Brain Tissue In Vivo

Initial studies of brain delivery based on the chimeric peptide strategy used the absorptive-mediated uptake of cationized albumin which was chemically coupled to the opioid peptide P-endorphin [80] or its metabohcaUy stabilized analogue [D-Ala ]P-endorphin. Tracer experiments in which the chimeric peptide was labelled in the endorphin moiety provided evidence of internalization by isolated brain capillaries and transport into brain tissue in vivo [81]. 

Drejer J, Benveniste H, Diemer NH, Schousboe A. 1985. Cellular origin of ischemia-induced glutamate release from brain tissue in vivo and in vitro. J Neurochem 45 145-151. 

L. Lilge, M. Portnoy, B.C. Wilson (1999). PDT-induced apoptosis in brain tissue in vivo. In Th.J. Dougherty (Ed.), Optical Methods for Tumor Treatment and Detection Mechanisms and Techniques in Photodynamic Therapy VIII (SPIE-Proc. Vol. 3592, pp. 28-36). 

Calibration of voltammetric electrodes When electrodes are implanted into brain tissue, in vivo responses of the working electrodes to catechols are, more or less, affected by the environment or by drug treatments. The main effects are the change in sensitivity, in the position of oxidation peaks, and resolution between adjacent peaks. Therefore, it is generally accepted to characterize the electrodes by testing in vitro response before and after the in vivo measurements. 

The applicability of autofluorescence and diffuse-reflectance spectroscopy for intraoperative detection of brain tumors was investigated in a clinical trail (Lin et al, 2001). The result suggested that brain tumors and infiltrating tumor regions can be effectively separated from normal brain tissues in vivo using a combination of diese techniques. 

Miller, K., K. Chinzei, G. Orssengo, and R Bednarz. 2000b. Mechanical properties of brain tissue in-vivo Experiment and computer simulation. Journal of Biomechanics 33(11) 1369-76. 

Miller K, Chinzei K, Orssengo G et al. (2000) Mechanical properties of brain tissue in-vivo experiment and computer simulation. J Biomech 33 1369-1376... 

Walsh EK, Schettini A (1976) Elastic behavior of brain tissue in vivo. Am J Physiol 230 1058-1062... 

The aromatization of testosterone to form estradiol, and of androstenedione to form estrone (Fig. 52-4), has been described in brain tissue in vitro and in vivo [1, 9]. Aromatization is higher in hypothalamus and limbic... 

Prokai L, Kim HS, Zharikova A, Roboz J, Ma L, et al. 1998. Electrospray ionization mass spectrometric and liquid chromatographic-mass spectrometric studies on the metabolism of synthetic dynorphin A peptides in brain tissue in vitro and in vivo. J Chromatogr A 800 59. 

Unfortunately, it is not always possible to measure oxygen consumption for some cells or tissues in vivo for example, for cells that circulate in blood or in the lymph (e.g. red blood cells, immune cells), for different cells in one organ (e.g. macrophages in liver, glial cells in the brain,... 

Chattopadhyay, S., Bhaumik, S., Nag Chaudhury, A. and Das Gupta, S. (2002) Arsenic induced changes in growth development and apoptosis in neonatal and adult brain cells in vivo and in tissue culture. Toxicology Letters, 128(1-3), 73-84. 

A molecule such as cyclic AMP, cyclic GMP or phosphatidylinositol that regulates intracellular processes in response to an extracellular signal. Uncontrolled or paroxysmal brain activity that is usually expressed through the motor system. Antidepressants such as fluoxetine and fluvoxamine that show specificity in inhibiting the uptake of 5-hydroxytryptamine into platelets or brain tissue in vitro and in vivo. 

Strauss and Dager [42] also measured the relative contribution of unbound versus bound fluoxetine and metabolites to the 19F MR visible signal in vivo in the human brain by applying magnetization transfer methods to acquire 19F MR spectra. Signals from the bound form of fluoxetine/norfluoxetine were found to be approximately 14.2% of those detected from the unbound form [42], A similar binding or interaction between fleroxacin in plasma in vitro and in tissue in vivo was found [23]. Understanding the nature and characteristics of the in vivo spectrum was a prerequisite for quantitation of the resultant fleroxacin 19F spectra. 

Another example of the use of small electrodes is Jahnke et al. (2013), who used a flexible microelectrode array to separate between brain and tumor tissue in vivo. 

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