Showing papers by "Worcester Foundation for Biomedical Research published in 1955"

Development of fertilizing capacity of rabbit spermatozoa in the uterus.

Abstract: BY deposition of sperm into the Fallopian tubes of a rabbit at various times before or after ovulation, it has been found1 that ejaculated or epididymal spermatozoa require about six hours stay in the tubes to acquire their fertilizing capacity. Although sperm incubated in the uterus of a live animal for five hours was found to be capable of fertilization when deposited into the tube, the time requirement in the uterus was not systematically determined. The following experiment provides more direct evidence to show that spermatozoa placed in the uterus also require a definite period of time to develop their fertilizing capacity. However, attempts to develop the fertilizing capacity of ejaculated sperm in vitro have been unsuccessful.

Concerning possible mechanisms of hormone action.

Abstract: Publisher Summary The mechanism by which any hormone acts in terms of the fundamental chemistry and physiology of the cell has yet to be elucidated. This applies equally to all known hormones, whether derived from mammals, plants, or insects. In the case of the mammalian hormones, the poverty of knowledge about mechanisms exists in the midst of a wealth of information concerning hormones, their chemistry, biogenesis, catabolism, and the physiologic processes which they regulate. It is only when the mechanisms of hormone actions are considered that this picture of steady, when not dramatic, advances are changed; here progress appears minimal and the future seems uncertain. If notable successes have not been achieved, this should not be taken to imply that the problem of hormone action has received inadequate attention. This chapter focuses on the mammalian hormones; plant and insect endocrinology are discussed only to the extent that they may throw light upon the major field of interest.

19-Hydroxylation of delta 4-Androstene-3,17-dione and dehydroepiandrosterone by bovine adrenals.

Abstract: Die Aufklarung der Struktur von 19-Oxy-Δ4-androsten-3,17-dion (VI), einer Substanz, isoliert nach Inkubation von Δ4-Androsten-3,17-dion und von Dehydroepiandrosteron mit einem Rinder-Nebennieren-Homogenat, ist beschrieben. Dies ist unseres Wissens die erste Beobachtung der Hydroxylierungin vitro einer angularen Methylgruppe eines Steroids. Mehrere Folgerungen sind erortert.

The biosynthesis of adrenal steroids.

Abstract: Intensive studies of the chemical transformations that adrenocortical tissue can effect with a large variety of steroid substrates have led to the isolation of a large number of products. Some of these products appear to be physiologically rational (e .g . , cortisol derived from progesterone), whereas others (e .g . , allopregnanedione derived from progesterone) can be assigned no physiological role. Because of these varied biosynthetic potencies of adrenocortical tissues, it is well, first, to determine what, in fact, is secreted by the adrenal cortex, and then to consider how the secretory product is manufactured. We have recently reviewed these two major problems in detai1,l. so, in this paper, I should like to confine my attention to: (1) our latest evidence concerning the nature of the human adrenal secretory product; and (2) our present concept of the major operative biosynthetic pathways.

Metabolism of testosterone-3-C14 in the guinea pig.

Abstract: ANDROSTERONE and 3α-hydroxyetiocholan-17-one have been demonstrated to be the principal urinary metabolites of administered testosterone in man (Callow, 1939; Dorfman et al., 1939; Fukushima et al., 1952; and West et al., 1951). Epiandrosterone has been isolated from the urine of a male guinea pig (Dorfman and Fish, 1940) and of a hypogonadal man (Dorfman, 1941) following the administration of testosterone. Since the guinea pig is being used for steroid hormone studies, it would be of interest to know the principal urinary metabolites of testosterone in this species. To this end, testosterone-3-C14 was administered intraperitoneally to a male guinea pig and by the addition of suitable carrier steroids to the urinary extracts, several metabolities of testosterone have been demonstrated. experimental 6 mg. (1.2×106 cts./min./mg.)2 of testosterone -3-C14 prepared by the method of Turner (1950) were administered in corn oil to an 800 gm. male guinea pig.

Urinary oestrogens in the buffalo as measured chemically.

Abstract: A KNOWLEDGE of the level and the rate at which hormones are excreted is of considerable academic value for diagnostic and therapeutic purposes. The determination of œstrogen activity in the excreta is limited by the fact that these hormones are eliminated from the body in biologically active and inactive forms, thus necessitating chemical methods of measurement. The present work, consisting of two experiments, was carried out to ascertain the level and the rate at which urinary œstrogens are excreted in the buffalo and their chemical form.