The other important result at that time was we demonstrated the transmitted release was quantized, it was not high, it was mean quant of about 3 or 4, which gradually increased with time and culture, but that was just like the mature neuromuscular junction. I focused more and more on the accumulation of acetylcholine receptors. Why did that occur and was it really focused on?
We published two papers in 1979, which shaped my career, my reputation, and set the direction for future research. One was a biochemical paper with Tom Jessell, who had joined the lab two years earlier from England. He was in pharmacology and was comfortable with biochemical procedures. He was using fairly standard approaches of gel filtration and ion exchange chromatography. We purified a factor from the chick brain and spinal cord, which could increase the number of acetylcholine receptors on cultured muscle somewhere between 4- and 10-fold, very exciting to me.
The other paper was with Eric Frank, who was a wizard. He was the son of Karl Frank, who was the chairman of the lab of neurophysiology [at the NIH] and a brilliant physiologist, very involved in spinal cord analysis. Eric had been at Reed College and then came to the NIH, and was a gifted, I really mean gifted, experimentalist. He had set up a system so that he can precisely, within a couple of microns, place the electrode filled with acetylcholine next to a recording electrode, eject the ACh and know exactly what the sensitivity was within a 5- to 10-micron span. He had so much electronics set up and he would step on a pedal and that would eject the ACh, turn the oscilloscope on and get the cameras moving. I told him that that pedal was so magic that I could hear the toilets in the hallway flush whenever he stepped on that pedal, he controlled so many different things. It was really quite amazing.