Brain tissue is extremely heterogeneous—being comprised of neurons (which are often myelinated) and a number of glial cell types—and, therefore, requires some purification in order to study neuronal and glial functioning in isolation at the molecular level. The introduction of the ult ...
It is generally thought that up to 90% of all synapses in the mammalian brain use amino acids as neurotransmitters (1). Neurotransmitter amino acids may either be those that are also used directly as protein constituents (such as glutamate) or modified amino acids, such as γ-amino butyric acid (GAB ...
Immunocytochemistry (ICC) of small, water-soluble molecules requires some special precautions compared to ICC of large protein molecules. In general, protein antigens are relatively insensitive to the type of fixative used. Apparently, the epitopes are not altered in a decisive way ...
Exocytotic fusion of secretory vesicles with the plasma membrane occurs in cells in either a constitutive or regulated fashion (Burgess and Kelly, 1987). Constitutive exocytosis is the mechanism by which membrane components and certain soluble proteins are released. In the regulated ...
Rod and cone photoreceptors transduce the absorption of a photon of light into an electrical response. Within the last decade, our understanding of photoreceptors has increased enormously, and this growth in understanding has resulted in large part from the application of new electrop ...
Invertebrate phototransduction is a central subject in neuroscience that includes several key topics with implications to a wide variety of cells and tissues. The phototransduction cascade begins with isomerization of the retinoid chromophore by photons that activate the phot ...
Inositol 1,4,5-trisphosphate (Ins(1,4,5)P 3) was first shown to stimulate mobilization of intracellular Ca2+ from permeabilized pancreatic acinar cells (Streb et al., 1983) and has since become recognized as an intracellular messenger formed after receptor activation and then res ...
There is now compelling evidence that stimulation of inosito1 phospholipid metabolism via phosphoinositidase C (MC) is the signal transduction pathway for a wide variety of receptors in the mammalian nervous system. A by no means comprehensive list is shown in Table 1. Receptors are thoug ...
Most neurotransmitters, hormones, and growth factors that cause alterations in the rate of synthesis of intracellular messengers interact with cell surface receptors that are members of a family of single polypeptide proteins. Secondary and tertiary structure predictions for s ...
Changes in cytosolic free calcium ion concentration (i) accompany many cellular transitions and stimulation of cell surface receptors. Both release of Ca2+ from internal stores and Ca2+ entry through plasma membrane ion channels can contribute to cellular Ca2+ transients. In the past, d ...
Protein kinase C is a key element in signal transduction, cell regulation, and tumor promotion, influencing cellular responses to many stimuli at a variety of levels, including receptors, transduction systems, ion channels, and membrane pumps. Although it was once thought of as a single enti ...
This chapter will describe and assess the technology by which optical indicators are used to produce images that show the distribution of a measured quantity, such as free ion concentration or electric potential, within individual cells. Common ions whose free concentrations, or activi ...
Signaling pathways that convert extracellular stimuli into intracellular responses regulate many diverse physiological and biochemical processes, and share many characteristics. An external signal binds to a cell surface receptor and stimulates a transducer to activate an ...
Cyclic nucleotides were discovered about 30 years ago, becoming the prototype intracellular messengers (Robison et al., 1971). Intracellular messenger signaling systems may be split into the following divisions:
The development of caged intracellular messenger compounds offers an elegant new approach to quantitative, time-resolved studies of intracellular signaling pathways. Several reviews of caged compounds have recently appeared (Kaplan and Somlyo, 1989; McCray and Trentham, 19 ...
In contrast to unit action potentials recorded from discrete neurons, field potentials, as the name implies, are not restricted to the spatial domain of a neuron or of the brain. As a result of the volume-conducting properties of the brain, field potentials reflect activity of a population of neuro ...
After the current section, the history (1.2.) of evoked potentials (EP—for abbreviations, see the end of this chapter) is briefly presented, followed by a discussion of how EPs can be broken down into components (1.3.). General methodology (2.) is then presented, covering recording techniques (2 ...
In the past dozen years, newly developed chronic recording techniques have made possible the direct study of peripheral nerve and spinal cord function in conscious, freely moving animals. Two complementary approaches were introduced in the mid-1970s: floating microelectrodes to r ...
In addition to desensitization and downregulation of receptors at the cell membrane, the number of receptors expressed is modulated by regulation of steady-state levels of mRNA and the rate of gene transcription (see refs. 1 and 2 for reviews). Regulation of receptor mRNA and gene transcript ...
A frequently observed adaptive response to chronic agonist occupancy of cell surface receptors is a process in which receptors become internalized or sequestered into a cell compartment to which hydrophilic ligands have only a limited access (1–3). Although receptor sequestration ...