ISSN:
1573-6830
Keywords:
angiotensin
;
saralasin
;
hippocampal slice
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Summary 1. The mechanism of action of angiotensins was studied on CA 1 pyramidal cells in hippocampal slices of the rat. Extracellular field potentials, single-cell action potentials, and intracellular excitatory and inhibitory postsynaptic potentials (epsps and ipsps) were recorded. 2. Angiotensin II and Des-Asp1-angiotensin II added to the perfusion fluid caused a dose-dependent increase in extracellularly recorded epsps and synaptically evoked population spikes. Either the neurons were depolarized by angiotensins and their firing frequency of action potentials increased or the membrane potential was unaffected. 3. Local application of angiotensins caused a depolarization associated with a conductance increase which was resistant to synaptic isolation. 4. Evoked and spontaneous inhibitory postsynaptic potentials were reduced by angiotensins, but the effects ofγ-aminobutyric acid (GABA) on soma and dendrites were unchanged. 5. All angiotensin effects were blocked by the specific antagonist Sar1, Ala8-angiotensin II (saralasin). 6. It is concluded that angiotensins excite CA 1 pyramidal cells by a direct and a disinhibitory mechanism.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00735064
