Conditions affecting prolonged maintenance of mouse and rat colon in organ culture.

The effect of variations in culture conditions on survival of fragments of mouse and rat descending colon in organ culture was studied by morphological and functional criteria. A combination of conditions demonstrated to be beneficial permitted maintenance for at least 35 days. These included: a gaseous environment of 95% O2:5% CO2, an attachment matrix consisting of a Metricel GA-4 membrane (pore size, 0.8 mu), intermittent exposure to the gas and fluid phases by rocking in 5 ml medium and supplementation of the medium with 1.0 microM dexamethasone and 10% FBS. During this time, the crypt structure of the mucosal epithelium was well preserved, and DNA synthesis in the crypts and mucin production in the crypts and superficial epithelium continued. In addition, the synthetic trophic hormone, pentagastrin, stimulated DNA synthesis in the mucosal epithelium of mouse colon fragment in short-term organ culture.