Concentrations of total and free dehydroepiandrosterone in plasma and dehydroepiandrosterone in saliva of normal and hirsute women under basal conditions and during administration of dexamethasone/synthetic corticotropin

1990 ◽  
Vol 36 (12) ◽  
pp. 2042-2046 ◽  
Author(s):  
L M Swinkels ◽  
H A Ross ◽  
A G Smals ◽  
T J Benraad

Abstract Using a specific and sensitive radioimmunoassay involving extraction with diethyl ether and chromatographic separation of steroids, we measured concentrations of salivary and plasma dehydroepiandrosterone (DHEA) in 22 women with normal ovulatory cycles (ages 18-45 years). Salivary DHEA values closely correlated with total and free DHEA in plasma. In the follicular phase the mean concentrations of salivary and plasma free DHEA were virtually equal [mean (SD): 0.61 (0.32) and 0.56 (0.34) nmol/L, respectively]. In the luteal phase, salivary DHEA slightly exceeded the plasma free DHEA [0.68 (0.40) vs 0.56 (0.38) nmol/L, P less than 0.01]. Also, during combined dexamethasone/synthetic corticotropin administration in 25 patients with androgenizing disorders and in 10 normal subjects (each in the follicular and luteal phases), the concentration of DHEA in saliva strongly correlated with total and free DHEA in plasma. During these dynamic tests, the mean concentrations of free DHEA in plasma and salivary DHEA in the hirsute women were significantly higher than the mean concentrations in the control women at all times before and after corticotropin infusion (P less than 0.05- less than 0.0001). In contrast, plasma total DHEA in patients exceeded nonhirsute values only at 15 min after corticotropin administration. In six of 25 patients total DHEA during combined administration of dexamethasone/synthetic corticotropin exceeded normal values by at least 2 SD. The response of salivary and free DHEA to synthetic corticotropin in this subgroup was also excessive.

1980 ◽  
Vol 26 (3) ◽  
pp. 429-432
Author(s):  
P S Verma ◽  
P E Lorenz ◽  
G E Sander

Abstract A greatly simplified radioimmunoassay for bradykinin in human plasma is described. Current techniques require multiple chromatographic steps or extraction procedures with analytical recoveries of bradykinin of often less than 60%. We present a method in which bradykinin is separated from components of higher relative molecular mass (including kininogens) in a single step, by use of a column of Sephadex G-25 medium (PD-10). The mean analytical recovery of tritiated bradykinin added to plasma is 85.5% (SD, 3.5%). The sensitivity of this radioimmunoassay is 25 pg per assay tube, equivalent to 125 ng per liter of plasma. Twenty to 30 blood samples may be completely processed and assayed within 6 h. As determined with this technique, concentrations of bradykinin in plasma from apparently normal subjects ranged from 2.5 to 5.2 microgram/L (mean 4.2, SD 1.1 microgram/L); these values are consistent with previously reported normal values.


Reproduction ◽  
2002 ◽  
pp. 509-513 ◽  
Author(s):  
DC Skinner ◽  
SD Cilliers ◽  
JD Skinner

Springbok are aseasonally breeding wild ungulates that inhabit arid environments, and interest has been shown in domesticating them for agricultural purposes. The present study was conducted for husbandry purposes to determine the effect of introducing a vasectomized ram to an isolated herd of springbok ewes (n = 9). Blood was collected from ewes every third day, before and after introduction of a vasectomized ram. Ewes were subjected to the ram for 42 days. Plasma progesterone was measured by radioimmunoassay and was used to establish the stage of the oestrous cycle. After introduction of the ram, the variation in the timing of the follicular phase between ewes was clearly reduced, compressing the spread of oestrus in the springbok ewes from 11 to 3 days. In seven of the nine ewes, the ram was introduced during the luteal phase of the oestrous cycle, causing this cycle to be significantly longer in duration (P < 0.05) and to have a higher maximum concentration of progesterone (P < 0.001) than cycles before and after introduction of the ram. This finding implies that the mechanism of synchronization operates through a luteotrophic effect. These results indicate that rams may be used successfully to synchronize breeding in springbok.


1976 ◽  
Vol 83 (4) ◽  
pp. 684-691 ◽  
Author(s):  
Sven Johan Nillius ◽  
Leif Wide

ABSTRACT Modulating effects of oestradiol-17β and progesterone on the pituitary responsiveness to luteinizing hormone-releasing hormone (LRH) were investigated in 12 women with functional amenorrhoea. The pituitary reserve capacity for gonadotrophin section was investigated with repeated intravenous LRH tests before and after administration of oestradiol-1β followed by either progesterone or saline. Intramuscular injection of 1 mg of oestradiol-17β benzoate resulted in a suppression of both the basal gonadotrophin levels in serum and the gonadotrophin responses to LRH 24 h later. Progesterone, 25 mg im, was then administered in eleven experiments. Six h later, when the mean serum progesterone level had increased to levels similar to those seen in the early post-ovulatory phase of the menstrual cycle, there was a marked augmentation of the pituitary capacity to release both luteinizing hormone (LH) and follicle-stimulating hormone (FSH) in response to LRH. This was not found in eight experiments where saline was given instead of progesterone after oestrogen pretreatment. These findings suggest that the greatly increased pituitary sensitivity to LRH at midcycle may be caused not only by the oestradiol increase in blood during the late follicular phase but also in part by the small pre-ovulatory rise of progesterone during the mid-cyclic LH peak. Furthermore, they add further support to the hypothesis that progesterone as well as oestradiol is involved in the induction of the LH peak at midcycle. Progesterone may be of importance to secure the release of enough LH for ovulation and normal corpus luteum formation to occur.


1982 ◽  
Vol 62 (6) ◽  
pp. 581-588 ◽  
Author(s):  
Massimo Volpe ◽  
Bruno Trimarcoy ◽  
Bruno Ricciardelli ◽  
Carlo Vigorito ◽  
Nicola De Luca ◽  
...  

1. The effects of intravenous administration of neostigmine and propranolol, individually or in combination, on baroreflex responsiveness have been evaluated in 18 borderline hypertensive subjects and in 14 age-matched control subjects. 2. Baroreceptor sensitivity was tested by evaluating both heart rate response to phenylephrine-induced increase in arterial pressure, and heart rate and blood pressure changes induced by increasing neck-tissue pressure by means of a neck-chamber. 3. In borderline hypertensive subjects a reduced baroreflex responsiveness was demonstrated with both stimuli as compared with normal subjects. Neostigmine administration improved consistently both reflex responses. Similarly, after propranolol treatment, borderline hypertensive subjects showed a significant enhancement of the baroreflex sensitivity. Finally, the combined administration of neostigmine and propranolol restored the baroreflex responses. In fact, both the mean slopes of the regression lines between blood pressure and R-R interval after phenylephrine and the increase in mean arterial pressure and heart rate induced by the reduction in carotid transmural pressure in borderline hypertensive subjects were similar to those observed in normals. 4. These findings indicate that in borderline hypertensive subjects the impairment of baroreflex responsiveness is mainly due to abnormalities of autonomic regulation.


1976 ◽  
Vol 81 (2) ◽  
pp. 351-361 ◽  
Author(s):  
Maria Eugenia Escobar ◽  
Marco A. Rivarola ◽  
César Bergadá

ABSTRACT Plasma Oe2 concentration was measured by radioimmunoassay in patients with premature thelarche, with precocious puberty and in 29 normal controls. The mean plasma Oe2 was 1.5 pg/ml (0–7.2) in normal prepubertal girls, 23.8 ± 17.8 (sd) in pubertal girls, 50.2 (± 19.4) in the follicular phase, and 94.2 (± 19.5) in the luteal phase of normal adult females. Ten girls with premature thelarche had a mean of 7.7 ± 6.6 pg/ml. Three of them showed higher values than the other 7, suggesting that in these cases, elevated levels of plasma Oe2 might have played a role in the development of breast tissue. Ten untreated girls with idiopathic precocious sexual development had a mean of 51.6 ± 42.9 pg/ml while 6 patients treated with 150 mg per week of medroxyprogesterone acetate had a mean of 11.4 ± 2.5 pg/ml. Two patients with Down's syndrome, hypothyroidism and sexual precocity had plasma Oe2 of 144 and 31.5 which fell to 24.7 and 8 pg/ml, respectively, after thyroid replacement. One girl with a granulosa cell tumour had a basal value of 304 pg/ml and a concentration of 27 pg/ml after surgery.


1980 ◽  
Vol 26 (3) ◽  
pp. 429-432 ◽  
Author(s):  
P S Verma ◽  
P E Lorenz ◽  
G E Sander

Abstract A greatly simplified radioimmunoassay for bradykinin in human plasma is described. Current techniques require multiple chromatographic steps or extraction procedures with analytical recoveries of bradykinin of often less than 60%. We present a method in which bradykinin is separated from components of higher relative molecular mass (including kininogens) in a single step, by use of a column of Sephadex G-25 medium (PD-10). The mean analytical recovery of tritiated bradykinin added to plasma is 85.5% (SD, 3.5%). The sensitivity of this radioimmunoassay is 25 pg per assay tube, equivalent to 125 ng per liter of plasma. Twenty to 30 blood samples may be completely processed and assayed within 6 h. As determined with this technique, concentrations of bradykinin in plasma from apparently normal subjects ranged from 2.5 to 5.2 microgram/L (mean 4.2, SD 1.1 microgram/L); these values are consistent with previously reported normal values.


1998 ◽  
Vol 156 (1) ◽  
pp. 91-98 ◽  
Author(s):  
L Riboni ◽  
C Escamilla ◽  
R Chavira ◽  
R Dominguez

The effects of peripheral sympathetic denervation induced by guanethidine administration to newborn and 10-day-old female guinea pigs on puberty, ovulation and the follicular population were analysed. Peripheral sympathetic denervation beginning at birth resulted in the loss of ovarian norepinephrine content (0.95. +/- 0.1 ng/mg wet tissue in untreated control animals vs non detectable in treated animals). Guanethidine administration to newborn or 10-day-old guinea pigs advanced puberty (age of vaginal opening: 27 +/- 1.2 days (newborn), 26 +/- 1.7 (10-day-old) vs 37 +/- 0.7 (control), P < 0.001) and ovulation. The number of corpora lutea in control and denervated animals was similar (3.5 +/- 0.2 vs 3.3 +/- 0.3). The relative weight (mg/100 g body weight) of the ovaries and adrenals in the denervated animals autopsied during the late follicular phase (24-48 h after vaginal opening) increased (ovaries: 27.8 +/- 1.3, 28.9 +/- 3.0 vs 20.9 +/- 0.8, P < 0.05; adrenals 36.4 +/- 1.4, 37.0 +/- 0.8 vs 31.6 +/- 1.5, P < 0.05), while the uterine weight diminished (179 +/- 13, 149 +/- 28 vs 292 +/- 20). When the animals were killed during the late luteal phase (9-11 days after vaginal closure), the relative weight of the ovaries of newborn guanethidine-treated animals was higher than that of the control animals (21.4 +/- 1.7 vs 16.8 +/- 1.4, P < 0.05). The mean number of follicles counted in the ovaries of denervated animals was significantly higher than in control animals (1736 +/- 230 vs 969 +/- 147, P < 0.05). The mean diameter of the follicles in the untouched control ovary in animals killed in the late follicular phase was significantly larger than from animals killed in the late luteal phase (263 +/- 3.9 microns vs 248 +/- 3.0 microns, P < 0.01). The mean diameter of the follicles measured in the ovaries of denervated animals was significantly higher than in controls (animals treated from birth 274 +/- 2.0 microns vs 255 +/- 2.4, P < 0.05; animals treated from day 10, 286 +/- 2.3 microns vs 257 +/- 2.3, P < 0.05). When the mean diameter of the follicles in the left and right ovary of the untouched control was analysed, the follicular diameter in the left ovary was significantly larger than in the right ovary (309 +/- 6.0 microns vs 214 +/- 3.9, P < 0.01); the response of the left and right ovaries to sympathetic denervation was the opposite. The results obtained in the present study suggest that ovarian innervation plays a role in the regulation of follicular growth, maturation and atresia which is not related to changes in steroid secretion by the ovary, but to other regulatory mechanisms.


1973 ◽  
Vol 74 (4) ◽  
pp. 732-742 ◽  
Author(s):  
William T. K. Bosu ◽  
Elof D. B. Johansson ◽  
Carl Gemzell

ABSTRACT The levels of oestrone (E1)*, oestradiol-17β (E2) and progesterone (P) were determined simultaneously by radioimmunoassay in serial peripheral plasma samples from 11 rhesus monkeys (Macaca mulatta) during ovulatory menstrual cycles. In 3 other monkeys luteectomy was performed on day 20 or 21 of the menstrual cycle. The mean plasma levels of oestradiol-17β predominated over the mean E1 during the follicular phase, but during the luteal phase the E1 and E2 patterns varied widely. Before menstruation, increased or unchanged levels of E1 and E2 were mostly found. The decrease found in a few monkeys never reached the low levels found during the days after the midcycle peak. The plasma levels of progesterone increased from less than 0.2 ng/ml during the follicular phase to maximal values within 3 to 4 days after the midcycle peak of oestradiol-17β. The plasma levels of progesterone decreased to less than 1 ng/ml and remained low for 3 to 5 days before menstruation. In the luteectomized monkeys the plasma levels of P, E1 and E2 fell dramatically within 24 h and vaginal bleeding was detected within 72 h post-operatively. In 2 of the 3 luteectomized monkeys the levels of E1 and E2 increased before the bleeding. The ratio of oestrogens (oestradiol-17β and oestrone) over progesterone changed markedly in favour of the oestrogens during the pre-menstrual period. It is concluded that the patterns of progesterone and oestrogens are divergent during the luteal phase. The maximal levels of progesterone are reached early while the maximal levels of oestrogens are reached later during the luteal phase.


1976 ◽  
Vol 51 (1) ◽  
pp. 53-58
Author(s):  
N. K. Burki ◽  
Mary C. Dent

1. In five subjects, ten consecutive forced expiratory spirograms were recorded on each of 6 different days and the total forced expiratory time (FET) on each spirogram was measured. The mean overall coefficient of variation of the FET was 11·3% and of the ratio forced vital capacity (FVC)/FET was 8%. 2. Twenty-two subjects with probable small (<2 mm diameter) airway dysfunction as manifested by a reduced (<75% predicted) maximum mid-expiratory flow (MMEF) in the middle 50% of the FVC with normal FVC and FEV1 (>80% predicted) were studied before and after bronchodilatation. There was no significant correlation between change in FET and change in MMEF (r = 0·36, P > 0·01), but between change in MMEF (ΔMMEF) and change in FVC/FET (ΔFVC/FET) there was a positive correlation (r = 0·78, P < 0·001). 3. In six of these twenty-two subjects, the ΔFVC/FET and ΔMMEF on bronchodilatation correlated well with the change in residual volume (ΔRV), but neither measurement correlated well with the change in the ‘closing volume' measurement expressed as the ratio of phase 4/VC(%). The ΔFET did not correlate well with either ΔRV or Δ[phase 4/VC(%)]. 4. In eighty-one selected normal subjects (FVC, FEV, and MMEF all >80% predicted) there was better correlation of age with the FVC/FET (r = −0·676) than with the FET (r = +0·43); both correlations were significant (P < 0·001). 5. These results do not support the use of the FET as a suitable test of small airway function; however, the mean flow rate expressed as FVC/FET may, in the presence of a normal FEV1/FVC ratio, be an adequate test of small airway function.


2021 ◽  
Vol 12 ◽  
Author(s):  
Maissa Kacem ◽  
Rihab Borji ◽  
Sonia Sahli ◽  
Haithem Rebai

This study explored the fatigue effect on postural control (PC) across menstrual cycle phases (MCPs) in female athletes. Isometric maximal voluntary contraction (IMVC), the center of pressure sway area (CoParea), CoP length in the medio-lateral (CoPLX) and antero-posterior (CoPLY) directions, and Y-balance test (YBT) were assessed before and after a fatiguing exercise during the follicular phase (FP), mid-luteal phase (LP), and premenstrual phase (PMP). Baseline normalized reach distances (NRDs) for the YBT were lower (p = 0.00) in the PMP compared to others MCPs, but the IMVC, CoParea, CoPLX, and CoPLY remained unchanged. After exercise, the IMVC and the NRD decrease was higher at PMP compared to FP (p = 0.00) and LP (p = 0.00). The CoParea, CoPLX, and CoPLY increase was higher in the PMP compared to FP (p = 0.00) and LP (p = 0.00). It was concluded that there is an accentuated PC impairment after exercise observed at PMP.


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