Effect of Exogenous Pregnancy Hormones on Gastrointestinal Motility in Female Wistar Rats
[1]
Otamere Harrison Oghogho, Department of Physiology, Faculty of Basic Medical Sciences, College of Medicine, Ambrose Alli University, Ekpoma, Nigeria.
[2]
Aloamaka Chukwuemeka Peter, Department of Physiology, Faculty of Basic Medical Sciences, College of Health Sciences, Delta State University, Abraka, Nigeria.
[3]
Onyesom Innocent, Department of Physiology, Faculty of Basic Medical Sciences, College of Health Sciences, Delta State University, Abraka, Nigeria.
[4]
Ojieh Emeka Anthony, Department of Physiology, Faculty of Basic Medical Sciences, College of Health Sciences, Delta State University, Abraka, Nigeria.
Pregnancy hormones are implicated in gastrointestinal functions, however findings have be variable and in some cases contradictory. This study investigates the effect of exogenous female hormones on the rate of gastric emptying and small intestinal motility in female rats. The study involves 24 adult rats (180 to 200g) assigned to 4 groups fed normal rat chow and water ad libitum throughout the period of the experiment. Group 1 served as control and received no treatment. Groups 2 and 3 were treated intramuscularly with 30ug/kg estrogen and 2mg/kg progesterone respectively while group 4 received the combination of estrogen and progesterone daily for 14 days. After the treatments, all rats were scarified and the stomach and intestine obtained to study the rates of gastric emptying and small intestinal motility following standard laboratory procedures. The results showed elevated serum levels of estrogen and progesterone in the groups treated with various exogenous hormones compared to control. The rate of gastric emptying was significantly higher (P<0.05) in group 4 (0.043±0.007g/min) compared to group 3 (0.022±0.175g/min) and this was significantly higher (p<0.05) compared to group 2 (0.006±0.003g/min) that was similar to the control (0.007±0.005). The rate of small intestinal motility was significantly lower in exogenous sex hormones treated groups compared to the control (2.57±0.15cm/min). Group 3 (1.27±0.49cm/min) had significantly higher (p<0.05) small intestinal motility rate compared to group 2 (0.48±0.19cm/min) that has similar rate with group 4 (0.59±0.41cm/min). These findings indicate that pregnancy hormones may increase gastric emptying but reduce small intestinal motility rates with progesterone producing a stronger influence.
Exogenous Hormones, Pregnancy, Gastric Emptying, “Small Intestinal Motility”
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