SERUM PROTEIN-BOUND IODINE AND SERUM LIPID CHANGES IN THE BABOON (PAPIO URSINUS)

Abstract

SUMMARY A study comprising 258 duplicate estimations of serum protein-bound iodine (PBI), total lipids, total cholesterol, lipid phosphorus and cholesterol/lipid phosphorus (C/P) ratios has been made in eleven adult female baboons during forty-one menstrual cycles. Comparison of these results with ninety-six corresponding estimations on thirteen adult male baboons observed over the same period indicates that: (a) The serum PBI and serum lipids in the female baboon fluctuate in rhythm with the phases of the menstrual cycle. Cyclical changes are not present in the male. (i) Serum PBI rises from the time of ovulation and reaches a peak just before perineal rest. (ii) Serum cholesterol rises from ovulation to the mid-point of deturgescence and drops rapidly afterwards to its initial level. (iii) Lipid phosphorus rises steadily during turgescence, reaching a maximum level after ovulation, and declines slowly to a minimal value at perineal rest and menstrual bleeding. (iv) The C/P ratio drops gradually during turgescence to ovulation and rises subsequently in deturgescence. (v) No rhythmic tendency of statistical significance was observed in total serum lipids. (b) The iodine/albumin ratio remains about constant during the entire cycle. (c) No reciprocal relationship was found between the PBI and cholesterol of any of the other serum fat fractions. The changes in serum PBI and serum lipids in the baboon's menstrual cycle differ from those described in the human female.