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Showing papers on "Steroid biosynthesis published in 1970"


Journal ArticleDOI
TL;DR: Results clearly show that the atretio follicle of the Guppy does not produce steroid hormones, and it is preferable to use the name Corpus atreticum instead of Corpus luteum praeovulationis.

84 citations



Journal ArticleDOI
TL;DR: In vitro steroid biosynthesis in the 700 g supernatant fraction of the male-phase ovotestis of Ariolimax californicus was investigated and it was shown that the following sequence occurred in male- phases: Cholesterol → pregnenolone → 17a-hydroxypregnenolones → dehydroepiandrosterone → androstenedione.

49 citations


Journal ArticleDOI
TL;DR: Pathways leading from pregnenolone to androstenedione (the delta-4, and the delta-5 pathways) similar to those operating in the mammalian ovary, have been demonstrated to operate in the ovary of Tilapia.

38 citations


Journal ArticleDOI
24 Apr 1970-Science
TL;DR: In cultures of mouse adrenocortical tumor cells (Sato's minimal deviation Y-1 clonal strain), the acceleration of steroid biosynthesis after exposure to Adrenocorticotropic hormone or cyclic adenosine 3',5'-monophosphate is maximum within 15 to 60 minutes and precedes any significant increase in labeling of protein with [4,5-3H]leucine.
Abstract: In cultures of mouse adrenocortical tumor cells (Sato9s minimal deviation Y-1 clonal strain), the acceleration of steroid biosynthesis after exposure to adrenocorticotropic hormone or cyclic adenosine 39,59-monophosphate is maximum within 15 to 60 minutes and precedes any significant increase in labeling of protein with [4,5- 3 H]leucine. However, when cytosol proteins are separated by acrylamidegel electrophoresis, rapid changes in the amount and labeling of several protein fractions are evident in less than 30 minutes and are no longer evident within 60 minutes. This finding supports the proposal that the effects of tropic hormones and their intracellular mediators involve rapid selective effects on protein synthesis.

27 citations


Journal ArticleDOI
TL;DR: The enzyme activities of the submicrosomal fraction which were diminished by the gradient centrifugation were largely restored by addition of the heated 105,000 × g supernatant fluid.

26 citations


Journal ArticleDOI
TL;DR: The “primary interstitial gland” of juvenile rabbit ovaries is of epithelial origin, derived from the medullary cords and the granulosal nests, although the “secondary interstitial glands” is considered to arise from the theca interna of atretic follicles.
Abstract: Ovaries from rabbits one to three months old were examined to demonstrate the histogenesis of ovarian interstitial cells. Electron micrographs showed that “primary interstitial gland cells” with abundant agranular endoplasmic reticulum were present prior to appearance of follicular atresia and that extensive development of the agranular endoplasmic reticulum and accumulation of lipid droplets occurred in the epithelial cells of medullary cords and granulosal cell nests. Therefore, it was concluded that the “primary interstitial gland” of juvenile rabbit ovaries is of epithelial origin, derived from the medullary cords and the granulosal nests, although the “secondary interstitial gland” is considered to arise from the theca interna of atretic follicles. This conclusion was confirmed by biochemical and histochemical demonstration of 3β-hydroxysteroid dehydrogenase, an enzyme system necessary for steroid biosynthesis. The activity of 3β-hydroxysteroid dehydrogenase increased significantly at two months when the agranular reticulum began to devlop in epithelial cells. Histochemical findings showed that the cells having the enzyme activity were consistent with the cells containing a large quantity of lipid.

23 citations


Journal ArticleDOI
TL;DR: DHA and DHA sulphate were produced mainly by the reticular tissue and there was a marked stimulation of their synthesis in this tissue under the influence of ACTH.

20 citations




Journal Article
TL;DR: The environmental persistence of chlorinated hydrocarbon insecticides is posing a serious threat to the survival of several wildlife species and to possible adverse effects on perinatal and adult individuals.
Abstract: The environmental persistence of chlorinated hydrocarbon insecticides is posing a serious threat to the survival of several wildlife species. Sublethal effects, completely unrelated to the insecticidal properties of these chemicals, have contributed markedly to impaired reproduction in many species and to toxicity in neonatal animals. Considering the insecticide levels found in man, are these chemicals potentially dangerous to human infants and adults? Of special concern are the potential long-term, subtle effects of low concentrations of insecticides to which many persons are ordinarily exposed. These agents affect both the peripheral and central nervous systems. They markedly elevate hepatic enzyme levels, enhancing the biotransformation of many pharmacological agents as well as interfering with endogenous steroid biosynthesis and degradation. The DDT-like insecticides are potent estrogenic agents and some have shown teratogenic and carcinogenic activity. These aspects are discussed in relation to present levels found in humans and to possible adverse effects on perinatal and adult individuals.


Book ChapterDOI
01 Jan 1970
TL;DR: The present investigation was carried out to test the effect of a human FSH preparation on males with infertility of varying pathogenesis and to seek criteria for grouping infertile patients in relation to response to therapy.
Abstract: Although human follicle-stimulating hormone (FSH) has been demonstrated to be effective in the initiation or restoration of human spermatogenesis (1), its use in the treatment of male infertility has had variable results (2). Various reports indicate that FSH has no effect on steroid biosynthesis in the testis (3,4) while others suggest a stimulating effect on testosterone and estrogen production (5). The present investigation was carried out to test the effect of a human FSH preparation on males with infertility of varying pathogenesis. In addition to following the response of the sperm count, the study included assay of pituitary and gonadal hormones in blood and urine and investigation of bio-synthetic pathways in small amounts of testicular tissue obtained at biopsy. Criteria were sought for grouping infertile patients in relation to response to therapy.

Journal ArticleDOI
TL;DR: Normal ovarian tissue from cycle day 7 was minced and incubated with isomolar quantities of labelled pregnenolone and progesterone with and without the addition of cofactors to enhance the activity of 3β-01 dehydrogenase, 17-hydroxylase,17-ketosteroid reductase, and aromatizing activity, while they did not appear to affect desmolase significantly.

Journal ArticleDOI
TL;DR: The large amounts of urinary estriol excreted by the pregnant woman during late pregnancy are derived from the fetus and the placenta functioning as an integrated biosynthetic unit, and can serve as an indicator of the adequacy of fetal steroid biosynthesis and metabolism.

Journal ArticleDOI
TL;DR: The effects of SU-4885 on the rat adrenal cortex by oral administration of 50mg/kg, single or daily for 10 days, were morphologically studied particularly with histochemical methods for the enzyme and lipid to indicate that the administration inhibits some decrease in the steroid biosynthesis from cholesterol possibly through the ‘short route’.
Abstract: The effects of SU-4885 on the rat adrenal cortex by oral administration of 50mg/kg, single or daily for 10 days, were morphologically studied particularly with histochemical methods for the enzyme and lipid Lipid depletion with fragmentation of droplets throughout the zona fasciculata in rats with single administration conformed to the pattern of adreno-cortical response to an acute moderate stimulus Reduced activity of secondary alcohol dehydrogenase, fragmentation of lipid droplets, and acidophilic and trabecular changes in the cell cords were observed in the inner fasciculata following a single or daily administration for 10 days The medication apparently brought about hypersecretion of adrenocortical steroids, which was similar to the effect of ACTH administration Reduced activity of secondary alcohol dehydrogenase, which reflected the transformation of cholesterol in the steroid biosynthesis, was always observed in the zona fasciculata following the administration of SU-4885 or ACTH The result might indicate that the administration inhibits some decrease in the steroid biosynthesis from cholesterol possibly through the ‘short route’

Journal Article
TL;DR: Dual-labeled conversion products showed variations in their 3H:14C ratios which may be attributed to heterogeneity of the tumor cell population and their differences in activities of steroid-transforming enzymes.
Abstract: Summary Steroid biosynthesis was studied in a spontaneous mouse interstitial cell tumor grown as a transplant in isologous male recipients. In timed incubations the tumor tissue rapidly transformed dehydroepiandrosterone to androstenedione. The formation of testosterone, 11β-hydroxyandrostenedione, and 11β-hydroxytestosterone proceeded at a slower rate. A conversion product with chromatographic characteristics of 19-hydroxyandrostenedione was also found. Incubation of tumor tissue with equal weights of 3H-labeled pregnenolone and 14C-labeled progesterone resulted in formation of dual-labeled progesterone, 17α-hydroxyprogesterone, androstenedione, testosterone, 11-deoxycorticosterone, corticosterone, and 20α-hydroxypregn-4-en-3-one. A dual-labeled compound with characteristics of 11β-hydroxyprogesterone was also detected. The tumor tissue in its steroid biosynthetic properties partly resembled testis tissue and partly resembled adrenocortical tissue. Dual-labeled conversion products showed variations in their 3H:14C ratios which may be attributed to heterogeneity of the tumor cell population and their differences in activities of steroid-transforming enzymes.