STUDY THE N - ACETYLCYSTEINE EFFECTS ON GASTRECTOMY AND SOME BIOCHEMICAL PARAMETERS IN DOGS

The project of research was carrying out to study the effect of N-acetylcysteine on the wounds which developed in the stomach after gastrotomy. Dogs were used in this study as experimental animals. Dogs were divided into two groups' treatment and control; each group contains 5 animals. The surgical incision was closed by two layers of sutures using absorbent sutures then closed the muscle and skin using traditional steps. The treatment group was treated using 3% of N-acetylcysteine fluid topically on site of operation, as well as N-acetylcysteine (140 mg/kg/ day) was administrated orally for 7 days. Gross examination and clinical signs were recorded after 7 days of operation. Blood samples were collected before the surgery and 7 days after the surgery for complete blood studies on blood samples in both groups. Additionally, tissue samples were taken from operation areas to study the histological change. Results of this study show that the healing of treated groups with N-acetylcysteine was disappeared after 3 days while in control groups the healing sings continued until 7 days after surgery. The mucous membranes in the group treated with N-acetylcysteine were healthier comparative to the control group after 7 days treated showed the normal arrangement of tissue layers and no adhesion or increasing in collagen affected on wound healing in the stomach, while the increase in HDL means increasing in improvement factors and accelerate healing in the site of operation. Infectious diseases, inflammatory disorders, and the alterations in lipoprotein levels and lipid in the plasma of blood are very similar to decreasing in plasma HDL which consistently observed.


INTRODUCTION
N-Acetyl cysteine is inexpensive medication and safety uses, is commercially accessible for long-time. N-Acetyl cysteine was not present naturally but the cysteine is amino acid present normally in meals like chicken and turkey meats, eggs, yogurt and garlic. NAC is a well-tolerated mucolytic drug which moderates clinging secretion of mucous and enhances activity of glutathione S-transferase. The oral administration of this drug, reaction of deacetylation of NAC happens, while passage it through the small intestine as well as liver, thus its 4-10% decreased in bioavailability by NAC which stimulates biosynthesis of glutathione, directly acts as a free radicals scavenger and also promotes detoxification. It acts as powerful antioxidant and a potential treatment option to the diseases (in the diseases when the generation of free radicals) (1,2). NAC acts to prevents apoptosis of cells and oxygen-related genotoxicity by increasing levels of intracellular glutathione in endothelial cells and decreasing depolarization of mitochondrial membrane (3). Surgeons of small animal routinely perform the gastrointestinal tract (GI) wounds for neoplasm removal or a foreign body for correction of gastric dilatation-volvulus or to relieve obstruction of the colonic and intestinal tract.
Unlike dehiscence of a skin wound, this is often easily remedied with appropriate in the local wound treatment, the dehiscence of wounds of the gastrointestinal tract which leads to infection by bacterial causing peritonitis and increment of the mortality (4). So far, reoperation required for septic peritonitis, techniques patching for the leakage sites, resuscitation of aggressive fluid and based on culture and sensitivity appropriate the antibiotic therapy. Surgical techniques of innovative such as uses material accelerate healing and prevent adhesion might be necessary to decrease the death rate. In this clinical study, we want to decrease adhesion between the stomach and other organs in the site of operation and in the same time accelerate healing of operation site. This research aimed to study the effects NAC on site operation in gastrostomy in dogs and also its effects on some biochemical parameters.
Animals of experiment: Ten dogs were involved in the study. The age of dogs was between (8-9) months old and an average weight of 20 kg (range 15-25.4 kg). The dogs were randomly divided into two groups (five animals each). No observed differences were showed between the groups with respect to age and weight. The dogs were housing in the facility of the animal at Basra University in Veterinary Medicine College. They provided free access to food and water. They were determined to be healthy based on physical examination findings.

5-Serum triglyceride measurement (TG):
measured by using a special chemical kit based on Stein

6-Estimation of serum lipoprotein cholesterol:
cholesterol measured as follow total cholesterol was enzymatically measurement of TC is presented The concentration of serum triglyceride was types of lipoprotein

A-Serum High-Density Lipoprotein Cholesterol (HDL-C):
The HDL is play important role in the lipid metabolism is the uptake and transport of cholesterol from peripheral tissues to the liver through a process known as reveres cholesterol transport (6).

B-Serum Low-Density Lipoprotein Cholesterol (LDL-C):Serum LDL concentration
calculated can be by method mentioned by Ram (9).
Statistical Analysis:Expressed of the results were as mean ± standard deviation (M±SD).
By using independent t-test analyzed for the experiment; the statistical analysis was using One-way ANOVA by SPSS (Special Program for Statistical System) version 21.0. The least significant difference test (LSD) was used to determine the differences between groups in ANOVA-test, the level of significant set on p< 0.05 (11).
Histopathological Study: The histopathological study was performed after seven days from surgical operation. Specimens, which taken from the site of operation of stomach, were fixed in 10 % formalin and the tissue was processed in ordinary ways and then stained with Hematoxyline -Eosin (H & E) stains (12).

RESULTS
Clinical signs Heat, appetite, weight, mucus membrane and heart rate recorded before and after the operation in all animals. In summary heat disappeared after 3 days in treated groups but persisted until day 7 in control groups. Appetite evaluation saw no changes at day 7 in the two groups. Body weight decreased in control groups more than treated groups.
The mucus membrane of two groups after 3 day had had abnormal structure while after 7 days the treated group had less changes compared to control group. Finally, the study did not find any different in heart rate among groups.
Microscopic examination: After 7 days the surgical operation was opened, and Gross examination was performed. In summary, we were found adhesion in control group and healing development in site of operation low, but in treated group only one dog found small adhesion with easy separated also, the site of surgery found in good healing condition (figure 4-treated ,5-Control).

Effect of N-acetylcysteine
The effect of NAC in (table 1)   *large litters denote to significant differences between groups.

Effect of N-acetylcysteine on lipid profile:
The results in table (1) revealed the effect of N-acetylcysteine on total cholesterol (TC) which significantly (p<0.05) decreased after 7days of operation and treatment in G2 compared with control group. Also the results showed significantly (p<0.05) decreased in TG, VLDL and LDL while increased significantly (p<0.05) the level of serum HDL in treated group compared to same group before treatment (0days) and control group. *large litters denote to significant differences between groups.

Effect of N-acetylcysteine on liver enzymes:
In table (2), the results showed the effect of N-acetylcysteine on liver enzymes (ALP, AST and ALT). Significant (p<0.05) decreased in ALP, AST and ALT concentrations in groups treated with N-acetylcysteine compared to G1 group.

Histopathological change:
showed normal structure of stomach control groups fibers adhesion hemorrhage and increase inflammatory cells  (13) .
Clinical signs found heat disappeared after 3 days in the treated group which indicated on inflammation reduced by use NAC, however, in control group heat continued until day The study showed the effect of N-acetyl cysteine on liver enzymes (ALP, AST, and ALT). The decreases significantly in ALP, AST and ALT concentration were found in groups treated with NAC compared to group of control. Elevated liver enzymes are common in liver problems and inflammations in the body these caused due to increased ALP, AST, and ALT but in this study, liver enzyme did not show any changes and treated groups had healthy parameters (18).
The histopathological study after 7 days of the stomach in dogs in treated group with NAC showed normal layers, no adhesion and increase collagen fibers, but the control group showed adhesion fibers on the outer layer of the stomach, hemorrhage and increase inflammatory cells. NAC is a powerful antioxidant agent and a scavenger of free radicals.
NAC in recently, it has anti-inflammatory activities in the cells and tissues. NAC therapy has a dual action as an effective anti-inflammatory, an antioxidant agent and may be a promising therapeutic option for wounds in the stomach (19