Regulation of Voltage-Sensitive Calcium Channels in Brain by Micromolar Affinity Benzodiazepine Receptors
Ca2+ is an important mediator of molecular events in the functioning nerve terminal (1, 2). An increase in cytoplasmic Ca2+ has been shown to regulate a variety of neuronal cell functions, including neurotransmitter release, stimulation of protein phosphorylation, and synaptic morphological changes (3). It is well-established that these events are directly dependent on the entry of extracellular Ca2+ into the presynaptic nerve terminal through specific voltage-gated Ca2+ channels (4,6). The central role of Ca2+ channels in stimulus-secretion coupling mechanisms has led to the extensive investigation of Ca2+ channel function in a wide variety of intact and broken cell preparations (7). Despite extensive electrophysiological characterization of Ca2+ channels in brain, the molecular nature and pharmacological characteristics of this major neuronal Ca2+ channel remain largely unclear.
KeywordsNeurotransmitter Release Presynaptic Nerve Terminal Neuronal Cell Function Intact Synaptosome Break Cell Preparation
Unable to display preview. Download preview PDF.
- 1.Rubin RP: The role of calcium in the release of neurotransmitter substances and hormones. Pharmacology Review 22: 389–428, 1972.Google Scholar
- 2.Rasmussen H, Goodman DBP: Relationships between calcium and cyclic nucleotides in cell activation. Physiology Reviews 57: 421–509, 1977.Google Scholar
- 4.Katz B, Miledi R: Spontaneous and evoked activity of motor nerve endings in calcium Ringer. J Physiol 203: 689–706, 1970.Google Scholar
- 11.Triggle D.J., Janis RA: Nitrendipine: Binding sites and mechanisms of action. In: A Scriabine, S Vanov, and K Deck (eds) Nitrendipine. Urban and Schwarzenberg, Baltimore-Munich, 1984, pp. 33–52.Google Scholar
- 14.Nachshen DA, Blanstein MP: The effects of some organic calcium antagonists on calcium influx in presynaptic nerve terminals. Mol Pharm 16: 579–586, 1979.Google Scholar
- 15.Freedman SB, Miller RJ: Effects of nitrendipine on voltage sensitive calcium channels in brain and neuronal cultured cells. In: A Scriabine, S Vanov, and K Deck (eds) Nitrendipine. Urban and Schwarzenberg, Baltimore-Munich, 1984, pp 79–90.Google Scholar
- 16.Van der Kloot, Kita H: The effects of “calcium-antagonist” verapamil on muscle action potentials in the frog and crayfish and on neuromuscular transmission in the crayfish. Comp Biochem Physiol 50C: 121–125, 1975.Google Scholar
- 22.Ferrendelli JA, Daniels-McQueen S: Comparative actions of phenytoin and other anticonvulsant drugs on potassium-and veratridine-stimulated calcium uptake in synaptosomes. J Pharma exp Ther 220: 29–34, 1982.Google Scholar
- 24.Meyer EM, Cooper JR: Cobalt ions dissociate between calcium uptake through voltage-dependent sodium and calcium channels in synaptosomes. Brain Res 265: 173–176, 1983.Google Scholar