English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

In view of the indication that an ether extract of uterine flushings from the pig contained progestational activity (Challis, Haynes & Lamming, in preparation) as measured by bioassay (McGinty, Anderson & McCullough, 1939), an attempt has been made to isolate progesterone from the reproductive tract flushings of the guinea-pig. In these experiments, radioactive progesterone was infused intravenously until equilibrium had been established between the endogenous circulating progesterone and labelled steroid. In such steady state conditions, 3H-labelled progesterone would be distributed in the same way as endogenous hormone. Tritiated progesterone (8-5 Ci/mmol) was infused into the left jugular vein of non-pregnant guinea-pigs (Illingworth, Heap & Perry, unpublished). Isotopie equilibrium was established within 3 hr and samples were taken for the determination of blood radioactivity. Towards the end of the infusion (3^ hr), the reproductive tract was exposed by a mid-ventral incision and the left Fallopian tube was cannulated near the fimbrial end, using a nylon cannula ('Portex' FG 2) of outer diameter 0-63 mm. The opposite uterine horn was clamped off at the cervical end with 'mosquito' forceps and the lumen contents of the left horn were flushed into a test-tube with 10 ml 0-9% NaCl (1 ml/min) through a large (7 mm) glass collecting cannula tied into position immediately below the cervix. This procedure, rather than direct cannulation through the uterine wall, avoided contaminating the flushings with blood, but meant that the collected material was from the tubai, uterine and cervical regions of the tract. All samples were stored at —15° C until analysis. Non-radioactive carrier progesterone (100 µg) was dissolved in 0-2 ml ethanol and equilibrated with a known volume of flushings. Unconjugated steroids were extracted with diethyl ether (3 vol) and separated by thin-layer chromatography in the system, hexane : ethyl acetate, 2:1. The progesterone eluate was acetylated and rechromatographed in the system, benzene : ethyl acetate, 1:1. Aliquots from the progesterone area were taken for liquid scintillation counting and for gas chromatography of the free steroid by flame ionization detection (Heap, Holzbauer & Newport, 1966), or its heptafluorobutyrate ester (Challis & Heap, 1969) by electron capture detection. The remainder was converted to 20/?-dihydroprogesterone using the 20/?-hydroxysteroid dehydrogenase enzyme

THE IDENTIFICATION OF PROGESTERONE IN FLUSHINGS FROM THE REPRODUCTIVE TRACT OF NON-PREGNANT GUINEA-PIGS