Does anti-oxidant prophylaxis with melatonin prevent adverse outcomes related to increased oxidative stress caused by laparoscopy in experimental rat model?
BACKGROUND
We hypothesized that prophylaxis with an anti-oxidant should prevent potential adverse outcomes of laparoscopy related to increased oxidative stress in splanchnic organs, including small intestine, liver, and kidneys, and melatonin is the most appropriate agent for this purpose.


METHODS
Twenty-four Sprague-Dawley rats weighing 300 to 350 g were allocated randomly into three groups consisting of eight in each as follows: Group I: gasless (control); group II: 15 mmHg intraabdominal pressure (IAP) with CO2 pneumoperitoneum for 60 min; group III: 15 mmHg IAP with CO2 pneumoperitoneum for 60 min, and melatonin (10 mg/kg) was administered at two occasions, 5 min before insufflation and immediately before the desufflation. In group II and III, rats left resting for 30 min after abdominal deflation, the small intestine (terminal ileum), liver and kidney examples were excised from same locations. The specimens were also obtained using the same time points in group I rats, comprising the control group. The specimens were immediately placed at -80 degrees C for the malondialdehyde (MDA) measurements. In addition, segments of terminal ileum were taken from the similar places in all of the animals for the histological examinations.


RESULTS
Comparisons among the groups revealed that highest mean MDA levels in liver, small intestine and kidney were in the group II, followed by the group III and control group. There was significant difference between mean MDA levels in small intestine, liver and kidney of group II and III (P < 0.0005). However, no significant difference was found between mean MDA levels in small intestine, liver, and kidney of the group III and control group. Mucosa and submucosa were affected significantly in 15 mmHg IAP group (no prophylaxis) when compared with the control and melatonin prophylaxis groups (P = 0.002). However, there was not a significant difference in mean damage score of mucosa, submucosa, and muscular layers in control group when compared to melatonin prophylaxis group.


CONCLUSIONS
This experimental study indicated that melatonin prophylaxis, with anti-oxidant and anti-inflammatory actions, may have an important role in the prevention of potential complications related to oxidative stress injury on splanchnic organs induced by laparoscopy.
Cay
Ali
A
Department of Pediatric Surgery, Karadeniz Technical University Medical Faculty, Trabzon, Turkey. dralicay@yahoo.com
Imamoğlu
Mustafa
M
Unsal
Mesut A
MA
Aydin
Sevim
S
Alver
Ahmet
A
Akyol
Ahmet
A
Sarihan
Haluk
H
D000818:Animals; D000975:Antioxidants / Q000494:pharmacology*; D004195:Disease Models, Animal; D007421:Intestine, Small / Q000378:metabolism / Q000473:pathology; D007668:Kidney / Q000378:metabolism / Q000473:pathology; D010535:Laparoscopy / Q000009:adverse effects*; D008099:Liver / Q000378:metabolism / Q000473:pathology; D008297:Male; D008315:Malondialdehyde / Q000378:metabolism; D008550:Melatonin / Q000494:pharmacology*; D018384:Oxidative Stress / Q000187:drug effects*; D011183:Postoperative Complications / Q000188:drug therapy* / Q000473:pathology / Q000517:prevention & control; D011312:Pressure; D051381:Rats; D017207:Rats, Sprague-Dawley; D015427:Reperfusion Injury / Q000188:drug therapy* / Q000473:pathology / Q000517:prevention & control
D000975:Antioxidants; D008315:Malondialdehyde; D008550:Melatonin