임신토끼의 태자혈액 및 양수로의 Li+ 이동에 미치는 Bromocriptine의 영향

Effect of Bromocriptine on Maternal-Conceptal Transfer of Lithium in Pregnant Rabbits

To investigate the role of prolactin in the transfer of Li+ from the maternal to the conceptal side, we conducted a study on the effect of bromocriptine on the transfer as a function of time. At 26-27th days of gestation, pregnant rabbits were divided into two groups : the control group and the bromocriptine treated group. For the preexperimental preparation, each rabbit of bromocriptine group was pretreated with bromocriptine( 胸Ag body weight) intravenously once a day for 3 days. On the day of experiments, a 150 mM LiCl solution was constantly infused through the maternal jugular vein at a rate of lm^/kg body weight/minute. Maternal arterial plasma, fetal plasma and amniotic fluid concentrations of Li+ were measured after 15, 30, and 60 minutes during the infusion as well as Na+ and osmolarity. The results obtained were as follows. 1) Whether or not bromocriptine was given previously, gradual increase of maternal plasma Li+ concentration resulted in a considerable reduction in Na+ concentration while osmolarity remained constant. 2) The degree of progressive increase in fetal Li+ ratio to that of maternal plasma shown in bromocriptine treated rabbits was same as that of the control rabbits. 3) In both groups, amniotic Li ratio to that of maternal or fetal plasma progressively increased as a function of time. Although mean ratios determined in bromocriptine treated rabits were always higher than those observed in controls, the differences were insignificant after 15 and 30 minutes but reached significant levels after 60 minutes. 4) During the entire course of experiment, amniotic fluid concentrations of Naf, K and osmolarity of the bromocriptine group tended to be higher than those of the control group, but a signifcant difference was noted only in osmolarity by 60 minutes of Li infusion. The above results suggest that * (1) Bromocriptine doesn’ t produce any change in transplacental transfer of Li+, at least, until formulating a constant concentration gradient. (2) A significant increase in accumulation of amniotic fluid Li+ in response to bromocriptine seems to be associated with fetal prolactin depletion and vasopressin stimulation