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Updated: Jul 24, 2025

Simultaneous Intracellular Recording of a Lumbar Motoneuron and the Force Produced by its Motor Unit in the Adult Mouse In vivo
Published on: December 5, 2012
Interactive classroom: from motoneuron activity to skeletal muscle contraction and relaxation
Luca Todini1, Laura Menchetti1
1Veterinary Physiology, School of Biosciences and Veterinary Medicine, University of Camerino, Matelica, Macerata (MC), Italy.
Abstract:
Active learning and practices are strongly encouraged or made mandatory by local, national, and European organizations. Therefore, we set up an interactive practical classroom, engaging all of the attending students of the year (n = 47). Each student was assigned a physiological role (marked on a cardboard sign) in the following events: stimulation on motoneuron dendrites, sodium ions (Na+) influx and potassium ions (K+) efflux, action potentials onset and saltatory conduction along the axon, acetylcholine (ACh) neurotransmitter exocytosis following Ca2+ influx, ACh binding to postsynaptic membrane receptors, ACh-esterase action, excitatory postsynaptic potential, release of Ca2+ from the sarcoplasmic reticulum, mechanism of muscular contraction and relaxation, and rigor mortis. A sketch was drawn with colored chalks on the ground outside the room: the motoneuron with its dendrites, cell body, initial segment, myelinated axon, and synaptic bouton; the postsynaptic plasma membrane of the muscle fiber; and the sarcoplasmic reticulum. Students each had their own role and were asked to position themselves and move, accordingly. This resulted in a complete, dynamic, and fluid representation being performed. The evaluation of the effectiveness of the students' learning was limited at this pilot stage. However, positive feedback was received in the self-evaluation reports that were written by students on the physiological meaning of their own role, as well as in the satisfaction questionnaires requested by the University. The rate of students who successfully passed the written exam and the rate of correct answers that included the specific topics addressed in this practice were reported.NEW & NOTEWORTHY We set up an interactive practical classroom, engaging all the attending students of the year (n = 47). Each student was assigned a physiological role marked on a cardboard sign, starting from motoneuron stimulation up to skeletal muscle contraction and relaxation. Students were asked to actively reproduce physiological events, positioning themselves and moving around and onto drawings on the ground (motoneuron, synapsis, sarcoplasmic reticulum, etc.). Finally, a complete, dynamic, and fluid representation was performed.
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