Vasoactive Intestinal Peptide vasoactive intestinal polypeptide 50 female 46 Female 44 priority journal 42 controlled study 40 article 34 Humans 28 Pregnancy 28 protein expression 28 Animals 26 Mice 26 human 26 mouse 26 Mice, Inbred NOD 24 Sjoegren syndrome 24 animal model 24 nonhuman 24 Mice, Inbred BALB C 22 Trophoblasts 22 animal experiment 22 interleukin 10 22 trophoblast 22 animal tissue 20 human cell 20 metabolism 20 vasoactive intestinal polypeptide receptor 1 18 Sjogren's Syndrome 16 cell line 16 enzyme activity 16