Teaching the modes of Ca2+ transport between the plasma membrane and endoplasmic reticulum using a classic paper by...

This teaching article uses the report by Kwan et al., "Effects of methacholine, thapsigargin, and La(3+) on plasmalemmal and intracellular Ca(2+) transport in lacrimal acinar cells," where the effects of Ca(2+)-mobilizing agents in regulating Ca(2+) fluxes were examined under various conditions. Upper-level undergraduate and new graduate students in physiology are the targe audience. Teaching and learning points are put forth in this article to illustrate 1) the characteristics of methacholine- and thapsigargin-induced Ca(2+) responses, 2) the different endoplasmic reticulum Ca(2+) stores accessible to methacholine and thapsigargin, 3) the inhibitory effects of La(3+) on Ca(2+) extrusion and Ca(2+) influx, and 4) the facilitatory role of La(3+) on endoplasmic reticulum Ca(2+) recycling. Each of the above concepts is first explained with references to the figures adapted from the original article. A list of student learning questions then follows, where the answers are found in the teaching notes for the instructors. It is the objective of this article to make both teaching and learning Ca(2+) regulation a rewarding experience for all.