ausblenden:
Schlagwörter:
Animals
Brain-Derived Neurotrophic Factor/pharmacokinetics/*pharmacology
Hippocampus/*drug effects/metabolism/physiology
Immunohistochemistry
In Vitro Techniques
Male
Microscopy, Confocal
Nerve Growth Factors/*metabolism
Neuronal Plasticity/*drug effects/physiology
Rats
Rats, Sprague-Dawley
Receptor Protein-Tyrosine Kinases/*physiology
Receptor, Ciliary Neurotrophic Factor
Receptors, Nerve Growth Factor/*physiology
Synapses/*drug effects/physiology
Zusammenfassung:
The neurotrophins are a class of signaling molecules known for their growth and survival-promoting activities during neuronal development. Recent studies suggest that the neurotrophins, including brain-derived neurotrophic factor (BDNF), can also dramatically influence synaptic transmission in the adult hippocampus. The experiments described in this paper indicate that ability of BDNF to potentiate synaptic transmission in the hippocampus relies on functional Trk B receptors. Moreover, the rate at which BDNF is applied to hippocampal synapses is also a potent determinant of whether synaptic potentiation will result. Hippocampal slices perfused with BDNF at a very slow flow rate (e.g., < or = 25 ml/hr) did not show synaptic potentiation. Increasing the rate of BDNF application resulted in synaptic potentiation in which the magnitude and onset kinetics of the potentiation were determined by the rate of BDNF delivery. Immunocytochemical analysis of BDNF detected with confocal microscopy confirmed these electrophysiological observations, indicating that the penetration of BDNF into hippocampal slices is influenced dramatically by the perfusion rate.
