The Direct Luteotropic Effect of Tokishakuyakusan in Rats

1991 ◽  
Vol 19 (02) ◽  
pp. 163-169 ◽  
Author(s):  
Satoshi Usuki
Keyword(s):  
Corpus Luteum ◽  
Secretion Rate ◽  
Apparent Change ◽  
Progesterone Secretion ◽  
Cervical Stimulation ◽  
Venous Plasma

The effect of Tokishakuyakusan (TS) on the corpus luteum function in pseudopregnant rats was examined in vivo. On day 4 of pseudopregnancy (PSP), induced by cervical stimulation, TS (20 μg) stimulated the progesterone secretion rate (PSR) in the ovarian venous plasma. There was also a significant increase in the rate of progesterone to 20 α-OH-progesterone. However, on day 8 of PSP, there was no apparent change in PSR in the ovarian venous plasma after the administration of TS. These data suggest that the sensitivity to TS of the corpus luteum varies according to its age.

Adrenocortical metabolism of angiotensin in sheep with adrenal transplants.

1978 ◽  
Vol 235 (5) ◽  
pp. E525
Author(s):  
S Lun ◽  
E A Espiner ◽  
D S Hart
Keyword(s):  
Blood Flow ◽  
Adrenal Gland ◽  
Secretion Rate ◽  
Aldosterone Secretion ◽  
Adrenal Tissue ◽  
Rate Analysis ◽  
Venous Plasma

Conscious trained sheep with adrenal gland autotransplants in cervical skin loops were used to study adrenocortical metabolism and clearance of angiotensin (AII) administered by constant systemic infusion. For comparative purposes similar experiments were undertaken in five control sheep with skin loops but no cervical adrenal tissue. During AII infusions (0.33 microgram/min for 30 min), loop venous-arterial AII ratios (0.42--0.62 were similar in both groups of sheep. Measured AII clearances across the skin loop in sheep with and without adrenal transplants were 400--600 and 100--150 pg/min, respectively, which correlated with blood flow (r = 0.79), but showed no relation to aldosterone secretion rate. Analysis of AII immunoreactive fragments showed similar proportions of octa-, hepta-, and hexapeptide fractions (64, 26, and 5%, respectively) in adrenal arterial, adrenal venous, and systemic venous plasma. These studies do not support selective heptapeptide uptake or metabolism by adrenal tissue in vivo and indicate that specific adrenal binding of AII is likely to be less than 400 pg/min at arterial AII concentrations approximating 120 pg/ml.

Source of ovarian inhibin secretion during the oestrous cycle of the sheep

1989 ◽  
Vol 123 (2) ◽  
pp. 181-188 ◽  
Author(s):  
G. E. Mann ◽  
A. S. McNeilly ◽  
D. T. Baird
Keyword(s):  
Corpus Luteum ◽  
Luteal Phase ◽  
Venous Blood ◽  
Contralateral Side ◽  
Follicular Phase ◽  
Oestrous Cycle ◽  
Secretion Rate ◽  
Antral Follicles ◽  
Luteal Tissue

ABSTRACT The source of inhibin secretion by the ovary in the sheep at different stages of the oestrous cycle was investigated by in-vivo cannulation of the ovarian veins. Twenty-four Scottish Blackface ewes were allocated to four groups of six ewes, i.e. those operated on during the luteal phase (day 10), and those operated on during the follicular phase 24–30, 36 and 60 h following an injection of 125 μg cloprostenol on day 10 of the luteal phase. Samples of jugular and timed ovarian venous blood were collected under anaesthesia before and after enucleation of the corpus luteum. Ovaries were then removed and follicles dissected out. Following injection of cloprostenol, luteal regression occurred as indicated by a fall in the secretion of progesterone. The concentration of inhibin in jugular venous plasma and its ovarian secretion rate were similar at all stages of the follicular phase and during the luteal phase. In contrast, the secretion rate of oestradiol rose from 2·68 ±0·73 pmol/min during the luteal phase to 8·70± 2·24 pmol/min 24 h after injection of cloprostenol (P<0·05). Following enucleation of the corpus luteum the secretion rate of progesterone fell from 809 ± 270 pmol/min to 86 ± 30 pmol/min (P<0·001). There was also a smaller, artifactual fall in the secretion rate of oestradiol following enucleation of the corpus luteum, which was of similar size to a fall seen in the secretion rate of inhibin. This resulted in a significant (P<0·001) fall in the ratio of progesterone to inhibin, while the oestradiol to inhibin ratio remained unchanged. The secretion rate of inhibin from ovaries containing luteal tissue was similar to that from the contralateral side without luteal tissue (1·41±0·30 compared with 1·32±0·30 ng/min), while ovaries with large antral follicles secreted significantly (P< 0·001) more inhibin than those with no follicles ≥3 mm (2·28 ± 0·36 compared with 0·25 ±0·06 ng/min). From these results we conclude that, in the sheep, large antral follicles are responsible for most, if not all, the secretion of inhibin by the ovary at all stages of the oestrous cycle, and that the corpus luteum secretes little or no immunoactive or bioactive inhibin. Due to the fact that, unlike inhibin, the secretion rate of oestradiol rises during the follicular phase of the cycle, when the concentration of FSH is suppressed, it seems likely that oestradiol rather than inhibin is the major ovarian factor modulating the change in FSH secretion seen at this stage of the oestrous cycle. Journal of Endocrinology (1989) 123, 181–188

EFFECTS OF HUMAN CHORIONIC GONADOTROPHIN ON THE RELEASE OF CYCLIC AMP AND PROGESTERONE FROM THE SHEEP OVARY AT DIFFERENT STAGES OF THE OESTROUS CYCLE

1978 ◽  
Vol 89 (1) ◽  
pp. 158-165 ◽  
Author(s):  
T. J. Weiss ◽  
P. O. Janson ◽  
K. J. Porter ◽  
R. F. Seamark
Keyword(s):  
Cyclic Amp ◽  
Corpus Luteum ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Oestrous Cycle ◽  
Secretion Rate ◽  
Arterial Plasma ◽  
Venous Plasma

ABSTRACT The rate of release of cyclic AMP by sheep ovaries containing a corpus luteum was determined at different stages of the cycle before and up to 60 min after an intra-arterial (ia) injection of 500 IU human chorionic gonadotrophin (hCG). The median cyclic AMP concentration in arterial plasma and of ovarian venous plasma following hCG stimulation was 93.2 and 98.0 pmol/ml, respectively. The ovaries of ewes examined at Days 1 and 2 of the cycle showed no response to hCG, whereas in 2 sheep at Day 3, hCG caused a slight response, and in 13 sheep examined between Days 5–18, hCG caused a marked increase in cAMP release. In 5 of the sheep in which both ovarian veins were cannulated, only the ovary with a corpus luteum responded to hCG with an increased secretion rate of cyclic AMP and progesterone. The results indicate a lack of responsiveness in the newly formed corpus luteum to hCG.

scholarly journals Real-time dynamics of prostaglandin F2α release from uterus and corpus luteum during spontaneous luteolysis in the cow

Reproduction ◽  
2004 ◽  
Vol 128 (2) ◽  
pp. 189-195 ◽  
Author(s):  
Koumei Shirasuna ◽  
Hitomi Asaoka ◽  
Tomas J Acosta ◽  
Missaka P B Wijayagunawardane ◽  
Masayuki Ohtani ◽  
...  
Keyword(s):  
Corpus Luteum ◽  
Real Time ◽  
Prostaglandin F2α ◽  
Paracrine Factor ◽  
Time Dynamics ◽  
Physiological Relevance ◽  
A Site ◽  
Local Release ◽  
Venous Plasma

Prostaglandin (PG) F2α released from the uterus in a pulsatile fashion is essential to induce regression of the corpus luteum (CL) in the cow. In addition to the uterus, the CL has also been recognized as a site of PGF2α production. Therefore, this study aimed to determine the detailed dynamics of the releasing profile of CL-derived PGF2α together with uterus-derived PGF2α during spontaneous luteolysis in the cow. Non-lactating Holstein cows (n = 6) were surgically implanted with a microdialysis system (MDS) on day 15 (oestrus = day 0) of the oestrous cycle. Simultaneously, catheters were implanted to collect ovarian venous plasma ipsilateral to the CL as well as jugular venous plasma. The concentrations of PGF2α, 13,14-dihydro-15-keto-PGF2α (PGFM) and progesterone in the MDS and plasma samples were determined by enzyme immunoassays. The intra-luteal PGF2α secretion slightly increased after the onset of luteolysis (0 h) and drastically increased from 24 h, and was maintained at high levels towards the following oestrus. Furthermore, PGF2α was released from the CL into the ovarian vein in a pulsatile manner during spontaneous luteolysis. Also, the fact that intra-luteal secretion of PGF2α and PGFM showed a positive correlation indicates the existence of a local metabolic pathway for PGF2α in the CL. In conclusion, the present study clarified the real-time dynamics of uterus-derived PGF2α and CL-derived PGF2α during spontaneous luteolysis in the cow, and gives the first in vivo evidence that the CL releases PGF2α during spontaneous luteolysis in the cow. Although the physiological relevance of CL-derived PGF2α appears to be restricted to a local role as an autocrine/paracrine factor in the CL, overall results support the concept that the local release of PGF2α within the regressing CL amplifies the luteolytic action of PGF2α from the uterus.

Local production of progesterone by the corpus luteum of the marmoset monkey in response to perfusion with chorionic gonadotrophin and melatonin in vivo

1987 ◽  
Vol 112 (3) ◽  
pp. 449-457 ◽  
Author(s):  
G. E. Webley ◽  
J. P. Hearn
Keyword(s):  
Corpus Luteum ◽  
Positive Control ◽  
Chorionic Gonadotrophin ◽  
Test Material ◽  
Corpora Lutea ◽  
Local Production ◽  
Progesterone Secretion ◽  
Stimulation Of

ABSTRACT The effect of human chorionic gonadotrophin (hCG) and melatonin on the local production of progesterone by the marmoset corpus luteum was investigated in vivo using a perfusion cannula system. Progesterone secretion was measured in 10-min fractions of buffer which had been perfused through the corpus luteum at a flow rate of 70 μl/min for a maximum of 3 h in anaesthetized animals. Two corpora lutea were cannulated in each animal; one for perfusion of test material and the other for perfusion with buffer alone as a control. Perfusion with hCG (25 i.u./ml), investigated as a positive control, produced a marked stimulation of progesterone secretion which increased 10–20 min from the start of perfusion and reached a peak after 30–60 min. A stimulation of progesterone was also observed after perfusion with melatonin (860 pmol/l). The response was evident within 10–30 min of the hormone reaching the corpus luteum and was similar in magnitude to that observed for hCG. The ability of melatonin to stimulate progesterone secretion supports previous in-vitro studies and suggests an ovarian action for melatonin in the primate. The local perfusion system described may have potential uses in studies of luteal function related to aspects of infertility or regulation of fertility. J. Endocr. (1987) 112, 449–457

THE IN-VIVO EFFECTS OF SHEEP PITUITARY GONADOTROPHINS ON THE SECRETION OF STEROIDS BY THE AUTOTRANSPLANTED OVARY OF THE EWE

1969 ◽  
Vol 45 (3) ◽  
pp. 425-440 ◽  
Author(s):  
J. A. McCRACKEN ◽  
A. UNO ◽  
J. R. GODING ◽  
Y. ICHIKAWA ◽  
D. T. BAIRD
Keyword(s):  
Blood Flow ◽  
Secretion Rate ◽  
Steroid Secretion ◽  
Progesterone Secretion ◽  
Ovine Prolactin ◽  
In Vivo Effects ◽  
Measurable Change ◽  
Ovarian Cycles

SUMMARY The transplanted ovary preparation in the ewe permits long-term access to both the arterial and venous sides of the ovarian circulation in the unstressed, unanaesthetized animal. However, these animals are not completely normal, as the separation of the ovary from the uterus results in ovarian cycles with a prolonged luteal phase and the infrequent manifestation of behavioural oestrus. Treatment with exogenous gonadotrophins made it possible to carry out direct infusion experiments on the transplanted ovary on a more uniform basis. The effect on ovarian blood flow and on ovarian steroid secretion following the infusion of ovine luteinizing hormone (LH), ovine follicle-stimulating hormone (FSH) or ovine prolactin directly into the arterial supply of the transplanted ovary of the ewe is described. Four infusions of each of the three ovine pituitary gonadotrophins were made into the ovary at rates varying from 0·1 μg./hr. to 1000 μg./hr. LH infusions produced an increase in both ovarian blood flow and steroid secretion at all dosage levels employed. Androstenedione showed the greatest increase (600%) in secretion rate after LH, followed by testosterone (400%), oestradiol (more than 50%) and progesterone (less than 50%). Progesterone however showed the greatest increase in terms of mass of steroid secreted. There was no measurable change in the secretion of oestrone. Ovarian blood flow increased by at least 20% (range 20–125%) within 1 hr. of beginning the LH infusion. On the other hand FSH and prolactin infused at the same or at a higher rate than LH, had essentially no effect on ovarian blood flow or steroid secretion rate. In two out of four FSH infusions there appeared to be a transient fall in progesterone secretion rate. The infusion of 0·9% NaCl solution into the ovary as a control had no effect on blood flow or on steroid secretion.

PROGESTERONE SECRETION BY THE SHEEP CORPUS LUTEUM AFTER REPEATED INFUSIONS OF LUTEINIZING HORMONE AND HUMAN CHORIONIC GONADOTROPHIN

1973 ◽  
Vol 57 (2) ◽  
pp. 299-305 ◽  
Author(s):  
D. T. BAIRD ◽  
R. A. COLLETT
Keyword(s):  
Luteinizing Hormone ◽  
Corpus Luteum ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Constant Infusion ◽  
Temporary Increase ◽  
Ovarian Artery ◽  
Progesterone Secretion ◽  
Luteal Tissue

SUMMARY The response of the ovine corpus luteum to repeated infusions of luteinizing hormone (LH) or of human chorionic gonadotrophin (HCG) was tested in four ewes with the left ovary autotransplanted to the neck. Constant infusion for 1 h of either LH (100 or 1000 μg/h) or HCG (200 i.u./h) via the ovarian artery stimulated a temporary increase in secretion of progesterone which fell to control levels by 60 min. Ovarian blood flow increased progressively (P < 0·05) throughout the infusion of gonadotrophin in three of the five experiments. A second infusion of either gonadotrophin after a further control hour failed to stimulate progesterone secretion. These results suggest that ovine luteal tissue rapidly becomes refractory to the steroidogenic effect of LH in vivo.

Regulation of the corpus luteum of early pregnancy in the marmoset monkey: local interactions of luteotrophic and luteolytic hormones in vivo and their effects on the secretion of progesterone

1987 ◽  
Vol 114 (2) ◽  
pp. 231-239 ◽  
Author(s):  
J. P. Hearn ◽  
G. E. Webley
Keyword(s):  
Corpus Luteum ◽  
Early Pregnancy ◽  
Local Level ◽  
Corpora Lutea ◽  
Progesterone Production ◽  
Marmoset Monkey ◽  
Progesterone Secretion ◽  
Late Luteal Phase ◽  
Prostaglandin F

ABSTRACT The interaction between luteotrophic and luteolytic agents in controlling progesterone production by the marmoset corpus luteum in the late luteal phase/early pregnancy was investigated at the local level in vivo using a perfusion cannula system. Perfusion of the prostaglandin F2α(PGF2α) analogue, cloprostenol (0·5 μg/ml), resulted in an immediate fall in progesterone production. This response was not sustained in two out of five corpora lutea but pregnancy was terminated in all animals exposed to PGF2α. Perfusion of human chorionic gonadotrophin (hCG) (4 μg/ml) alone significantly stimulated progesterone secretion but there was no response to hCG when the corpus luteum had previously been perfused with PGF2α. Perfusion with hCG together with PGF2α prevented a fall in progesterone secretion. The results suggest that the luteolytic action of PGF2α in the marmoset may be to prevent luteotrophic support of the corpus luteum. Melatonin (860 pmol/l), perfused either with PGF2α or after PGF2α, stimulated progesterone production. The ability of melatonin to influence progesterone production by the primate corpus luteum may therefore be by both a direct luteotrophic action and the prevention of luteolysis. Application of the perfusion system in order to investigate the ability of deglycosylated hCG to antagonize the action of hCG at the corpus luteum showed the necessity of testing pure preparations of hormones. J. Endocr. (1987) 114, 231–239

PROGESTERONE IN THE HUMAN PERIPHERAL BLOOD IN THE PREOVULATORY PERIOD OF THE MENSTRUAL CYCLE

1967 ◽  
Vol 55 (1) ◽  
pp. 91-96 ◽  
Author(s):  
Benno Runnebaum ◽  
Josef Zander
Keyword(s):  
Menstrual Cycle ◽  
Corpus Luteum ◽  
Peripheral Blood ◽  
Human Peripheral Blood ◽  
Progesterone Concentration ◽  
Plasma Progesterone ◽  
Progesterone Secretion ◽  
Graafian Follicle ◽  
The Mean ◽  
Mean Concentration

ABSTRACT Progesterone was determined and identified in human peripheral blood during the preovulatory period of the menstrual cycle, by combined isotope derivative and recrystallization analysis. The mean concentration of progesterone in 1.095 ml of plasma obtained 9 days before ovulation was 0.084 μg/100 ml. However, the mean concentration of progesterone in 1.122 ml of plasma obtained 4 days before ovulation was 0.279 μg/100 ml. These data demonstrate a source of progesterone secretion other than the corpus luteum. The higher plasma-progesterone concentration 4 days before ovulation may indicate progesterone secretion of the ripening Graafian follicle of the ovary.

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