BCM and Membrane Potential: Alternative Ways to Timing Dependent Plasticity

2009 ◽  
pp. 137-144 ◽  
Author(s):  
Johannes Partzsch ◽  
Christian Mayr ◽  
Rene Schüffny
Keyword(s):  
Membrane Potential ◽  
Dependent Plasticity ◽  
Potential Alternative

Measurement of spontaneous neuronal membrane activity by time lapse confocal microscopy

1995 ◽  
Vol 53 ◽  
pp. 972-973
Author(s):  
R H. Selinfreund ◽  
A. H. Cornell-Bell
Keyword(s):  
Membrane Potential ◽  
Confocal Microscopy ◽  
Patch Clamp ◽  
Electrical Activity ◽  
Time Lapse ◽  
Neuronal Firing ◽  
Neuronal Membrane ◽  
Pituitary Cells ◽  
Patch Clamp Recording ◽  
Spontaneous Electrical Activity

Cellular electrophysiological properties are normally monitored by standard patch clamp techniques . The combination of membrane potential dyes with time-lapse laser confocal microscopy provides a more direct, least destructive rapid method for monitoring changes in neuronal electrical activity. Using membrane potential dyes we found that spontaneous action potential firing can be detected using time-lapse confocal microscopy. Initially, patch clamp recording techniques were used to verify spontaneous electrical activity in GH4\C1 pituitary cells. It was found that serum depleted cells had reduced spontaneous electrical activity. Brief exposure to the serum derived growth factor, IGF-1, reconstituted electrical activity. We have examined the possibility of developing a rapid fluorescent assay to measure neuronal activity using membrane potential dyes. This neuronal regeneration assay has been adapted to run on a confocal microscope. Quantitative fluorescence is then used to measure a compounds ability to regenerate neuronal firing.The membrane potential dye di-8-ANEPPS was selected for these experiments. Di-8- ANEPPS is internalized slowly, has a high signal to noise ratio (40:1), has a linear fluorescent response to change in voltage.

Fluorescent potentiometric dyes for membrane-potential imaging

1994 ◽  
Vol 52 ◽  
pp. 166-167
Author(s):  
Leslie M. Loew
Keyword(s):  
Membrane Potential ◽  
Single Cells ◽  
Quantitative Imaging ◽  
Optical Recording ◽  
Biological Processes ◽  
Major Focus ◽  
The Past ◽  
Excitable Systems ◽  
Major Application ◽  
The Impact

A major application of potentiometric dyes has been the multisite optical recording of electrical activity in excitable systems. After being championed by L.B. Cohen and his colleagues for the past 20 years, the impact of this technology is rapidly being felt and is spreading to an increasing number of neuroscience laboratories. A second class of experiments involves using dyes to image membrane potential distributions in single cells by digital imaging microscopy - a major focus of this lab. These studies usually do not require the temporal resolution of multisite optical recording, being primarily focussed on slow cell biological processes, and therefore can achieve much higher spatial resolution. We have developed 2 methods for quantitative imaging of membrane potential. One method uses dual wavelength imaging of membrane-staining dyes and the other uses quantitative 3D imaging of a fluorescent lipophilic cation; the dyes used in each case were synthesized for this purpose in this laboratory.

Rehabilitation of Attention

2003 ◽  
Vol 14 (3) ◽  
pp. 165-170 ◽  
Author(s):  
Ian H. Robertson
Keyword(s):  
Brain Damage ◽  
Dependent Plasticity ◽  
Attention Systems ◽  
The Brain

Abstract: In this paper, evidence is reviewed for separable attention systems in the brain, and it is argued a) that attention may have a privileged role in mediating experience dependent plasticity in the brain and b) that at least some types of attention may be capable of rehabilitation following brain damage.

Prevalence and Induction of Circulating Antibodies against Recombinant Staphylokinase

1994 ◽  
Vol 71 (01) ◽  
pp. 129-133 ◽  
Author(s):  
P J Declerck ◽  
S Vanderschueren ◽  
J Billiet ◽  
H Moreau ◽  
D Collen
Keyword(s):  
Intravenous Administration ◽  
Human Subjects ◽  
Microtiter Plates ◽  
Staphylococcus Aureus Bacteremia ◽  
Alternative Agent ◽  
Antibody Titers ◽  
Potential Alternative ◽  
Circulating Antibodies ◽  
Low Levels ◽  
Antibody Levels

SummaryStreptokinase (SK) is a routinely used thrombolytic agent but it is immunogenic and allergenic; staphylokinase (STA) is a potential alternative agent which is under early clinical evaluation. The comparative prevalence of antibodies against recombinant STA (STAR) and against SK was studied in healthy subjects and their induction with intravenous administration in small groups of patients.Enzyme-linked immunosorbent assays, using microtiter plates coated with STAR or SK and calibration with affinospecific human antibodies, revealed 2.1 to 65 μg/ml (median 11 μg/ml) anti-STAR antibodies and 0.9 to 370 μg/ml (median 18 μg/ml) anti-SK antibodies (p <0.001 vs anti-STAR antibodies) in plasma from 100 blood donors, with corresponding values of 0.6 to 100 μg/ml (median 7.1 μg/ml) and 0.4 to 120 μg/ml (median 7.3 μg/ml), respectively, in 104 patients with angina pectoris. Three out of 17 patients with Staphylococcus aureus bacteremia had significantly increased anti-STAR antibody levels (150, 75 and 75 μg/ml), and STAR neutralizing activities (2.2, 3.6 and 4.1 μg STAR neutralized per ml plasma, respectively). In 6 patients with acute myocardial infarction, given 10 mg STAR intravenously over 30 min, median anti-STAR antibody levels were 3.5 μg/ml at baseline, 2.9 μg/ml at 6 to 8 days and 1.2 μg/ml at 2 to 9 weeks, with median corresponding titers of STAR neutralizing activity at 2 to 9 weeks of 42 μg/ml plasma. Conversely, in 5 patients treated with 1,500,000 units SK over 60 min, median anti-SK antibodies increased from 2.9 μg/ml at baseline to 360 μg/ml at 5 to 10 days, with corresponding median SK neutralizing activities of 13 μg/ml. Antibodies against STAR did not cross-react with SK and vice versa.Plasma from human subjects contains low levels of circulating antibodies against recombinant staphylokinase, and intravenous administration of this compound boosts antibody titers. These antibodies do however not cross-react with streptokinase, whereby the use of these two immunogenic thrombolytic agents would not be mutually exclusive.

Sign in / Sign up

Export Citation Format

Share Document