flow of cerebrospinal fluid in the adult brain

2006

Autores: Sawamoto, K. et al. .- PMID:16410488

The Erythrocytic Hypothesis of Brain Energy Crisis in Sporadic Alzheimer Disease: Possible Consequences and Supporting Evidence

2020

Alzheimer’s disease (AD) is a fatal form of dementia of unknown etiology. Although amyloid plaque accumulation in the brain has been the subject of intensive research in disease pathogenesis and anti-amyloid drug development; the continued failures of the clinical trials suggest that amyloids are not a key cause of AD and new approaches to AD investigation and treatment are needed. We propose a new hypothesis of AD development based on metabolic abnormalities in circulating red blood cells (RBCs) that slow down oxygen release from RBCs into brain tissue which in turn leads to hypoxia-induced brain energy crisis; loss of neurons; and progressive atrophy preceding cognitive dysfunction. This …

Ethical challenges in cell-based interventions for neurological conditions: some lessons to be learnt from clinical transplantation trials in patient…

2009

The Role of Monoamines in the Development of Cold-Induced Edema

1976

Our results show that even the experimentally induced high concentrations of exogenous 5-HT in the brain tissue during the early phase of edema formation are not able to increase the amount of fluid accumulation in the normal and injured brain tissue. The changes of the endogenous 5-HT levels in the blood and the brain tissue result in similar hemispheric water and RISA differences between the injured and uninjured half of the brain. Moreover, 5-HT concentrations elevated by 100% failed to produce detectable edema in the normal brain tissue of the rat.

Serotonergic modulation of hippocampal acetylcholine release after long-term neuronal grafting

2000

Adult female rats sustained aspirative fimbria-fornix lesions and, 2 weeks later, received intrahippocampal grafts of fetal septal or mixed septal-raphe cell suspensions. Twenty-four months later, the extracellular concentration of hippocampal acetylcholine (ACh) was determined by microdialysis. Basal ACh levels (5-65 fmol/5 microl sham-operated rats) were strongly reduced after lesioning (3-7 fmol/5 microl). In septally transplanted and septal-raphe co-transplanted rats, hippocampal ACh concentrations were restored to near-normal levels (15-25 fmol/5 microl), indicating long-term functional survival of hippocampal transplants. After administration of citalopram (100 microM by infusion) and…

Modulation of hippocampal acetylcholine release after fimbria-fornix lesions and septal transplantation in rats

1997

Abstract Female Long–Evans rats sustained electrolytic lesions of the fimbria and the dorsal fornix causing a partial lesion of the septohippocampal pathway. Two weeks later, the rats received intra-hippocampal grafts of fetal septal cell suspensions. Nine to twelve months later, the release of acetylcholine (ACh) in the hippocampus of sham-operated, lesion-only and grafted rats was measured by microdialysis. The extent of cholinergic (re)innervation was determined by acetylcholinesterase (AChE) staining and densitometry. In both lesion-only and grafted rats, the ratio of ACh release to AChE staining intensity was increased as compared to sham-operated rats, indicating a loss of endogenous …