Pharmacology of Hormonal Polypeptides and Proteins Proceedings of an International Symposium on the Pharmacology of Hormonal Polypeptides, held in Milan, Italy, September 14–16, 1967

It can be concluded (under the specific experimental procedures em ployed) that:- 1) HCG labelled with 1 - 2 atoms of radioactive iodine did not differ sig nificantly from the unlabelled hormone; 2) The ovary alone exhibited a capacity to affix specifically HCG; 3) The amount of radioactive material in the ovary was directly proport ional to the quantity of labelled HCG injected; 4) When the HCG present in the circulation is bound to an antiserum to HCG, the antigen-antibody complex is not concentrated by the ovary; 5) Circulating labelled HCG decreased to 50% within 30 minutes following a single intravenous injection; 6) There are four different phases of ovarian uptake of HCG, namely: the first phase, when there is only an inflow from the circulation and stor age mainly in the follicular envelopes; the second phase, when there is a greater inflow than outflow; the third phase, when the inflow is equal to the outflow; and the fourth period, when the outflow is bigger than the in flow. REFERENCES 1. Lunenfeld, B. and Eshkol, A. Vitamins and Hormones (1967) 25:165 2. Eshkol, A. In: Recent Research on Gonadotropbio Hormones, eds. E. T. Bell andJ. A. Loraine, Edinburgh, Livingstone (1967), p. 202. 3. Eshkol, A. and Lunenfeld, B. Proc. Tel-Hashomer Hosp. (1967) 6:4. ACKNOWLEOOMEN'IS This work was supported in part by a grant from the Population Council, N. Y. , U. S. A. andbyGrantNo.