Sodium channels in presynaptic nerve terminals. Regulation by neurotoxins.

Sodium channels in presynaptic nerve terminals. Regulation by neurotoxins

Regulation of Na+ channels by neurotoxins has been studied in pinched-off nerve endings (synaptosomes) from rat brain. Activation of Na+ channels by the steroid batrachotoxin and by the alkaloid veratridine resulted in an increase in the rate of influx of 22Na into the synaptosomes. In the presence of 145 mM Na+, these agents also depolarized the synaptosomes, as indicated by increased fluoresc...

Localization of Calcium in Presynaptic Nerve Terminals

Ultrastructural techniques and electron probe microanalysis were used to determine whether or not the smooth endoplasmic reticulum (SER) within presynaptic nerve terminals is a Ca-sequestering site . The three-dimensional structure of the SER was determined from serial sections of synaptosomes. The SER consists of flattened cisterns that may branch and are frequently juxtaposed to mitochondria ...

Spider Neurotoxins Targeting Voltage-gated Sodium Channels !

Ion channels in presynaptic nerve terminals and control of transmitter release.

The primary function of the presynaptic nerve terminal is to release transmitter quanta and thus activate the postsynaptic target cell. In almost every step leading to the release of transmitter quanta, there is a substantial involvement of ion channels. In this review, the multitude of ion channels in the presynaptic terminal are surveyed. There are at least 12 different major categories of io...

The Regulation of Cytosolic pH in Isolated Presynaptic Nerve Terminals from Rat Brain

I N T R O D U C T I O N Cytosolic p H (pHi) is a key regu la to r o f many cellular processes (e.g., Roos and Boron, 1981), including the release o f neuro t ransmi t te r s f rom presynaptic nerve * Deceased December 16, 1986. Address reprint requests to Dr. Pierre Drapeau, Neurology Dept., Montreal General Hospital, Montreal, Quebec H3G 1A4, Canada. J. GF~. PHYSIOL. 9 The Rockefeller Universi...