title: Direct venous-arterial transfer of 125I-radiolabelled relaxin and tyrosine in the ovarian pedicle in sheep.
abstract: 125I-labelled relaxin and tyrosine were infused into the ovarian vein to investigate transfer to branches of the ovarian artery at the ovarian pedicle in sheep. The ovarian arteries supply the ovary, the oviduct, and the tip of the uterine horn. An exchange of relaxin (n = 24) and tyrosine (n = 18) was observed in blood samples collected from all branches of ovarian arteries. This is expressed as a ratio of radioactivity greater than 1 between jugular venous blood plasma and arterial blood plasma. The average ratio (+/- s.d.) over the total infusion period of 1 h was 1.42 (+/- 0.35) for relaxin and 1.69 (+/- 0.38) for tyrosine with maximal values up to 4.9 and 2.9, respectively. Of the total amount of substance infused (348 pmol/h), 0.22% of the relaxin and 1.19% of the tyrosine reached the adjacent arteries directly. From these investigations it is concluded that molecules with a molecular weight of approximately 6000 can be transferred directly from veins to arteries at the ovarian pedicle, and the efficiency of this exchange does not only depend on molecular size.
mesh_terms: D000818:Animals; D005260:Female; D007457:Iodine Radioisotopes; D010053:Ovary / Q000098:blood supply*; D012065:Relaxin / Q000097:blood*; D012756:Sheep; D014443:Tyrosine / Q000097:blood*
chemical_list: D007457:Iodine Radioisotopes; D014443:Tyrosine; D012065:Relaxin