Hormuzdi Physiology Flashcards
Which ions have an excitatory effect (depolarizing) on a cell when they influx?
Na+
Ca+
Which ion has an inhibitory effect (hyperpolarizing) on a cell with influx?
Cl-
Which ion has an inhibitory effect (hyperpolarizing) on a cell with efflux?
K+
What would be the effect of an Na channel antagonist on neurotransmission? Give an example of a drug that works like this
Closes Na channel, stops Na influx, hyperpolarizing (inhibitory) effect, cell relaxes
e.g. lidocaine in anaesthesia
Influx of which ion, in response to depolarization, causes exocytosis of neurotransmitter at the synaptic cleft?
Ca
What are the 2 main types of receptor neurotransmitter can act on in the postsynaptic cell?
Ionotropic receptor (direct) Metabotropic receptor (indirect)
What is the structural/mechanical difference between ionotropic and metabotropic receptors?
Ionotropic = channel molecule Metabotropic = signalling molecule
The action of a metabotropic receptor is sufficient to illicit an action potential. True/False?
False
Which receptor does ACh act on in autonomic ganglia - ionotropic or metabotropic?
Both!
ACh acting on ionotropic receptors illicits a fast/slow epsp
ACh acting on ionotropic receptors illicits a fast epsp
ACh acting on metabotropic receptors illicits a fast/slow epsp
ACh acting on metabotropic receptors illicits a slow epsp
Out of ACh, GABA, glycine and glutamine, which are excitatory and which are inhibitory neurotransmitters?
Excitatory: ACh, glutamine
Inhibitory: GABA, glycine
GABAa is the ionotropic/metabotropic receptor and GABAb is the ionotropic/metabotropic receptor
GABAa is the ionotropic receptor and GABAb is the metabotropic receptor
How do benzodiazepines work in terms of GABA inhibition?
Positively modulate GABAa receptor to enhance GABA neuro-inhibition
What is the normal frequency range for sound that humans can hear?
20-20,000 Hz