American Journal of Biomedical Research, 2019, Vol. 7, No. 1, 14-20 Available online at http://pubs.sciepub.com/ajbr/7/1/4 Published by Science and Education Publishing DOI:10.12691/ajbr-7-1-4 Effects of Lead Treatment on Healing of Mucosal Injury in the Colon of Wistar Rats: A Biochemical and Histological Study Adeleye Gbenga Sunday 1,* , Oseni Olatunde Abbas 2 , Odesanmi Olalekan 3 , Ajayi Akande Oladimeji 1 1 Department of Physiology, College of Medicine, Ekiti State University, Ado Ekiti Nigeria 2 Department of Medical Biochemistry, College of Medicine, Ekiti State University, Ado-Ekiti 3 Department of Biochemistry, Faculty of Science, Ekiti State University, Ado Ekiti *Corresponding author: sunday.adeleye@eksu.edu.ng, adeguyton@gmail.com Received Janaury 17, 2019; Revised March 21, 2019; Accepted April 10, 2019 Abstract This research work was aimed at studying the impact of chronic lead exposure on healing of experimentally induced Colitis in Wistar rats. The results will increase our understanding of the roles played by heavy metals toxicity in colitis disease initiation, progression and remission. Cases of environmental lead exposure and its effects on the health of humans and animals are becoming more noticeable globally. However, there is paucity of information on how chronic lead exposure interferes with healing of chemically–induced colitis in rats. Sixty male rats (80-100 g) were randomly and equally divided into control (tap water), low dose and high dose (Lead acetate, 100 ppm and 5,000 ppm respectively, p.o.) groups. Twenty weeks post- treatment, colitis was induced in the colon of the animals by injection of 6% Acetic acid solution via a modified Teflon cannula into the colon of the animals. Colitis (stool) scoring was done between in all groups. Histological slides were prepared on selected days. The results showed that in control animals, coltis healing was complete on day 12 compared to day 22 in treated animals. In conclusion, exposure of rats to Lead delayed colitis healing, buttressing the fact that people with inflammatory bowel disease should avoid Lead exposure. Keywords: lead, colitis, acetic acid, colon, rats Cite This Article: Adeleye Gbenga Sunday, Oseni Olatunde Abbas, Odesanmi Olalekan, and Ajayi Akande Oladimeji, “Effects of Lead Treatment on Healing of Mucosal Injury in the Colon of Wistar Rats: A Biochemical and Histological Study.” American Journal of Biomedical Research, vol. 7, no. 1 (2019): 14-20. doi: 10.12691/ajbr-7-1-4. 1. Introduction The Gastrointestinal tract (GIT) is a very important system in the body, being the only natural route through which nutrients and other biological and non-biological molecules (condiments, drugs, e.t.c) needed for growth and development are ingested. These substances enter the stomach from the mouth via esophagus where they are digested and/or absorbed. After leaving the stomach, partially digested food, digestive enzymes, water and a myriad of other substances move to the small intestine and on to the large intestine or colon where absorption of significant quantities of water, minerals, vitamins and other substances takes place [1]. The reception of products of digestion as well as the absorption that occurs in the colon makes it to be susceptible to normal “wear and tear” processes. However, there are some mechanisms found in the colon that protect it from these assaults and minimize the damage that would otherwise have occurred. Several disorders affect the GIT such as ulcers, gastritis, ulcerative colitis, Crohn’s disease, etc. Ulcerative colitis and Crohn’s disease are amongst the most challenging human illnesses globally [2] however it is more common in the developed world [3] and difficult to cure pharmacologically [4]. Colitis is defined as an inflammation of the colon. Ulcerative colitis is a form of colitis, a disease of the colon (large intestine), that includes characteristic ulcers, or open sores. Chronic and extensive ulcerative colitis predisposes to colorectal cancer, therefore colitis should be seen as a serious health condition worthy of detailed research if only to minimize the possiblility of it degenerating into more critical conditions [5]. Current literature suggests that several immune, genetic and environmental factors influence both the initiation and continuation of the disease [6]. The main symptom of active disease is usually constant diarrhea mixed with blood and usually of gradual onset. Healing of any gastrointestinal ulceration and/or inflammation involves some or all of the following processes: granulation tissue formation, re-epithelialization, tissue remodeling, cell proliferation, cell division, cell hypertrophy, fibroblast migration, collagen deposition,