A new method for the isolation of myenteric plexus from the newborn rat gastrointestinal tract

The myenteric plexus is not only essential for gastrointestinal functions, but it is also a very interesting model for the study of neuronal circuits and neuron-glial interrelationships and may be a valuable source of donor tissue, for grafting into different regions of the central nervous system. For both grafting and culture procedures it is a great advantage to obtain the maximum amount of tissue. To date, most studies have isolated the myenteric plexus by manual microdissection after collagenase digestion. Using this method, it has only been possible to obtain relatively small amounts of the myenteric plexus, mostly from the cecum and proximal colon of the guinea-pig or rat. We present here a new method, which enables much greater quantities of the plexus from the small intestine and colon to be obtained. The myenteric plexus of the entire small intestine can be isolated by a combination of enzymatic digestion and mechanical agitation. The method works from birth up to 3 week old pups, and with some modifications tissue from older or even adult animals can also be processed. Another advantage over the microdissection method is that the myenteric plexuses of the different parts of the intestine can be cultured and studied separately.