INFLUENCE OF OOPHORECTOMY, LUTEECTOMY, FOETAL DEATH AND DEXAMETHASONE ON THE PERIPHERAL PLASMA LEVELS OF OESTROGENS AND PROGESTERONE IN THE PREGNANT MACACA MULATTA

1974 ◽  
Vol 75 (3) ◽  
pp. 601-616 ◽  
Author(s):  
W. T. K. Bosu ◽  
E. D. B. Johansson ◽  
C. Gemzell

ABSTRACT The influence of bilateral oophorectomy, luteectomy, dexamethasone injections and foetal death on the peripheral plasma levels of oestrogens1) and progesterone was studied in pregnant rhesus monkeys. After bilateral oophorectomy and luteectomy, pregnancy proceeded normally and the plasma levels of oestrogens and progesterone attained levels similar to those in intact monkeys, but the progesterone levels after parturition were comparatively lower. Dexamethasone injections into pregnant monkeys had no deleterious effect on the outcome of gestation. Abrupt and dramatic decreases in total oestrogens, oestrone and oestradiol levels occurred during dexamethasone injections into intact and oophorectomized pregnant monkeys but no significant changes in progesterone levels in plasma were observed. Spontaneous intra-uterine foetal death was accompanied by decrease in oestrogens, but no changes in the plasma levels of progesterone. In experimentally induced foetal death, the oestrogen and progesterone levels in plasma decreased prior to abortion. These data demonstrate the relative influence of the ovaries, adrenals and the placenta on the maternal plasma levels of oestrogens and progesterone in the pregnant rhesus monkey.

1979 ◽  
Vol 81 (3) ◽  
pp. 345-349 ◽  
Author(s):  
J. S. ROBINSON ◽  
R. NATALE ◽  
L. CLOVER ◽  
M. D. MITCHELL

The concentrations of prostaglandin E (PGE), thromboxane B2 (TXB2) and 6-oxo-prostaglandin F1α (6-oxo-PGF1α) were measured by radioimmunoassay in serial samples of amniotic fluid and maternal peripheral plasma in the latter third of pregnancy in rhesus monkeys (Macaca mulatta). The samples were collected under ketamine-induced anaesthesia. The concentration of PGE was undetectable in amniotic fluid until a few days before delivery when a large increase was observed in three of the five animals. There were small increases of TXB2 and 6-oxo-PGF1α in amniotic fluid before delivery. In maternal plasma the concentrations of PGE, TXB2 and 6-oxo-PGF1α were generally higher and more variable than in amniotic fluid and did not increase with advancing gestation. It is suggested that increased production of primary prostaglandins occurs before, and is involved in, the onset of parturition in the rhesus monkey.


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.


1973 ◽  
Vol 74 (4) ◽  
pp. 743-755 ◽  
Author(s):  
William T. K. Bosu ◽  
Elof D. B. Johansson ◽  
Carl Gemzell

ABSTRACT The maternal peripheral plasma levels of oestrone (E1)*, oestradiol-17β (E2) and progesterone (P) were determined by RIA during pregnancy in 8 rhesus monkeys (Macaca mulatta). Of special interest were the time courses and the inter-relationships of these steroids during the first month of pregnancy and during the pre- and post-parturient periods. A significant increase in the plasma levels of E1 and E2 occurred at the end of the fertile cycle and lasted for several days and again during the last week before parturition. The plasma levels of E1 and E2 fell dramatically after parturition and remained low during the immediate post-partum period. Two surges in the progesterone levels in plasma occurred at the end of the third week of the fertile cycle and between day 34 and 46 after the onset of menstruation. The progesterone levels in plasma during the remaining gestational period varied widely but a significant increase was found during the days before parturition. A decrease in the plasma levels of P was observed after parturition but the levels of P did not reach follicular phase levels during the post-partum period studied. The possibility of oestrogen secretion from follicles stimulated by chorionic gonadotrophins is discussed as well as the release of prostaglandins by oestrogen before parturition.


1977 ◽  
Vol 73 (2) ◽  
pp. 355-363 ◽  
Author(s):  
J. R. G. CHALLIS ◽  
PHILLIDA HARTLEY ◽  
P. JOHNSON ◽  
J. E. PATRICK ◽  
J. S. ROBINSON ◽  
...  

SUMMARY Representative C21, C19 and C18 steroids have been measured in the amniotic fluid and maternal femoral plasma of rhesus monkeys during the last 50 days of pregnancy. The concentrations of cortisol, progesterone, androstenedione, oestrone and oestrone sulphate all increased in amniotic fluid before spontaneous parturition. In contrast, amniotic fluid oestradiol levels remained low and unchanged, and were always less than the concentrations in the maternal plasma. The changes in progesterone, cortisol and oestrone concentrations in amniotic fluid occurred independently of significant changes in the concentration of these steroids in the maternal plasma. Betamethasone administered to monkeys after day 150 of pregnancy suppressed amniotic fluid and maternal plasma cortisol. This treatment markedly suppressed the concentration of progesterone in amniotic fluid, but did not alter its concentration in maternal plasma. It is concluded that during late pregnancy in the rhesus monkey there is an increase in the concentration of some steroids in amniotic fluid independent of alterations in their concentrations in maternal plasma. These changes could reflect an increase in foetal adrenal steroid secretion.


1973 ◽  
Vol 74 (2) ◽  
pp. 348-360 ◽  
Author(s):  
William T. K. Bosu ◽  
Elof D. B. Johansson ◽  
Carl Gemzell

ABSTRACT Peripheral plasma levels of oestrogens1), progesterone and 17α-hydroxyprogesterone were measured during normal pregnancy in seven rhesus monkeys. The plasma concentrations of oestrogens ranged between 200 and 1300 pg/ml throughout the gestation period. Increases in the levels of oestrogens in plasma occurred several days before parturition. The plasma concentrations of progesterone ranged between 0.5 and 22 ng/ml during pregnancy. The concentrations of oestrogens decreased dramatically after parturition and remained low during the post-partum period. The concentration of progesterone decreased after parturition, but did not reach follicular phase levels during the period observed. The plasma levels of 17α-hydroxyprogesterone were low throughout the gestation period and during the post-partum period.


1980 ◽  
Vol 84 (3) ◽  
pp. 489-494 ◽  
Author(s):  
G. JENKIN ◽  
M. D. MITCHELL ◽  
P. HOPKINS ◽  
C. D. MATTHEWS ◽  
G. D. THORBURN

A radioimmunoassay for the determination of concentrations of melatonin in the plasma of rhesus monkeys has been developed. Antiserum for the assay was raised against N-acetyl serotonin and there was a 100% cross-reaction with melatonin. Cross-reactivity with closely related indoles, precursors and metabolites was less than or equal to 1%. The lower limit of sensitivity of the assay was 4 pg/tube. The assay has been used for the investigation of diurnal variations and cyclical changes in melatonin concentrations in peripheral plasma of the rhesus monkey. The concentrations of melatonin ranged between 26·6 and 85·3 pg/ml during sampling for 24 h.There was a distinct diurnal variation in the concentration of melatonin in plasma. The concentration during darkness (61·0 ± 7·1 (s.e.m.) pg/ml) was greater (P <0·01) than that during illumination (40·1 ± 6·1 pg/ml). There were no significant differences in the concentration of melatonin in plasma at any time during the 28 day menstrual cycle of the rhesus monkey.


1974 ◽  
Vol 63 (1) ◽  
pp. 125-135 ◽  
Author(s):  
RICHARD BARANCZUK ◽  
G. S. GREENWALD

SUMMARY Oestrone (OE1), oestradiol (OE2) and progesterone were measured by radioimmunoassay in the same samples of peripheral plasma from pregnant and lactating hamsters. The levels of progesterone during most of pregnancy did not exceed the values found during the first 2 days of the oestrous cycle. However, on day 14 of pregnancy (2 days before parturition) the level of progesterone abruptly increased to 29 ng/ml and fell rapidly thereafter. Hysterectomy on day 12 of pregnancy resulted in baseline levels of progesterone ( < 2 ng/ml) on day 13 and no peak in progesterone comparable to the one observed on day 14 of normal gestation. Injecting progesterone on day 14 or later prolonged gestation and caused maternal and foetal death. Oestradiol concentration showed peaks on days 7 (67·3 pg/ml), 11 (117·6 pg/ml) and 14 (81·8 pg/ml) of pregnancy and dropped precipitously between days 14 and 16 of pregnancy. The highest values obtained on day 11 correlated with the maximal proliferation of antral follicles. The abrupt decline of oestrogen concentration at parturition is different from the pattern found in the mouse and rat but is consistent with the lack of post-partum ovulation in the hamster. Injecting 50–150 μg oestradiol cyclopentylpropionate between days 12 and 16 did not interfere with parturition by the morning of day 16. Oestrone was detectable throughout pregnancy; the levels were lower than for OE2. In general, the oestrogen patterns were parallel. During lactation, progesterone secretion remained relatively constant at about 10–11 ng/ml, presumably synthesized by the hypertrophied interstitium which is the dominant ovarian tissue. In most instances OE1 and OE2 were not detectable during lactation, consistent with the absence of antral follicles.


2001 ◽  
Vol 69 (5) ◽  
pp. 3519-3522 ◽  
Author(s):  
Lori M. Hansen ◽  
Jay V. Solnick

ABSTRACT Helicobacter pylori strain J166 recovered from experimentally inoculated rhesus monkeys had up to a 250-fold-increased urease activity over that before inoculation. This was found to result from the selection of urease positive J166 clones from a heterogenous inoculum, which was predominantly urease negative due to a 1-bp insertion in the ureA gene. These results confirm the importance of urease for H. pylori colonization. Strain J166 is particularly well adapted to the rhesus monkey, since it colonized preferentially despite the fact that less than 0.1% of the inoculum was urease positive.


1951 ◽  
Vol 7 (2) ◽  
pp. 194-202 ◽  
Author(s):  
S. H. GREEN ◽  
S. ZUCKERMAN

Estimates have been made of the total number of oocytes in ovaries removed on different days of the menstrual cycle from twelve sexually mature rhesus monkeys. They have been analysed on two assumptions: (a) that no relation exists over the range of age studied between age and the number of oocytes present; and (b) that such a relation exists. The data were grouped in the following three temporal phases of the menstrual cycle: days 1–9, days 10–18, days 19–27. Statistical analysis failed to reveal any significant difference between the average total number of oocytes present at the beginning, the middle, or the end of the menstrual cycle.


2004 ◽  
Vol 183 (1) ◽  
pp. 61-68 ◽  
Author(s):  
S Ramaswamy ◽  
C R Pohl ◽  
G R Marshall ◽  
T M Plant

This study examined the ontogeny of the testicular testosterone response to precocious pulsatile LH stimulation in the juvenile rhesus monkey. LH stimulation was achieved with an i.v. infusion (one pulse every 3 h) of either single-chain human (sch)LH, administered alone or in combination with recombinant human (rh)FSH, or recombinant monkey (rm)LH in combination with rmFSH. Homologous gonadotropin treatment resulted in an adult profile of circulating mLH concentrations. The schLH infusions produced a similar pulsatile pattern in circulating LH with peak concentrations of approximately 5 IU/l. Although a robust testicular testosterone response was observed after 24 h of intermittent LH stimulation, surprisingly testosterone release at this time was continuous. The apulsatile mode of testosterone secretion, however, did not persist, and a switch to an unequivocal episodic mode of secretion, comparable to that observed in adult monkeys, occurred by day 4 of LH stimulation. FSH did not influence the pattern of the testosterone response. We conclude from these findings that progenitor Leydig cells in the primate testis are able to respond rapidly to a physiological LH stimulus. While the cell biology underlying the switch from a continuous to a pulsatile mode of testosterone secretion remains unclear, we suggest that this phenomenon may be related to the hypothesis that episodic testosterone secretion is required for the operation of the neuroendocrine axis governing testicular function.


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