The selective disruption of certain cell types--notably neurons--in diseases involving mitochondrial dysfunction is thought to reflect the high-energy requirements of these cells, but few details are known. Recent studies have provided clues to the cellular basis of this mitochondrial requirement. Mitochondria are regionally organized within some nerve cells, with higher accumulations in the so...

Neuropeptide Y (NPY) is a recently discovered, amidated 36 amino acid residue neuropeptide present in many but not all sympathetic noradrenergic neurons. In the guinea-pig eye, NPY immunoreactive fibers were found to have the same distribution as noradrenergic fibers except that there were fewer at the iris dilator, in the cornea, and in the chamber angle. In the anterior uvea, the NPY immunore...

The goal of this study was to determine which neural elements are excited by microstimulation of the central nervous system. A cable model of a neuron including an axon, initial segment, axon hillock, soma, and simplified dendritic tree was used to study excitation with an extracellular point source electrode. The model reproduced a wide range of experimentally documented extracellular excitati...

Abstract The aims of the study were: (i) to examine how well hillock forests are distinguishable from comparable site types, (ii) ascertain forest indicator species, (iii) elucidate forests’ community (iv) assess practical requirement for differentiation as a self-sufficient typological unit forestry. data included altogether 160 descriptions communities and 42 relevés other type stands compari...

The spatial distribution of transient K current, IA, was studied using a combination of patch-clamp and whole-cell voltage-clamp techniques. The average IA current density in somatic patches is 0.64 times the current density in the entire axotomized cell body, a finding which suggests that the axon hillock or initial segment of the axon has a higher concentration of IA channels than much of som...

A long-standing hypothesis is that action potentials initiate first in the axon hillock/initial segment (AH-IS) region because of a locally high density of Na+ channels. We tested this idea in subicular pyramidal neurons by using patch-clamp recordings in hippocampal slices. Simultaneous recordings from the soma and IS confirmed that orthodromic action potentials initiated in the axon and then ...