Divining the Unknown

In biology, it has always amazed me that we manage to make any breakthroughs at all. There are so many conflicting theories and confounding variables in biological systems that results are often difficult to replicate or may that may not mean what they first appear. I'm reminded of two different discoveries in neuroscience.

The first discovery was of something very basic to modern biologists, the existence of neurotransmitters. This was accomplished by a scientist by the name of Otto Loewi in a rather famous experiment. He first came up with his idea when he was sleeping and wrote it down in the middle of the night, but when he woke in the morning, he couldn't read what he had written. The second time the idea came to him in the middle of the night, he went directly to his lab and performed the experiment. He stimulated the vagus nerve of a frog's heart bathed in ringers solution. The bath was connected to another bath with another frog's heart that had no vagus nerve attached. Acetylcholine, released from the vagus nerve of the first heart, slowed both hearts. Loewi claims that he did the experiment on Easter morning, but that's where chance comes into play. No other scientist could replicate the results for almost a year until the weather was cold enough for the experiment to work, making the Easter claim unlikely. Had the experiment been performed later in the year, he wouldn't ever have become the father of neuroscience as he is today.

The second discovery was more of a war between two scientists, one Ramon Y Cajal, the other Camillo Golgi. Golgi discovered a stain that seemingly randomly stained a few neurons while leaving most unstained. This is greatly significant because it allows for a more individual viewing of neurons that was not previously possible. Golgi came to a theory that was widely accepted at the time that the nervous system was one continuous body with all of the cytoplasm connected, known as the reticular theory. Cajal, on the other hand, proposed and supported the neruon doctrine, in which the nervous system is made up of many cellular units called neurons. His theory proved to be correct, but with the stain as the only evidence, both theories were equally valid because it could just be certain regions of a syncitium that were being stained, upholding Golgi's theory or it could be individual neurons, upholding Cajal's theory. The two of them were very bitter about their differences, which made discussion on the matter difficult. Both based their completely different conclusions on seeing the same thing under a microscope, which gets back to my wonderment about conflicting theories.

It seems odd to me that so few people know about Cajal. He's one of the most prominant people in the study of the nervous system. He was the first to propose too many theories to count, most of them validated over time, yet no one outside of the field seems to know about him. Golgi, on the other had, has a stain named after him as well as the Golgi apparatus, which everyone learns about in high school biology. It's kind of a shame that Cajal's name largely goes unmentioned. I can understand Loewi's name going mostly unknown since most people don't care about the discovery of each neurotransmitter, but Cajal is such a giant in his field. The neuron doctrine is a basic idea in biology that every decent biologist understands.