Morphological and quantitative study of the myenteric plexus of the ascending colon of rats subjected to proteic desnutrition.

We carried out this study with the purpose of contributing on the effects of the proteic desnutrition on the morphological aspects and quantitative analysis of the neurons in the myenteric plexus of the ascending colon of adult Rattus norvegicus. Twenty adult rats were divided into two groups: in one of them, we offered a normal ration with proteic level of 22% (control group) and in the other, a ration with a proteic level of 8% (experiment group) during 120 days. We did the whole-mount preparations for the ascending colon and stained them with the Giemsa technique and the histochemical technique of NADH-diaphorase. The rats with proteic desnutrition showed a body weight, on average, to be 35.1% less than those of the control group, and the colon was on average, 26.8% shorter and 6.7% narrower. Thus, it was to be expected that the colon of animals with proteic desnutrition had a neuronal density 31.62% greater than the rats of the control group. Nevertheless, the difference with the Giemsa technique was on average 18.4%, demonstrating a mean neuronal loss of 13.25%.