As many of us go through our daily routines of coffee self-administration, here a few interesting studies on caffeine and the nervous system.
In 1990 three researchers from Stony Brook University studied the patterns of calcium propagation in the cytosol and nucleus after influx through voltage-dependent channels, and from caffeine-sensitive intracellular stores. They studied dissociated bullfrog sympathetic neurons under voltage-clamp conditions, and scanned the cells using confocal microscopy. Most interestingly, they observed that the spread of calcium through the cytosol lead to large and persistent increases in intranuclear calcium. This phenomenon is even more pronounced when cytosolic calcium is released using caffeine from intracellular stores. This leads the researchers to speculate on the possible role of calcium in mediating the long-term structural and functional changes of neurons following neuronal stimulation.
For a final coffee fun-fact, let's throw it all the way back to 1885, the oldest publication on caffeine recorded in PubMed. It's a just a few paragraphs, but worth noting. A Scottish doctor reports in the British Medical Journal on the use of caffeine as a cheaper alternative to cocaine, as a local anesthetic of course. This is the publication of a negative result (as clearly stated in the last paragraph), something we don't see very often!
Hernandez-Cruz A, Sala F, Adams PR (1990) Subcellular calcium transients visualized by confocal microscopy in a voltage-clamped vertebrate neuron, Science (247) p 858-862.
Robertson DA (1885) Note on the effects of the local application of caffeine on the conjunctiva, The British Medical Journal (1) p17.