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The uptake of (6,7-3H) 17beta-oestradiol by tissues of the domestic fowl

A limited investigation of the distribution of radioactivity in the tissues of the adult laying hen has been made at differing times after intravenous injection of (6,7-3H) 17β-oestradiol. Uptake by all tissues examined was maximal between 2.0 and 4.0 minutes after injection. There was a marked retention of radioactivity by the oviduct and the liver. Of cerebral tissues examined the uptake of radioactivity was greatest in the pituitary gland. This uptake varied according to the physiological state of the bird. Calculations based on the rates of clearance of intravenous (6,7-3H) 17β-oestradiol indicate that in the adult bird the rate of secretion by the ovary is of the order of 1–2.0 mg oestradiol/24 h.

The uptake of (6,7-3H) 17beta-oestradiol by tissues of the domestic fowl during an ovulation cycle

The uptake of radioactivity by various tissues of the domestic fowl has been studied following a single intravenous dose, at different times during the ovulatory cycle.

It has been found that the pituitary gland showed significant cyclical accumulations of radioactivity, when calculated in terms of dpm/mg wet weight, at different stages in the ovulatory cycle, the greatest accumulation being in the period 12–16 hours before the expected ovulation. The results are discussed in relation to the role of oestrogens in the timing of ovulation. It is proposed that oestradiol acts as a major regulator of the timing of ovulation in the domestic fowl.

The Lack of Absorption of Ingested Bovine Antibody in Humans

In the past few years several articles in professional journals (1, 2, 3) and numerous reports in the public press have claimed that antibodies in cows' milk are absorbed in active form via the human gastrointestinal tract. Further, it has been suggested that by using milk from appropriately immunized cows, this method of passive immunization may be employed with benefit in the treatment of such human diseases as pollen allergies. So attractive is this hypothesis that clinical trials of milk from ragweed pollen immunized cows have been conducted in ragweed sensitive patients without, however, any apparent benefit (4). In these clinical trials the lack of a relatively pure antigen makes it impossible to determine quantitatively the amount of antibody in the milk or in the subject's serum after ingestion of milk, so that all results must be based on subjective observations.