SECRETION OF TESTOSTERONE BY THE EUTOPIC AND THE CRYPTORCHID TESTES IN THE SAME DOG

1966 ◽  
Vol 44 (4) ◽  
pp. 629-633 ◽  
Author(s):  
Kristen B. Eik-Nes
Keyword(s):  
Intravenous Administration ◽  
Venous Blood ◽  
Cryptorchid Testis ◽  
Secretion Rates

The concentration of testosterone has been measured in spermatic venous blood from eutopic and cryptorchid testes in the same anesthetized dog in experiments lasting for 90 minutes. Both testes secreted testosterone and increased production of the hormone following intravenous administration of gonadotrophin. The production of testosterone by the cryptorchid testis was, however, lower than that by the eutopic organ thus demonstrating that the condition of cryptorchism is associated with decreased secretion rates of testosterone in the canine.

Episodic ovarian inhibin secretion is not due to LH pulses in anoestrous ewes

1989 ◽  
Vol 123 (2) ◽  
pp. 173-179 ◽  
Author(s):  
B. K. Campbell ◽  
A. S. McNeilly ◽  
D. T. Baird
Keyword(s):  
Breeding Season ◽  
Plasma Levels ◽  
Single Injection ◽  
Venous Blood ◽  
Follicular Development ◽  
Blood Samples ◽  
A Site ◽  
Ovarian Inhibin ◽  
Secretion Rates

ABSTRACT In sheep, secretion of oestradiol by the ovary is stimulated by pulses of LH but the factors controlling ovarian inhibin secretion are not well understood. We have investigated the effect of a single injection of LH on the ovarian secretion of inhibin. Six anoestrous Finn–Merino ewes which had one ovary autotransplanted to a site in the neck had jugular and timed ovarian venous blood samples collected at 10-min intervals for a total of 5 h. The secretion rates of both inhibin (1–3 ng/min) and oestradiol (0·5–8 ng/min) were similar to those observed during the breeding season indicating significant follicular development in these animals. After injection of 2·5 μg NIH-LH-S25 intravenously the concentration of LH in plasma rose from a baseline of 1·8 ±0·1 (s.e.m.) μg/l to a peak of 3·9 ±0·3 μg/l (P<0·01). This LH pulse stimulated a corresponding increase (P<0·01) in oestradiol secretion from a basal level of 0·9±0·2 ng/min to a peak of 4·6±0·6 ng/min that occurred within 30 min of injection. Although inhibin secretion was episodic in nature, increases were not related to either exogenous or endogenous LH pulses. We conclude that, in contrast to oestradiol, the secretion of inhibin by the ovary is not controlled acutely by changes in plasma levels of LH during anoestrus. Journal of Endocrinology (1989) 123, 173–179

Transhepatic absorption and biliary excretion of insulin

1987 ◽  
Vol 65 (9) ◽  
pp. 1982-1987 ◽  
Author(s):  
Walter Zingg ◽  
Aron M. Rappaport ◽  
Bernard S. Leibel
Keyword(s):  
Intravenous Administration ◽  
Biliary Excretion ◽  
Venous Blood ◽  
Intraperitoneal Administration ◽  
Liver Cells ◽  
Insulin Concentration ◽  
Secretory Process ◽  
Insulin Administration ◽  
Hepatic Cells ◽  
Liver Surface

The application of insulin to the liver in rats is followed by an increase of the insulin concentration in the bile. The pathway of insulin from the liver surface to the bile may include a secretory process by the hepatic cells, or it may bypass the hepatic cells, using direct anatomical pathways from blood and lymph to bile. The concentration of insulin in arterial and venous blood, in lymph, and in bile was measured following application of insulin to the liver surface and following peritoneal or intravenous administration. The results confirm that insulin is absorbed from the surface of the liver, but the glucose modulating effect was less effective than after intravenous administration. The insulin concentration in bile was increased after insulin administration by all routes, with the highest and most prolonged increases found after intraperitoneal administration. The results suggest that following transhepatic and intravenous administration, insulin reaches the bile without passing through the liver cells.

Sulfobromophthalein inhibition of glutathione and methylmercury secretion into bile

1985 ◽  
Vol 248 (2) ◽  
pp. G238-G245 ◽  
Author(s):  
N. Ballatori ◽  
T. W. Clarkson
Keyword(s):  
Intravenous Administration ◽  
Transport Process ◽  
Biliary Secretion ◽  
Male Rats ◽  
Molar Ratio ◽  
Glutathione Disulfide ◽  
Direct Inhibition ◽  
Pentobarbital Sodium ◽  
Dose Dependent ◽  
Secretion Rates

The mechanism through which sulfobromophthalein (BSP) inhibits the biliary secretion of glutathione (GSH) and methylmercury was examined in male rats anesthetized with pentobarbital sodium. The biliary secretion rates of GSH and methylmercury were measured following the bolus intravenous administration of various doses of BSP, the GSH conjugate of BSP (BSP-SG), and phenol-3,6-dibromphthalein disulfonate (DBSP, a nonmetabolizable analogue of BSP). The effects of BSP on GSH secretion were dose dependent; at a dose of 120 mumol/kg the rate of GSH secretion fell close to zero. DBSP also inhibited GSH secretion, although the inhibition was not as complete as observed after BSP administration; at a dose of 180 mumol/kg GSH secretion fell to 18% of control. BSP-SG, in contrast, had no effect on GSH secretion into bile when given at a dose of 120 mumol/kg. At doses of 240 and 360 mumol BSP-SG/kg, there were only minor changes in the rate of GSH secretion. The changes in GSH secretion induced by these dyes were accompanied by proportional changes in glutathione disulfide (GSSG) secretion into bile, so that the molar ratio of GSSG to GSH in bile remained within the range of 0.07–0.18. In all experiments the changes in methylmercury secretion were parallel to the changes in GSH secretion. The results suggest that the BSP-induced inhibition of GSH, GSSG, and methylmercury secretion into bile is due to the direct inhibition of the biliary GSH transport process.

scholarly journals The Effect of Intravenous Histamine Administration on the Level of the White Blood Count in the Peripheral Blood

Blood ◽  
1951 ◽  
Vol 6 (10) ◽  
pp. 926-935 ◽  
Author(s):  
HOWARD R. BIERMAN ◽  
KEITH H. KELLY ◽  
NICHOLAS L. PETRAKIS ◽  
FAUNO CORDES ◽  
MARILEE FOSTER ◽  
...  
Keyword(s):  
Intravenous Administration ◽  
Peripheral Blood ◽  
Pulmonary Circulation ◽  
White Cell Count ◽  
Venous Blood ◽  
Peripheral Circulation ◽  
White Blood Count ◽  
Clotting Time ◽  
Arterial Blood ◽  
Leukocyte Number

Abstract 1. By simultaneously sampling venous and arterial blood by cardiac catheterization or vessel cannulation, the number of leukocytes entering and leaving the lungs was observed in 12 patients on 14 occasions. 2. The intravenous administration of histamine phosphate in doses of 0.1 to 0.3 mg. (as base) over 10 to 60 seconds, was accompanied by a prompt decrease in leukocyte number in the arterial blood 20 to 60 seconds before the venous white cell count fell. This was interpreted as demonstrating that the leukocytes were removed from tine peripheral blood in the pulmonary circulation. The granulocytic series appeared to be more involved in the leukopenia, although a similar but less apparent change was noted in the agranulocytes. 3. The leukopenia persisted for 40 to 180 seconds following which the arterial leukocyte count exceeded that in the venous blood indicating a return of leukocytes from the lungs into the peripheral circulation. 4. The intravenous administration of histamine also resulted in an immediate decrease in clotting time as determined both by glass and siliconed tube technics. 5. The intravenous injection of histamine affords a relatively simple technic to study one type of leukocyte removal mechanism present in the pulmonary circulation.

Ovarian secretion rates and peripheral concentrations of inhibin in normal and androstenedione-immune ewes with an autotransplanted ovary

1990 ◽  
Vol 127 (2) ◽  
pp. 285-296 ◽  
Author(s):  
B. K. Campbell ◽  
D. T. Baird ◽  
A. S. McNeilly ◽  
R. J. Scaramuzzi
Keyword(s):  
Luteal Phase ◽  
Venous Blood ◽  
Plasma Concentrations ◽  
Active Immunization ◽  
Follicular Phase ◽  
Secretion Rate ◽  
Luteal Function ◽  
Prostaglandin F ◽  
Ovarian Inhibin ◽  
Secretion Rates

ABSTRACT Active immunization of sheep against androstenedione results in an increase in ovulation rate that is associated with increased plasma levels of LH and progesterone, but not FSH. Although immunized ewes have more activated follicles the secretion rate of oestradiol is not increased. An experiment was conducted to examine the effect of androstenedione immunity on the ovarian secretion and peripheral plasma concentrations of inhibin. Merino ewes in which the left ovary had been autotransplanted to a site in the neck were divided into control (n = 5) and androstenedione-immune (n = 6) groups. Ovarian and jugular venous blood was collected every 10 min at two stages of the follicular phase, 21–27 h and 38–42 h after a luteolytic dose of an analogue of prostaglandin F2α (PG), and every 15 min for 6 h on day 10 of the subsequent luteal phase. The ewes were monitored regularly for luteal function by measurement of the concentration of progesterone and preovulatory LH surges. The concentration of inhibin in jugular and ovarian venous plasma was determined by radioimmunoassay and ovarian secretion rates and peripheral concentrations are expressed as pg of 1–26 peptide fragment of the α chain. The ovarian secretion rate of inhibin tended to be greater in androstenedione-immune ewes at all stages of the oestrous cycle measured, with this difference being statistically significant (P <0·05) during the luteal phase (100±40 and 260±80 (s.e.m.) pg/min for control and immune groups respectively). The pattern of ovarian inhibin secretion exhibited pulsatile-like fluctuations which were not associated with LH pulses. Peripheral concentrations of inhibin were generally higher in immunized than in control ewes with this difference being significant (P < 0·01) from day 4 to 14 of the luteal phase (59±5 and 110±7 ng/1 for control and immune respectively). The ovarian secretion rate of immunoactive inhibin was greater (P <0·01) during the follicular phase than during the luteal phase in both groups of ewes, and peripheral concentrations of inhibin increased (P < 0·001) following injection of PG in ewes from both treatment groups. We concluded that androstenedione immunity results in an increase in ovarian inhibin secretion, an effect that can probably be attributed to the greater number of large oestrogenic follicles present in the ovaries of these ewes. Furthermore, this increase in the concentration of inhibin may override any decrease in the negative feedback effects of ovarian steroid produced by immunization and, hence, explain the paradoxical findings of normal concentrations of FSH and raised concentrations of LH in ewes which are immunized against androstenedione. Journal of Endocrinology (1990) 127, 285–296

Adrenal of male dog secretes androgens and estrogens

1980 ◽  
Vol 239 (2) ◽  
pp. E109-E112
Author(s):  
R. J. Santen ◽  
E. Samojlik ◽  
L. Demers ◽  
E. Badder
Keyword(s):  
Sex Steroids ◽  
Direct Evidence ◽  
Venous Blood ◽  
Venous Blood Flow ◽  
Significant Suppression ◽  
Beagle Dogs ◽  
Adrenal Steroidogenesis ◽  
Adrenal Secretion ◽  
Secretion Rates ◽  
Acth Release

In the absence of functioning gonads, the adrenal is an important source of androgens and estrogens. In order to precisely quantitate the adrenal secretion rates of the sex steroids, we cannulated the adrenal veins and measured venous blood flow and arterial venous steroid gradients in adult male beagle dogs under pentobarbital anesthesia. Celite chromatography and specific radioimmunoassays were utilized to measure steroid levels. During basal conditions, the adrenal produced larger amounts of the androgens (667 ng/min of androstenedione, 5.45 ng/min of testosterone, and 3.43 ng/ min of dihydrotestosterone) than of the estrogens (1.245 ng/min of estradiol and 0.239 ng/min of estrone. These secretion rates were 20- to 50,000-fold less than that of cortisol (12,360 ng/min). Studies were also carried out during adrenal suppression with hydrocortisone to block ACTH release and with the adrenal steroidogenesis inhibitor, aminoglutethimide, plus hydrocortisone. The secretion rates of each androgen measured fell during ACTH inhibition. Significant suppression of estrone and estradiol, however, required addition of aminoglutethimide. This study provides direct evidence that the adrenal in the male dog can secrete estrogens, a previously controversial issue.

THE SPECIFIC ACTIVITY OF PLASMA CORTISOL IN SHEEP AFTER RAPID INTRAVENOUS INJECTION OF [1,2-3H2]CORTISOL, AND ITS RELATION TO THE RATE OF CORTISOL SECRETION

1965 ◽  
Vol 33 (3) ◽  
pp. 477-490 ◽  
Author(s):  
F. A. HARRISON ◽  
J. Y. F. PATERSON
Keyword(s):  
Single Dose ◽  
Evans Blue ◽  
Plasma Cortisol ◽  
Adrenal Glands ◽  
Specific Activity ◽  
Venous Blood ◽  
Cortisol Secretion ◽  
Half Time ◽  
Tracer Kinetic ◽  
Secretion Rates

SUMMARY Tritium-labelled cortisol was injected intravenously, as a single dose, in 12 experiments on seven sheep with autotransplanted left adrenal glands, in which cortisol secretion rate could be measured directly by sampling adrenal venous blood. In all experiments, curves which represented sums of two exponential terms could be fitted to the estimates of specific activity of plasma cortisol. The interpretation of the data was based on the distribution of cortisol in two miscible pools, and the calculated rates of cortisol turnover were much greater than the cortisol secretion rates which were measured directly and simultaneously. Simultaneous injection of Evans blue suggested that 1–2 min. was needed for complete mixing of the injected dose in plasma, during which time labelled cortisol leaves plasma with a half-time of about 1 min. It is concluded that such conditions do not provide a satisfactory basis for tracer kinetic analysis.

SECRETION OF THYROXINE, 3,5,3′-TRIIODOTHYRONINE AND 3,3′5′-TRIIODOTHYRONINE IN EUTHYROID MAN

1977 ◽  
Vol 84 (2) ◽  
pp. 281-289 ◽  
Author(s):  
U. Westgren ◽  
A. Melander ◽  
S. Ingemansson ◽  
A. Burger ◽  
S. Tibblin ◽  
...  
Keyword(s):  
Thyroid Gland ◽  
Venous Blood ◽  
Human Thyroid ◽  
Acute Administration ◽  
Peripheral Venous Blood ◽  
Before And After ◽  
Normal Human ◽  
Pre Treatment ◽  
Almost All ◽  
Secretion Rates

ABSTRACT The secretion of iodothyronines from the normal human thyroid gland was assessed by radioimmunoassay analyses of the concentrations of thyroxine (T4), 3,5,3′-triiodothyronine (T3) and 3,3′,5′-triiodothyronine (reverse T3, rT3) in thyroid venous and peripheral venous blood. The subjects studied were euthyroid patients undergoing parathyroid surgery. Measurements were carried out both under apparently normal conditions, following peroral T3 pre-treatment, and before and after acute administration of TSH into a thyroid artery. In the control subjects, significant gradients between thyroid venous and peripheral venous concentrations were recorded both for T4, T3 and rT3, suggesting that all three iodothyronines are secreted by the normal human thyroid. T3 pre-treatment seemed to reduce this secretion, and acute administration of TSH promoted rapid, marked, and concomitant increments in the thyroid venous concentrations of all three iodothyronines. Hence, it appears that not only T4 but also T3 and rT3 are secreted by the normal human thyroid gland, and that TSH stimulates the secretion of all three iodothyronines. On the other hand, calculations of the relative secretion rates yielded the relation T4:T3:rT3 as 85:9:1. This indicates that, in euthyroid subjects, most of T3, and almost all of rT3, is produced by extrathyroidal conversion of T4 and not by direct thyroidal secretion.

scholarly journals Equivalence of arterial and venous blood for [11C]CO2-metabolite analysis following intravenous administration of 1-[11C]acetate and 1-[11C]palmitate

2013 ◽  
Vol 40 (3) ◽  
pp. 361-365 ◽  
Author(s):  
Yen Ng ◽  
Steven P. Moberly ◽  
Kieren J. Mather ◽  
Clive Brown-Proctor ◽  
Gary D. Hutchins ◽  
...  
Keyword(s):  
Intravenous Administration ◽  
Venous Blood ◽  
Metabolite Analysis

TESTICULAR BLOOD FLOW AND TESTOSTERONE CONCENTRATIONS IN THE SPERMATIC VENOUS BLOOD IN RATS WITH EXPERIMENTAL CRYPTORCHIDISM

1978 ◽  
Vol 88 (3) ◽  
pp. 611-618 ◽  
Author(s):  
Jan-Erik Damber ◽  
Anders Bergh ◽  
Per Olof Janson
Keyword(s):  
Blood Flow ◽  
Leydig Cells ◽  
Venous Blood ◽  
Relative Increase ◽  
Morphological Data ◽  
Interstitial Tissue ◽  
Testicular Blood Flow ◽  
Cryptorchid Testis ◽  
Abdominal Testis ◽  
Main Factor

ABSTRACT Testicular blood flow and testosterone concentrations in the spermatic venous plasma were measured on unilaterally cryptorchid rats. Blood flow to the cryptorchid testis was 31.4 ± 11.7 (sd) ml/100 g x min which was significantly higher than that of the scrotal testis (17.7 ± 4.4 ml/100 gx. min) Stereological analysis showed a relative increase of blood vessel containing interstitial tissue in the cryptorchid testis, which was probably the main factor responsible for the relative increase of blood flow to the cryptorchid testis. The increase of interstitial tissue was greater than the increase of blood vessels and thus, the interstitium in the cryptorchid testis contained a number of vessels which was smaller than that of the interstitium in the scrotally located testis. The concentration of testosterone in the spermatic vein of the abdominal testis was 18.0 ± 5.5 (sd) ng/ml and the corresponding value for the scrotal testis was 41.2 ± 7.0 ng/ml. Calculations based on functional and morphological data indicate that the function of the Leydig cells in the abdominal testis was impaired. It was concluded that the outflow of testosterone from the cryptorchid testis was highly reduced.

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