Effect of L-arginine supplementation on growth hormone and insulin-like factor 1 in pregnant mice

Abstract

L- Arginine (L-Arg) is an essential amino acid in physiological fluids. The purpose of this study was to test the effect of dietary L-arginine supplementation in pregnant mice and its role in improving fetal growth. Sixty-six female mice with body weight (28-36 g) were divided into three groups (A, B, C) when pregnancy occurs. Each group was divided into 2 subgroups according to administration: 1-7 days and 1-15 days of pregnancy as followed as:  group (A) 22 pregnant mice of this group gave normal saline (0.9% NaCl): 13 mice treated from (1-7 days) and 9 mice treated from (1-15 days).  Group (B) 22 pregnant mice of this group gave 200mg of L-arginine /kg:13 mice treated from (1-7 days) and 9 mice treated from (1-15 days). Group (C) 22 pregnant mice of this group gave 400mg of L-arginine /kg:13 mice treated from (1-7 days) and 9 mice treated from (1-15 days). after birth, blood by direct cardiac puncture were collected. Data were analyzed shows that the numbers of total fetuses born did not differ (P=0.703) among control and L-arg. supplemented groups with 200 mg/kg and 400 mg/kg during the gestational period (1-7 days). also, non-significant differences (P=0.681) in the number of live foetuses among control and L-arg. supplemented groups with 200 mg/kg and 400 mg/kg during the gestational period (1-15 days). The weight of live fetuses was significant increased (P≤0.01) in L-arg. supplemented groups with 200 mg/kg and with 400 mg/kg when compared with that of the control group during the gestational period (1-7 days). Additionally, there was a significant increase (P< 0.01) in L-arg. supplemented groups with 200 mg/kg and 400 mg/kg when compared with the control group during the gestational period (1-15 days). Hormonal assays, there was a significant (P< 0.01) increase in IGF-1 level in L-arg. supplemented groups with 200 mg/kg and 400 mg/kg during a gestational period (1-7 days). Whereas during a gestational period (1-15 days) also the results showed that there was a significant (P≤0.01) increase in the mean of IGF-1 level in L-arg. supplemented groups with 200 mg/kg and 400 mg/kg in compared to the control group. The result showed that no significant (P=0.492) correlation in growth hormone concentration among the groups during a gestational period (1-7 days).  While during a gestational period (1-15 days) there were significant (P≤0.05) differences between the mean value of growth hormone in the control group was found to be (12.47 ±0.08), in L-arg. supplemented groups with 200 mg/kg it was (18.21 ±3.90), and groups with 400 mg/kg was (13.78 ±0.37).