Even an old technique is suitable in the molecular world of science: the everted sac preparation turns 60 years old

Abstract

An old proverb states "necessity is the mother of invention." This certainly holds true in science as one pursues research questions. Experimental techniques have evolved as scientists have asked more specific research questions. Indeed, techniques such as the Ussing chamber, the perfused renal tubule preparation, patch-clamp, polymerase chain reaction, and site-directed mutagenesis have been developed over the past 60 years. However, sometimes, simple techniques may be useful and still very informative, and this certainly applies to intestinal physiology. Indeed, Gerald Wiseman and Thomas Hastings Wilson described the intestinal everted sac preparation some 60 years ago. Since then, this technique has been used for numerous research purposes including determining ion, amino acid, water and solute transport across the intestinal epithelium; and drug metabolism, absorption, and interactions in pharmaceutical/pharmacological research and even in education. This article provides a historical review of the development of the in vitro intestinal preparation that led to the everted sac preparation and its use in science.

Gintonin absorption in intestinal model systems

“…This process is driven by passive diffusion via the concentration gradient. In contrast, the everted gut sac system is used to examine the transport of various substances via ex vivo intestinal absorption [14] , [15] , [16] . Recently, we produced a gintonin-specific monoclonal and polyclonal antibodies and developed an enzyme-linked immunosorbent assay (ELISA) for gintonin detection using the monoclonal antibody [17] .…”

Permeability of the fish intestinal membrane to bulky chemicals

“…The intestinal tract was turned inside out and immersed in a buffer solution containing the test chemical, and the amount of chemical that passed through the membrane into the tract was quantitated. This method has been used for rats, mice, rabbits, sheep, chickens, turtles, pigs, and frogs [14][15][16][17] but has been used hardly at all for fish. 18,19) Apart from the everted gut sac method, a vertical or horizontal glass-diffusion cell system can also be used to measure the permeability of biological membranes.…”

Measuring intestinal fluid transport in vitro: Gravimetric method versus non-absorbable marker

“…The in vitro gut sac preparation, involving longitudinal sections of the intestine ligated at one end and filled and emptied at the other via a catheter, is a long standing and popular method for the study of intestinal transport that is still used to address current physiological questions (Hamilton, 2014). With relative technical ease gut sacs permit the simultaneous, straightforward measurement of intestinal solute and water fluxes, and can also be modified to enable the monitoring of electrophysiological parameters (Grosell et al 2005).…”