CONVERSION OF LABELLED CHOLESTEROL TO NEUTRAL STEROIDS BY HUMAN OVARIES PERFUSED IN VIVO

1974 ◽  
Vol 75 (2) ◽  
pp. 368-378
Author(s):  
S. Dell'Acqua ◽  
S. Mancuso ◽  
M. G. Catelli ◽  
A. Bompiani
Keyword(s):  
Luteal Phase ◽  
Ovarian Tissue ◽  
Venous Blood ◽  
The Other ◽  
Ovarian Artery ◽  
The Third ◽  
Human Ovaries

ABSTRACT Four human ovaries in mid-luteal phase have been perfused with tritium labelled cholesterol through the cannulated ovarian artery for thirty minutes. Three 15-min samples of ovarian venous blood have been collected, two during the perfusion and the third in the following 15 min. In two cases, 15 min after the beginning of the perfusion, highly purified human urinary LH was rapidly injected into the ovarian artery. The ovarian tissue and the three fractions of venous blood were analysed for phenolic and neutral steroids. In the ovarian tissue only progesterone (4-pregnene-3,20-dione), pregnenolone (3β-hydroxy-5-pregnen-20-one) and 17α-hydroxyprogesterone (17α-hydroxy-4-pregnene-3,20-dione) were isolated. The amount of progesterone isolated from the two ovaries injected with LH was five times higher as compared with the other two ovaries. No steroids were present in the samples of venous blood except in the two cases in which LH was injected, where progesterone was isolated only in the third sample. It is concluded that circulating cholesterol is utilized by the ovary at the mid-luteal phase for the synthesis of C21 steroids and that the presence of LH increases the production and the release of progesterone by the ovary.

THE FORMATION OF OESTROGENS BY THE AUTOTRANSPLANTED OVARY OF THE EWE PERFUSED IN VIVO WITH C19 STEROIDS

1970 ◽  
Vol 65 (2) ◽  
pp. 244-260 ◽  
Author(s):  
Andre Rado ◽  
John A. McCracken ◽  
David T. Baird
Keyword(s):  
Steady State ◽  
Luteinizing Hormone ◽  
Venous Blood ◽  
The Other ◽  
Temporary Increase ◽  
Main Route ◽  
Ovarian Artery ◽  
Constant Rate ◽  
Control Samples

ABSTRACT The autotransplanted ovary of the ewe was perfused in vivo via the ovarian artery with either 14C or 3H labelled C19 steroids. 17β-Oestradiol was the major phenolic steroid isolated in ovarian venous blood from either testosterone or androstenedione. Smaller amounts of oestrone were obtained but there was no 17α-oestradiol, oestriol nor conjugated oestrogens isolated. The yield of oestrogen was approximately ten fold greater from androstenedione than from testosterone suggesting that the main route of oestrogen biosynthesis in the ovine ovary is via the former steroid. The effect of infusing luteinizing hormone (LH) at the rate of 10 μg per hour on the conversion of androstenedione to 17β-oestradiol was measured in 5 experiments. In 2 experiments, when the steady state was not achieved, the increasing rate of conversion was halted. On the other hand LH resulted in a temporary increase followed by a decrease in the rate of conversion in the remaining 3 experiments in which there was a constant rate of conversion in the control samples. These results are compatible with the concept that LH stimulates the aromatisation of androstenedione to oestrogens by the ovary in vivo.

Comparative rates of formation, in vivo, of 16-androstenes, testosterone and androstenedione in boar testis

1984 ◽  
Vol 103 (2) ◽  
pp. 179-186 ◽  
Author(s):  
E. L. Hurden ◽  
D. B. Gower ◽  
F. A. Harrison
Keyword(s):  
Binding Sites ◽  
Venous Blood ◽  
Peripheral Circulation ◽  
Total Radioactivity ◽  
Venous Blood Flow ◽  
Large White ◽  
The Third ◽  
Very High ◽  
Venous Plasma

ABSTRACT Three mature Large White boars were anaesthetized and received [7(n)-3H]pregnenolone by continuous infusion into right and left spermatic arteries for up to 180 min. Spermatic venous blood flow was measured by separate timed collections of completely diverted outflow from each testis and blood not sampled was returned to the peripheral circulation. The total radioactivity in plasma from each testis increased markedly during the first 60 min of infusion to reach a plateau from 80 to 180 min. Radiolabelling of 5α-androst-16-en-3-one, 5α-androst-16-en-3β-ol and -3α-ol showed similar patterns with ratios of mean radioactivity of 5:3:1 respectively between 80 and 180 min. In comparison, the amounts of tritiated 4,16-androstadien-3-one formed were very small. The radiolabelling of testosterone and 4-androstenedione occurred more rapidly than that of the 16-androstenes and reached maxima by 30 min. However the amounts were only one-fifth (testosterone) and one-tenth (4-androstenedione) those of the combined quantities of tritiated 16-androstenes. Addition of human chorionic gonadotrophin (hCG) to the infusate to one testis in each animal (so that 5000 i.u. hCG were delivered in 15–20 min) produced no change in the outputs of radiolabelled steroids although radioimmunoassay of spermatic venous plasma in samples from the third experiment showed a transient increase in the concentration of 4-androstene-3,17-dione during the hCG infusion. It is suggested the lack of response to hCG could be produced by saturation and down regulation of binding sites by the very high local concentrations of hCG. J. Endocr. (1984) 103, 179–186

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

THE EFFECT OF BLOOD-BORNE FACTORS ON ADRENAL STEROID SYNTHESIS IN THE GOLDEN HAMSTER (MESOCRICETUS AURATUS NEHRING)

1967 ◽  
Vol 37 (2) ◽  
pp. 139-146 ◽  
Author(s):  
BARBARA J. WHITEHOUSE ◽  
G. P. VINSON ◽  
P. A. JANSSENS
Keyword(s):  
Enzyme Activity ◽  
Golden Hamster ◽  
Venous Blood ◽  
Ringer Solution ◽  
The Other ◽  
Steroid Synthesis ◽  
Adrenal Steroid ◽  
Adrenal Tissue ◽  
Rapid Conversion

SUMMARY Incubation of hamster adrenal tissue in Krebs bicarbonate Ringer solution gave rapid conversion of added [4-14C]cortisol to cortisone. Moreover, incubation in Ringer solution with [4-14C]progesterone as precursor invariably yielded cortisone in greater amounts than cortisol. On the other hand it has been confirmed that cortisol is the major free ultraviolet absorbing steroid in the adrenal venous blood of the hamster. Incubation of adrenal tissue with [4-14C]progesterone in hamster whole blood gave relatively greater amounts of cortisol which were more in keeping with the findings in vivo. This suggested that the blood contains factors which affect the cortisone-cortisol equilibrium by modifying adrenal enzyme activity. Some reduction of [3H] cortisone to cortisol was also observed during incubation with blood alone.

EFFECTS OF PITUITARY HORMONES ON PROGESTATIONAL HORMONE PRODUCTION BY THE RABBIT OVARY IN VIVO AND IN VITRO

1966 ◽  
Vol 35 (1) ◽  
pp. 53-63 ◽  
Author(s):  
J. H. DORRINGTON ◽  
R. KILPATRICK
Keyword(s):  
Ovarian Tissue ◽  
Venous Blood ◽  
Interstitial Tissue ◽  
Corpora Lutea ◽  
Hormone Production ◽  
Stimulatory Action ◽  
Steroid Synthesis ◽  
Ovine Prolactin

SUMMARY Ovine luteinizing hormone (LH) increased the output of progestational steroids (20α-hydroxypregn-4-en-3-one and progesterone) in rabbit ovarian venous blood. Similar increases were found with ovine follicle-stimulating hormone (FSH) and growth hormone, but much larger amounts were necessary. Ovine prolactin was without effect. The increased output was due to increased synthesis and not only to release of stored steroids. Synthesis of these progestational steroids was stimulated by LH incubated with rabbit ovarian tissue. The stimulation produced by FSH was probably due to contamination by LH since the log dose-response lines for LH and FSH were parallel, and FSH was approximately 100 times less active than LH. Ovine prolactin had no stimulatory activity in concentrations up to 20 μg./ml. The stimulatory action of LH was unrelated to the presence of corpora lutea. Separated corpora lutea showed only a slight response to LH, whereas the response of interstitial tissue was similar to that found with undissected ovaries. Hence LH caused progestational steroid synthesis by stimulating the ovarian interstitial tissue.

STEROIDOGENIC EFFECTS OF LUTEINIZING HORMONE AND PROLACTIN ON THE RAT OVARY IN VIVO

1967 ◽  
Vol 38 (4) ◽  
pp. 423-430 ◽  
Author(s):  
K. YOSHINAGA ◽  
SUSAN A. GRIEVES ◽  
R. V. SHORT
Keyword(s):  
Luteinizing Hormone ◽  
Venous Blood ◽  
The Other ◽  
Progesterone Secretion ◽  
Rat Ovary

SUMMARY Progesterone and 20α-dihydroprogesterone were measured in the ovarian venous blood of rats in early pro-oestrus, late dioestrus, day 5 of pseudopregnancy, and in androgen-treated animals with persistent oestrus. Little progesterone was secreted in early pro-oestrus or persistent oestrus (0·1 μg./hr.), but the secretion rose in dioestrus (2·1 μg./hr.) and in pseudopregnancy (7 μg./hr.). The 20α-dihydroprogesterone secretion was low in the persistent oestrous group; in all the other groups it was 1·5–3 μg./hr. Treatment with luteinizing hormone increased progesterone secretion within 30 min. in pro-oestrus and persistent oestrus, had no significant effect in dioestrus, and depressed it markedly in pseudopregnancy. It appeared to have no significant effect on 20α-dihydroprogesterone secretion except during pseudopregnancy, when it was depressed. Treatment with prolactin produced no effect within 30 min.in pro-oestrous, dioestrous or pseudopregnant animals.

Enhancement of ADP-induced Platelet Aggregation by Adrenaline in Vivo and Its Prevention

1973 ◽  
Vol 29 (02) ◽  
pp. 490-498 ◽  
Author(s):  
Hiroh Yamazaki ◽  
Itsuro Kobayashi ◽  
Tadahiro Sano ◽  
Takio Shimamoto
Keyword(s):  
Platelet Count ◽  
Platelet Aggregation ◽  
Platelet Rich Plasma ◽  
The Other ◽  
Endothelial Surface ◽  
Important Interaction ◽  
Blood Coagulability ◽  
The Difference

SummaryThe authors previously reported a transient decrease in adhesive platelet count and an enhancement of blood coagulability after administration of a small amount of adrenaline (0.1-1 µg per Kg, i. v.) in man and rabbit. In such circumstances, the sensitivity of platelets to aggregation induced by ADP was studied by an optical density method. Five minutes after i. v. injection of 1 µg per Kg of adrenaline in 10 rabbits, intensity of platelet aggregation increased to 115.1 ± 4.9% (mean ± S. E.) by 10∼5 molar, 121.8 ± 7.8% by 3 × 10-6 molar and 129.4 ± 12.8% of the value before the injection by 10”6 molar ADP. The difference was statistically significant (P<0.01-0.05). The above change was not observed in each group of rabbits injected with saline, 1 µg per Kg of 1-noradrenaline or 0.1 and 10 µg per Kg of adrenaline. Also, it was prevented by oral administration of 10 mg per Kg of phenoxybenzamine or propranolol or aspirin or pyridinolcarbamate 3 hours before the challenge. On the other hand, the enhancement of ADP-induced platelet aggregation was not observed in vitro, when 10-5 or 3 × 10-6 molar and 129.4 ± 12.8% of the value before 10∼6 molar ADP was added to citrated platelet rich plasma (CPRP) of rabbit after incubation at 37°C for 30 second with 0.01, 0.1, 1, 10 or 100 µg per ml of adrenaline or noradrenaline. These results suggest an important interaction between endothelial surface and platelets in connection with the enhancement of ADP-induced platelet aggregation by adrenaline in vivo.

The Spectrum of von Willebrand’s Disease

1967 ◽  
Vol 18 (01/02) ◽  
pp. 040-056 ◽  
Author(s):  
E. J Walter Bowie ◽  
P Didisheim ◽  
J. H Thompson ◽  
C. A Owen
Keyword(s):  
Factor Viii ◽  
Bleeding Time ◽  
Severe Bleeding ◽  
Platelet Adhesiveness ◽  
Platelet Activity ◽  
Von Willebrand's Disease ◽  
Von Willebrand’S Disease ◽  
The Third ◽  
Generation Test

SummaryPatients (from 5 kindreds) with variants of von Willebrand’s disease are described. In one kindred the depression of factor VIII was moderate (20 to 40% of normal) and transfusion of 500 ml of normal plasma led to an increase higher than anticipated and to an almost normal level of factor VIII 17 to 24 hrs later. This represents the usual type of von Willebrand’s disease.In the second kindred the concentration of factor VIII was less than 2 % of normal in the son and daughter, who had severe bleeding and hemarthroses.The third kindred was characterized by reduction of factor VIII and a long bleeding time as well as by a serum defect in the thromboplastin-generation test comparable to that seen in patients with hemophilia B, yet with normal levels of factors IX, X, and VII. The severity of the serum defect, the positive result with the Rumpel-Leede test, and the reduced platelet activity in the thromboplastin-generation test are all compatible with the diagnosis of thrombopathy or ‘‘thrombopathic hemophilia.” In two other kindreds, one patient had a long bleeding time and normal levels of factor VIII and another had a normal bleeding time and decrease of factor VIII. The last patient had the type of response to transfusion usually seen in von Willebrand’s disease.In four kindreds, platelet adhesiveness in vivo was found to be strikingly abnormal (virtually absent).It would appear, therefore, that von Willebrand’s disease forms a spectrum, and whether the kindreds reported simply reflect variations of a single genetic disease state or represent separate entities will be answered only by clarification of the underlying etiology of that disease.

Efficacy of some insecticide modules against major insect pests and spider population of rice, Oryza sativa L.

ENTOMON ◽  
2018 ◽  
Vol 43 (4) ◽  
pp. 257-262
Author(s):  
Atanu Seni ◽  
Bhimasen Naik
Keyword(s):  
Oryza Sativa ◽  
Grain Yield ◽  
Untreated Control ◽  
Insect Pests ◽  
Oryza Sativa L ◽  
Gall Midge ◽  
Stem Borer ◽  
The Other ◽  
The Third ◽  
Treated Plot

Experiments were carried out to assess some insecticide modules against major insect pests of rice. Each module consists of a basal application of carbofuran 3G @ 1 kg a.i ha-1 at 20 DAT and Rynaxypyr 20 SC @ 30 g a.i ha-1 at 45 DAT except untreated control. All modules differ with each other only in third treatment which was applied in 65 DAT. The third treatment includes: Imidacloprid 17.8 SL @ 27 g a.i ha-1, Pymetrozine 50 WG @ 150 g a.i ha-1, Triflumezopyrim 106 SC @ 27 g a.i ha-1, Buprofezin 25 SC @ 250 g a.i ha-1; Glamore (Imidacloprid 40+Ethiprole 40% w/w) 80 WG @ 100 g a.i. ha-1, Thiacloprid 24 SC @ 60 g a.i ha-1, Azadirachtin 0.03 EC @ 8 g a.i ha-1, Dinotefuran 20 SG@ 40 g a.i ha-1 and untreated control. All the treated plots recorded significantly lower percent of dead heart, white ear- head caused by stem borer and silver shoot caused by gall midge. Module with Pymetrozine 50 WG @ 150 g a.i ha-1 treated plot recorded significantly higher per cent reduction of plant hoppers (>80% over untreated control) and produced higher grain yield (50.75 qha-1) than the other modules. Among the different treated modules the maximum number of spiders was found in Azadirachtin 0.03 EC @ 8 g a.i ha-1 treated module plot followed by other treatments.

Аpplying of high-frequency monopolar diathermocoagulation in the treatment of chronic pulpitis

2020 ◽  
Vol 1 (12) ◽  
pp. 40-42
Author(s):  
F. Yu. Daurova ◽  
D. I. Tomaeva ◽  
S. V. Podkopaeva ◽  
Yu. A. Taptun
Keyword(s):  
Root Canal ◽  
High Frequency ◽  
Antibacterial Effect ◽  
Comparison Group ◽  
Poor Quality ◽  
Endodontic Treatment ◽  
Root Canals ◽  
The Third ◽  
Before And After

Relevance: the reason for the development of complications in endodontic treatment is poor-quality instrumental treatment root canals.Aims: a study of the animicrobial action and clinical efficacy of high-frequency monopolar diathermocoagulation in the treatment of chronic forms of pulpitis.Materials and methods: 102 patients with various chronic forms of pulpitis were divided into three groups of 34 patients each. In the first two groups, high-frequency monopolar diathermocoagulation was used in endodontic treatment in different modes. In the third group, endodontic treatment was carried out without the use of diathermocoagulation (comparison group). The root canal microflora in chronic pulpitis in vivo was studied twice-before and after diathermocoagulation.Results: it was established that high-frequency monopolar diathermocoagulation in the effect mode is 3, power is 4 (4.1 W) and effect is 4, power is 4 (5.4 W) with an exposure time of 3 seconds, it has a pronounced antibacterial effect on all presented pathogenic microflora obtained from the root canals of the teeth.

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