Cardiology and Angiology: An International Journal 5(3): 1-7, 2016, Article no.CA.24353 ISSN: 2347-520X, NLM ID: 101658392 SCIENCEDOMAIN international www.sciencedomain.org Histomorphological Study of Effects of Oral Administration of Cadmium Nitrate on Heart of Adult Wistar Rats S. A. Adelakun 1*, O. O. Oyewo 1, O. D. Omotoso 2, N. O. Amedu 2 and U. P. Idoko 2 1Department of Anatomy, Faculty of Basic Medical Sciences, Ladoke Akitola University of Technology, Ogbomoso, Oyo State, Nigeria. 2Department of Anatomy, Faculty of Basic Medical Sciences, Kogi State University, Anyigba, Kogi State, Nigeria. Authors’ contributions This work was carried out in collaboration between all authors. Authors ODO, SAA, NOA, UPI and OOO designed the study, wrote the protocol and wrote the first draft of the manuscript. Authors SAA, ODO, NOA, UPI and OOO managed the literature searches and analyses of the study performed the spectroscopy analysis. Authors SAA, ODO and OOO managed the experimental process. Authors SAA and ODO identified the species of plant. All authors read and approved the final manuscript. Article Information DOI: 10.9734/CA/2016/24353 Editor(s): (1) Luca Masotti, Internal Medicine, Cecina Hospital, Italy and Post-graduate School in Geriatrics, University of Siena, Italy. (2) Wilbert S. Aronow, University of California, College of Medicine, Irvine, USA. Reviewers: (1) Anonymous, National Research Centre, Egypt. (2) James Adams, USC School of Pharmacy, USA. (3) Ming Zhao, University for Nationalities, Tongliao, China. (4) Zar Chi Thent, Universiti Teknologi MARA, Malaysia. Complete Peer review History: http://sciencedomain.org/review-history/14621 Received 15 th January 2016 Accepted 9th April 2016 Original Research Article th Published 13 May 2016 ABSTRACT Cadmium nitrate occurs as a colorless solid. It is soluble in dilute acids and ethanol, acetone, water, diethyl ether, and ethyl acetate. This study examined the effects of Oral Administration of cadmium nitrate on histomorphology of the heart of adult wistar rats. Twenty (n=20) adult wistar rats of both sexes randomly divided into four groups (A-D) of five (n=5) rats each; Rats in group A which served as control were given 10 ml/kg/day of distilled water for 21 days. Rats in group B, C, and D (cadmium nitrate CdN group) were given 150 mg/kg/bw of CdN, 225 mg/kg/bw of CdN and 300 mg/kg/bw of CdN administered orally through an orogastric cannula into the stomach via the esophagus, once a day, for twenty one consecutive days. The heart of each rat was harvested and weighed before fixed in 10% formal saline for histological procedures. Results revealed normal _____________________________________________________________________________________________________ *Corresponding author: E-mail: [email protected]; Adelakun et al.; CA, 5(3): 1-7, 2016; Article no.CA.24353 histological architecture in control while the experimental rats showed inflammations, distortions, congestions, and degenerative changes in myocardium tissue. The heart weight significantly increased in treated group while compared with the control group. Observed effects may therefore cause cardiovascular disorder. Keywords: Heart; cadmium; rat; orogastric; histomorphology; ethanol. 1. INTRODUCTION muscle (myocardium), lined and surrounded by membranes-endocardium and pericardium. It is Heavy metals are individual metals and metal divided by a septum into right and left halves. compounds that can impair human health [1]. The endocardium is a thin internal layer Among the heavy metals cadmium is a very (endothelium and sub endothelial connective genotoxic metal. Numerous studies have shown tissue) or living membrane that cover its values. that genotoxicity of Cd is directly related to its The myocardium is a thick middle layer that is effect on structure and function of DNA, which composed of cardiac muscle while the may be determined using a number of laboratory epicardium is a thin external layer formed by the methods [2-4]. In plants, cadmium is known to visceral layer of serous pericardium [23]. inhibit seed germination and root growth [5,6] and induces chromosomal aberrations and The present study was therefore designed to micronucleus formation [7]. Cadmium (Cd) is a carry out histo-morphological Study of Effects of highly toxic element and is naturally present in all Oral Administration of Cadmium Nitrate on Heart parts of the environment, which includes; food, of Adult Wistar Rats water, and soil [8] and by World Health Organization is major concern for public health 2. MATERIALS AND METHODS [9]. It is a non-essential element and has a half- life which is extremely persistent in the 2.1 Cadmium Nitrate environment [10,11]. Human are at risk to cadmium exposure through the food chain 2.1.1 Procedure because cadmium is not degraded in the environment [12]. Cadmium accumulates in The cadmium nitrate in this research was organ it enters, affecting the cell physiology and purchase from pharmaceutical shop in Yaba growth [13,14], induces disorders in the Lagos, Lagos State, Nigeria in January 6, 2015 hormonal and cellular immune responses and it was taken to Anatomy Laboratory of [15-17]. Department of Anatomy, College of Medicine, University Of Lagos, Idi-Araba, Lagos, Lagos Cadmium is the cause of various diseases State, Nigeria and were authenticated by a staff including cancer, respiratory disease and in the Department of Chemistry University of cerebrovascular diseases, especially the rates of Lagos, Lagos state Nigeria. popular mortality due to these diseases are higher in cadmium contaminated areas than 2.1.2 Animals and diet those areas which are not cadmium contaminated. Breast cancer and endometrial Twenty (n=20) adult wistar rats of both sexes cancer are also associated with chronic exposure were obtained from a breeding stock maintained to cadmium [18,19]. in the animal house, the animal had free access to rat chow and tap water and they were Cadmium nitrate occurs as a colorless solid. It is randomly divided into four (4) groups (A-D) of very soluble in dilute acids and soluble in five (n=5) rats each in a separate room at a ethanol, acetone, water, diethyl ether, and ethyl constant temperature (22.0±1.0ºc) under a 12 h acetate [20]. Cadmium nitrate is available in light/dark cycle. Rats in group A which served as technical and reagent grades with a purity of control were given 10 ml/kg/day of distilled water 99% or higher [21]. for 21 days. Rats in group B, C, and D (Cadmium Nitrate group) were given 150 mg/kg/bw The heart is a muscular organ that circulates the cadmium nitrate, 225 mg/kg/bw of cadmium blood through the vessels to different parts of the nitrate and 300 mg/kg/bw of cadmium nitrate body [22]. The apex is directed anteroinferiorly administered orally through an orogastric toward the left. Its wall consists largely of cardiac cannula into the stomach via the esophagus, 2 Adelakun et al.; CA, 5(3): 1-7, 2016; Article no.CA.24353 once a day respectively, for Twenty one (21) day after which they were transferred to 70% consecutive days. The average daily oral intake alcohol for dehydration. The tissues were passed of cadmium by non-smokers living in unpolluted through 90% alcohol and chloroform for different areas was estimated to 10–25 µg [24] while in durations before they were transferred into two Laboratory animals oral LD50 values for mice changes of molten paraffin wax for 20 min each and rats range from 60 to over 5000 mg/kg of in an oven at 570 C. Serial sections of 5 µm thick body weight [25]. All experimental investigations were obtained from a solid block of tissue and were done in compliance with humane animal as were stained with haematoxylin and eosin stains, stated in the “Guide to the care and use of after which they were passed through a mixture Laboratory Animals Resources”. National of equal concentration of xylene and alcohol. Research Council, DHHS, Pub.No NIH 86-23 Following clearance in xylene, the tissues were [26] and in accordance with the guideline oven- dried. Photomicrographs were taken with a and approval of Nigeria Medical Ethical JVC colour video digital camera (JVC, China) Association for Accreditation of Laboratory mounted on an Olympus light microscope Animal Care. [Olympus UK Ltd, Essex, UK] to demonstrate the liver damage. 2.2 Animal Sacrificed and Sample Extraction 2.4 Statistical Analysis Twelve hours(12 hours) after the administration Data are expressed as mean ± S.D. Statistical of the last cadmium nitrate, the rats were at the analyses were perfumed with SPSS software. time of sacrifice first weighed and then cervical P < 0.05 was considered statistically significant. dislocation was carried out following ethical Overall Differences between groups were humane animal euthanasia which was adopted determined by one-way ANOVA. with expertised cervical dislocation. The abdominal cavity of each rat was opened up 3. RESULTS through a midline thoracic incision to expose the heart. The heart was excised and weighed; the 3.1 Mean Body Weights, Heart Weights in heart was weighed with an electronic analytical Experimental and Control Rats and precision balance. The heart of each animal was fixed in 10% formol-saline for histological As showed in Table 1: It indicates the average examination. [BA 210S, d=0.0001- Sartoriusen body weights of the rats before and after the GA, Goettingen, Germany]. experiment. The control rats gained weights significantly (p<0.05) from the beginning of the 2.3 Histological Procedures and Analysis experiment to the end of the experiment. Body weights of experimentatyl rats decreased as This was done as described by Ogunlade et al. compared to the control group. The mean heart [27]. Briefly, the organs were cut on slabs about weight of the rats significantly increased as 0.5 cm thick and fixed in 10% formol saline for a compared to the control (Table 2).