TY  - JOUR
AU  - Taggart, James
AU  - Torner, Evan
PY  - 2003/01/01
TI  -  H-89 Inhibits Serotonin Induced Short-Term Facilitation in the Crayfish Neuromuscular Junction
JF  - Pioneering Neuroscience; Vol 4 (2002)
KW  - 
N2  - Eric R. Kandel and his colleagues' composite research on serotonin (5-HT) in  Aplysia  emphasizes serotonin’s heterogeneous effects as a neurotransmitter on paired-pulse facilitation, since 5-HT not only opens up Ca 2+  spikebroadening channels and Na-K channels to increase excitatory post-synaptic potentials (EPSPs), but also activates an independent protein kinase A (PKA) process of neurotransmitter regulation near the synaptic membrane. This PKA process increases the amount of neurotransmitter released (Byrne & Kandel, 1996). Since it had not yet been proven that this 5-HT-regulated process existed in more than a handful of other organisms outside of  Aplysia , we set up an experiment to determine whether or not Kandel's PKA process is also present in the crayfish neuromuscular junction. We selectively inhibited the PKA process with N-[2-brommocinnamylamino] ethyl]-5 (H-89) and introduced 5-HT into the extracellular solution, measuring EPSPs to determine if the synaptic facilitation normally increased by 5-HT would be reduced. Our results show that the PKA process does in fact exist in the crayfish muscle neurons, since H-89 reduced the otherwise substantial 5-HT-triggered EPSP enhancement to insignificance. This suggests that Kandel’s discoveries in 5-HT-regulated stimulus-response relationships apply to organisms other than  Aplysia  and suggests that further 5-HT studies on crayfish are relevant in the broader field of research on serotonin and its synaptic effects.
UR  - https://ojs.grinnell.edu/index.php/pnsj/article/view/154