Placental trophoblast plasma membrane (TPM) system L and A activities following trophoblast-specific Deptor knockdown in mice. At E18.5, animals were sacrificed, and placentas from each litter were weighed, pooled, and homogenized. TPMs were isolated. System L (A) and system A (B) transporter activities were determined using isotope-labeled substrates and rapid filtration techniques in TPM isolated from NSS and Deptor KD placenta at E18.5. Each dot represents litter mean value (n = 8 litters represent 29 NSS conceptuses and 32 Deptor KD conceptuses). Values are expressed as means ± SEM. All placentas of each genotype in a litter were pooled prior to isolation of TPM. Litter mean values for NSS and Deptor KD conceptuses compared by paired Student’s t-test. NSS, nonsense sequence (control) group.