Transfer placental fluid

Placental Viability. Fluid Transfer. Fluid transfer from the fetal to the maternal circulation of more than 2 ml/min of blood solution was... 

Specific barriers may serve to limit dmg distribution. The placental barrier is of obvious importance to dmg action in the fetus. Dmg transfers across the placenta primarily by Hpid solubiHty. Hence, this barrier is not particularly restrictive. Similarly, the Hpid solubiHty of a dmg is a primary deterrninant in access to the brain and cerebrospinal fluid. Generally, hydrophilic or charged dmgs can also penetrate to these latter areas, but the result is slow and incomplete. The blood brain barrier is composed of cells having tight junctions which are much less permeable to solutes than are the endotheHal cells of other tissues. 

Placental transfer of di(2-ethylhexyl) phthalate has been observed following intra-peritoneal administration of di(2-ethylhexyl) [car6o y/- C]phthalate on gestational day 5 or 10 in rats (Singh et al, 1975). The dams were killed at 24-h intervals starting on days 8 and 11 until day 20 of gestation. Radioactivity was detected in fetal tissues, amniotic fluid and placenta at all time points. The radioactivity peaked at 48 h and declined rapidly thereafter. The concentration was less than that in maternal blood and less than 1% of the administered dose. 

Note Parameters refer to cynomolgus monkey. Italicized parameters are also available for the marmoset model. Parameters for a placental transfer study in cynomolgus monkey and marmosets comprise TK/PK samples, such as maternal blood before (animal not sedated) or at (animal sedated) cesarean section, blood from umbilical cord, and collection of amnio tic fluid. 

The described procedure may be seen as a minimum for investigation of the placental transfer. Of course, whenever necessary or useful, the procedure may be enlarged by additional time points and organs/tissues/body fluids (such as ovary, kidney of dams) to be investigated. 

C6. Chryssikopoulos, A., Mantzavinos, T., Kanakas, N., Karagouni, E., Dotsika, E., and Zourlas, P. A., Correlation of serum and follicular fluid concentrations of placental protein 14 and CA-125 in in vitro fertilization-embryo transfer patients. Fertil. Steril. 66, 599-603 (1996). 

Also the placenta has a barrier for hydrophilic and very lipophilic compounds, which is comparable to the blood-brain barrier. Correspondingly, quantitative relationships could be derived for the placental transfer ratios TR of various drugs (eq. 170, recalculated) [775]. The diffusion of drugs into milk and prostatic fluid has been reviewed [472, 761]. 

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