Lars Thomsen obtained his Ph.D. degree from Copenhagen University in Neurophysiology on the topic “Characterization of the enteric nervous system in the porcine small intestine”. A work that required surgical skills in dissecting sheets of neuronal tissue from a large animal with gut physiology resembling humans whereas the vast amount of previous work had been done on the rodent guinea-pig. Hereto, sharp electrodes with tip-diameters had to be freshly melted from borosilicate glass to obtain tip diameters of less than 0.1 µm for easy impalements in neurons. Under x200 times magnification working on an anti-vibration table, he inserted these electrodes into the cytosol of living neurons mounted in the microscope using water-hydraulic micro-manipulators.
The main resulting paper was published in Journal of Physiology which is regarded as the top paper for physiological research with the title: “Electrophysiological properties of neurones in the internal and external submucous plexuses of newborn pig small intestine“