Ovulatory response, ovarian LH/hCG receptors and serum concentrations of LH, insulin and steroid hormones in immature Zucker rats after PMSG treatment

The objective of present work is to estimated peripheral blood serum concentrations of pregnancyhormones, oestradiol , progesterone and testosterone , in cows . For this purpose 24 Frezain- Holsteincows at different stages of pregnancy the blood samples were taken from jugular veins. The serumwere separated and frozen at – 20 c until analysis. The serum hormones were measured by a specificELISA technique (ELISA Linear Multi Reader). The data were represented Mean + S.D. Progesteronewas high during pregnancy reaching a maximum of 91.94 + 26.09 ng/ml during last thirds (6-8months) of pregnancy , but was below 9.12 + 2.41 ng/ml for several months during the pregnancy.Oestradiol levels varied from 9.0+ 2.89 pg/ml in the first thirds of pregnancy to 282.6 + 48 .514 pg/mlduring the last month of gestation. While testosterone hormone level was low 0.32 + 0.12 ng /mlduring pregnancy. The result indicated that the major sources of hormones appeared to be the 0vary(corpus luteum ) and the uterus (placenta). The ovarian contribution was greater during the first – thirdsof pregnancy than later, whereas that made by the placenta was higher during the last thirds ofpregnancy

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Serum concentrations of reproductively-related circulating steroid hormones in the free-ranging lemon shark, Negaprion brevirostris

The reproduction and development of sharks, skates, rays and ratfishes - Developments in environmental biology of fishes ◽

10.1007/978-94-017-3450-9_15 ◽

1993 ◽

pp. 167-174 ◽

Cited By ~ 2

Author(s):

Lois E. L. Rasmussen ◽

Samuel H. Gruber

Keyword(s):

Steroid Hormones ◽

Serum Concentrations ◽

Lemon Shark ◽

Negaprion Brevirostris ◽

Free Ranging

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Long-term studies of Serum Concentrations of reproductively related Steriod Hormones in individual captive Carcharhinids

Marine and Freshwater Research ◽

10.1071/mf9920273 ◽

1992 ◽

Vol 43 (1) ◽

pp. 273 ◽

Cited By ~ 26

Author(s):

LEL Rasmussen ◽

FL Murru

Keyword(s):

Steroid Hormones ◽

Mature Female ◽

Serum Concentrations ◽

Carcharhinus Plumbeus ◽

Short Term ◽

Serum Samples ◽

Negaprion Brevirostris ◽

Serial Serum ◽

Long Term Studies

Valuable information on maturity and reproductive status can be obtained by the measurement of the concentrations of steroid hormones in the serum of captive carcharhinid sharks. The sharks at Sea World of Florida, Orlando, Florida, include mature females of several species of placental sharks. Serial serum samples from four mature female Carcharhinus plumbeus, one maturing female C. leucas, and one mature and one nearly mature female Negaprion brevirostris were used to determine serum concentrations of 17�-oestradiol, progesterone, testosterone and dihydrotestosterone. The data from these mature placental sharks were then compared with concentrations measured in immature female and male conspecifics and in mature female Eugomphodus taurus (family Odontaspididae). Evidence of repetitive cyclical patterns was obtained from a mature female N. brevirostris. This shark was monitored from June 1988 to July 1990 by means of more than 50 samples that were often obtained at weekly intervals. Concentrations of 17�-oestradiol in the serum of this shark varied in a cyclical fashion, with the highest values obtained in Year 1 (1988-89) being during April (the normal mating season) and those in Year 2 (1989-90) being during June. Concomitant elevations of testosterone concentrations were observed either simultaneously or immediately before or after maximal oestradiol concentrations were noted. Progesterone concentrations were low except for definitive spikes that immediately preceded the maximal concentrations of testosterone and 17�-oestradiol. These periodicities suggest, for placental sharks, that consistently rising oestradiol concentrations may set in motion preovulatory events, that testosterone may be important for the initiation of subsequent ovulatory events, and that transitory elevations of progesterone concentrations may have specific short-term roles. These cyclical changes in the concentrations of steroid hormones observed in captive elasmobranchs support observations of hormone concentrations during reproduction in wild carcharhinids.

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Serum profiles of steroid hormones in patients with Cushing's syndrome determined by a new HPLC/RIA method

Clinical Chemistry ◽

10.1093/clinchem/37.8.1329 ◽

1991 ◽

Vol 37 (8) ◽

pp. 1329-1333 ◽

Cited By ~ 25

Author(s):

H Ueshiba ◽

M Segawa ◽

T Hayashi ◽

Y Miyachi ◽

M Irie

Keyword(s):

Steroid Hormones ◽

Cushing’S Syndrome ◽

High Performance ◽

Adrenal Adenoma ◽

Cushing's Syndrome ◽

Serum Concentrations ◽

Adrenal Hyperplasia ◽

Steroid Profile ◽

17 Hydroxyprogesterone ◽

Normal Adults

Abstract We developed a method for simultaneously measuring steroid hormones in very small volumes of serum, using a combination of high-performance liquid chromatography (HPLC) and radioimmunoassay (RIA). By this method, aldosterone, cortisol, 11-deoxycortisol, estrone, estradiol, androstenedione, dehydroepiandrosterone, deoxycorticosterone, 17-hydroxyprogesterone, testosterone, pregnenolone, and progesterone could be determined in a single 100-microL aliquot of serum from normal adults and patients with Cushing's syndrome. The steroid profile associated with Cushing's syndrome caused by adrenal adenoma was quite distinct from that associated with the syndrome caused by adrenal hyperplasia. Serum concentrations of androstenedione, dehydroepiandrosterone, estrone, estradiol, 17-hydroxyprogesterone, pregnenolone, and testosterone were significantly higher in patients with adrenal hyperplasia than in those with an adenoma. We compared the results of this HPLC/RIA method with those of 125I RIAs. The use of a HPLC/RIA system to obtain an accurate and sensitive profile of a range of serum steroids, as described here, obviates the need for large volumes of blood.

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