TAIL GROWTH IN THE THYROXINE-TREATED HYPOPHYSECTOMIZED RAT AS A SENSITIVE CRITERION FOR GROWTH HORMONE ACTIVITY

ABSTRACT Tail measurements were performed on hypophysectomized rats sensitized to growth hormone by simultaneous treatment with thyroxine; three weeks of daily injections suffice to differentiate the standard (continuous) thyroxine growth from the additional growth caused by growth hormone. It was found necessary to select the rats according to tail length.

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GROWTH HORMONE AND RADIO-SULFATE INCORPORATION IN COSTAL CARTILAGE

Acta Endocrinologica ◽

10.1530/acta.0.0370176 ◽

1961 ◽

Vol 37 (2) ◽

pp. 176-182 ◽

Cited By ~ 4

Author(s):

Elliott J. Collins ◽

Vernon F. Baker

Keyword(s):

Growth Hormone ◽

Costal Cartilage ◽

Time Response ◽

Hormone Activity ◽

Reliable Estimation ◽

Hypophysectomized Rats ◽

Related Response ◽

Sulfate Incorporation

ABSTRACT The characteristics and nature of the effect of growth hormone on the incorporation of radio-sulfate into the costal cartilage of hypophysectomized rats has been studied. The time-response studies indicate that a reliable estimation of growth hormone activity can be ascertained within a 24 hour period, and a reproducible dose-related response can be obtained at dosage levels ranging from 12-48 μg. Growth hormone stimulates the synthesis of organic sulfates and accumulation of inorganic sulfates within 48 hours.

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Bioassayable growth hormone activity in blood from healthy individuals and acromegalic patients

Acta Endocrinologica ◽

10.1530/acta.0.1110003 ◽

1986 ◽

Vol 111 (1) ◽

pp. 3-9

Author(s):

Karl-Göran Thorngren ◽

Bengt Hallengren

Keyword(s):

Growth Hormone ◽

Bone Growth ◽

Normal Subjects ◽

Healthy Individuals ◽

Hormone Activity ◽

Longitudinal Bone Growth ◽

Biological Growth ◽

Hypophysectomized Rats ◽

Growth Activity

Abstract. Biological growth activity (bioassayable GH) was determined in blood from healthy individuals and from patients with acromegaly using the rate of longitudinal bone growth in hypophysectomized rats with tetracycline as intravital marker. Also radioimmunoassayable GH and somatomedin A activity were determined. In pooled plasma or serum from normal subjects no bioassayable growth activity was demonstrated. In the clinically active acromegalic patients as a group as well as in one individual patient there was a significant (P <0.05) bioassayable growth activity in serum as compared to serum from normal subjects. The bioassay determination of GH in plasma/serum from normal subjects and acromegalic patients was hampered by the toxicity and the problems connected with the administration of large volumes.

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GROWTH RETARDATION: USE OF SULFATION FACTOR AS A BIOASSAY FOR GROWTH HORMONE

PEDIATRICS ◽

10.1542/peds.31.4.538 ◽

1963 ◽

Vol 31 (4) ◽

pp. 538-551

Author(s):

Maurice D. Kogut ◽

S. A. Kaplan ◽

C. S. N. Shimizu

Keyword(s):

Growth Hormone ◽

Human Growth ◽

Hormone Activity ◽

Normal Children ◽

Immature Rat ◽

Pituitary Diseases ◽

Hypophysectomized Rats ◽

Normal Human ◽

The Mean

A bioassay for measurement of human growth hormone based upon the observation that normal human serum, in vitro, will favor the incorporation of S-35 into immature rat cartilage is described. The factor in serum is called "sulfation factor." Sulfation factor determinations were performed on 27 normal children, 15 with hypopituitarism, 26 dwarfs without demonstrable endocrine or other diseases, 11 children with a variety of non-pituitary diseases causing dwarfism, and 1 adult with acromegaly. The mean activity (± S. E.) of sulfation factor was 0.84 ± 0.057 S. F. units in the normal children, 0.45 ± 0.024 S. F. units in idiopathic hypopituitary patients (p < 0.01), 0.95 ± 0.054 S. F. units in dwarfs without evidence of endocrine or other recognizable diseases, 0.82 ± 0.057 S. F. units in dwarfs with well recognized nonpituitary disease, and 2.2 S. F. units in one adult with acromegaly. There was an excellent correlation between sulfation factor and other laboratory determinations of pituitary function. Hypophysectomized rats receiving bovine growth hormone showed substantial increase of sulfation factor as compared to control hypophysectomized rats. Sulfation factor activity appears to be a valid and useful indicator of growth hormone activity in serum.

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MODIFICATION BY OESTROGENS OF THE REACTION OF THE RAT'S MAMMARY GLAND TO ANDROGENS

Acta Endocrinologica ◽

10.1530/acta.0.0410088 ◽

1962 ◽

Vol 41 (1) ◽

pp. 88-100 ◽

Cited By ~ 4

Author(s):

Dora Jacobsohn

Keyword(s):

Growth Hormone ◽

Mammary Gland ◽

Present Finding ◽

Mammary Glands ◽

List Type ◽

Simultaneous Treatment ◽

Alveolar Development ◽

Hypophysectomized Rats ◽

Combined Actions

ABSTRACT The investigation is concerned with the question, whether the mammary gland of the rat reacts with alveolar growth to androgens alone or to the combined actions of androgens and oestrogens. Since it is difficult to deprive a rat of oestrogens, the study was performed under conditions in which the gland itself either does or does not react to oestrogens. The results were as follows: Experiments on hypophysectomized rats treated with insulin and cortisone. – This treatment makes the glands responsive to oestrogens. Administration of oestrogens resulted in alveolar development in response to endogenously produced androgens (males injected with PMS) as well as to testosterone injections (gonadectomized rats). Experiments on hypophysectomized rats. – The glands do not react to oestrogens. – Injections of oestrogens together with PMS or testosterone resulted in the abnormal reaction known to occur in the mammary glands of hypophysectomized rats given androgens alone. Alveoli were absent. Confirming previous results with testosterone, the mammary glands of hypophysectomized males injected with PMS reacted abnormally and the reaction was not normalized by simultaneous treatment of the hypophysectomized rats with insulin and cortisone. The hitherto confusing results obtained by other workers who studied the effects of growth hormone and prolactin on the mammary glands of hypophysectomized rats are discussed, in view of the present finding that a response of the rat's mammary gland to oestrogens is a prerequisite for the production of alveolar lobule development by androgens.

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SENSITIVITY OF THE RAT DIAPHRAGM TO GROWTH HORMONE.

Acta Endocrinologica ◽

10.1530/acta.0.0540645 ◽

1967 ◽

Vol 54 (4) ◽

pp. 645-662 ◽

Cited By ~ 8

Author(s):

Å. Hjalmarson ◽

K. Ahrén

Keyword(s):

Growth Hormone ◽

Inhibitory Effect ◽

Rat Diaphragm ◽

Intracellular Accumulation ◽

Slight Effect ◽

Kidney Capsule ◽

Muscle Tissues ◽

Hypophysectomized Rats ◽

Isolated Rat

ABSTRACT The effect of growth hormone (GH) in vitro on the rate of intracellular accumulation of the non-utilizable amino acid α-aminoisobutyric acid (AIB) was studied in the intact rat diaphragm preparation. Bovine or ovine GH (25 μg/ml incubation medium) markedly stimulated the accumulation of AIB-14C by diaphragms from hypophysectomized rats, while there was no or only a very slight effect on diaphragms from normal rats. In diaphragms from rats with the pituitary gland autotransplanted to the kidney capsule GH in vitro stimulated the accumulation of AIB-14C significantly more than in diaphragms from normal rats but significantly less than in diaphragms from hypophysectomized rats. Injections of GH intramuscularly for 4 days to hypophysectomized rats made the diaphragms from these rats less sensitive or completely insensitive to GH in vitro. These results indicate strongly that the relative insensitivity to GH in vitro of diaphragms from normal rats is due to the fact that the muscle tissues from these rats has been exposed to the endogenously secreted GH. The results show that GH can influence the accumulation of AIB-14C in the isolated rat diaphragm in two different ways giving an acute or »stimulatory« effect and a late or »inhibitory« effect, and that it seems to be a time-relationship between these two effects of the hormone.

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THE EXTRACTION OF PROLACTIN FROM HUMAN PITUITARY GLANDS

Acta Endocrinologica ◽

10.1530/acta.0.0490001 ◽

1965 ◽

Vol 49 (1) ◽

pp. 1-16 ◽

Cited By ~ 12

Author(s):

M. Apostolakis

Keyword(s):

Growth Hormone ◽

Pituitary Gland ◽

List Type ◽

Distilled Water ◽

Hormone Activity ◽

Isoelectric Precipitation ◽

Human Pituitary ◽

Pituitary Glands ◽

Prolactin Content ◽

The Mean

ABSTRACT A method for the extraction of prolactin from human pituitary glands is described. It is based on acetone drying, distilled water extraction, acetone and isoelectric precipitation. Two main products are obtained: Fraction R8 with a mean prolactin activity of 12.2 IU/mg and fraction U8 with a mean prolactin activity of 8.6 IU/mg. The former fraction does not contain any significant gonadotrophin activity and the latter contains on an average 50 HMG U/mg. In both cases contamination with ACTH and MSH is minimal. The growth hormone activity of both these fractions is low. It is postulated that in man too, prolactin and growth hormone are two distinct hormones. A total of 1250 human pituitary glands have been processed by this method. The mean prolactin content per pituitary gland has been found to be 73 IU.

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BIOASSAY OF GROWTH HORMONE

Acta Endocrinologica ◽

10.1530/acta.0.0750669 ◽

1974 ◽

Vol 75 (4) ◽

pp. 669-682 ◽

Cited By ~ 1

Author(s):

K.-G. Thorngren ◽

L. I. Hansson

Keyword(s):

Growth Hormone ◽

Bone Growth ◽

Control Period ◽

Growth Stimulation ◽

Sprague Dawley ◽

Hormone Administration ◽

Sprague Dawley Rats ◽

Hypophysectomized Rats ◽

Operative Control ◽

Sensitivity Specificity

ABSTRACT The growth stimulating effect of growth hormone was determined with tetracycline as intravital marker of the longitudinal bone growth of proximal tibia in female Sprague-Dawley rats hypophysectomized at 60 days of age. After a post-operative control period of 15 days growth hormone (NIH-GH-B16) was given daily for 5 or 10 days followed by a 10 day period after its withdrawal. L-thyroxine was given in association with the growth hormone administration to potentiate the growth stimulation. A linear log dose-response relation was found for the two administration models with a high precision. The thyroxine-treatment increased the sensitivity of the bioassay. An administration period of 5 days was found sufficient for the bioassay of growth hormone in thyroxine-treated hypophysectomized rats. Compared with the earlier bioassay methods for growth hormone, the present bioassay is more favourable when all the factors, such as precision, sensitivity, specificity, and administration period are considered.

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ANALYSIS OF THE BIPHASIC ACTION OF GROWTH HORMONE IN VITRO ON THE RAT DIAPHRAGM

Acta Endocrinologica ◽

10.1530/acta.0.057s019 ◽

1968 ◽

Vol 57 (3_Suppl) ◽

pp. S19-S35 ◽

Cited By ~ 9

Author(s):

Å. Hjalmarson

Keyword(s):

Growth Hormone ◽

Actinomycin D ◽

Accumulation Rate ◽

Inhibitory Effect ◽

Bovine Growth Hormone ◽

Rat Diaphragm ◽

Dual Nature ◽

Hypophysectomized Rats ◽

D 20

ABSTRACT In vitro addition of bovine growth hormone (GH) to intact hemidiaphragms from hypophysectomized rats has previously been found to produce both an early stimulatory effect lasting for 2—3 hours and a subsequent late inhibitory effect during which the muscle is insensitive to further addition of GH (Hjalmarson 1968). These effects on the accumulation rate of α-aminoisobutyric acid (AIB) and D-xylose have been further studied. In presence of actinomycin D (20 μg/ml) or puromycin (100 μg/ml) the duration of the stimulatory effect of GH (25 μg/ml) was prolonged to last for at least 4—5 hours and the late inhibitory effect was prevented. Similar results were obtained when glucose-free incubation medium was used. Preincubation of the diaphragm at different glucose concentrations (0—5 mg/ml) for 3 hours did not change the GH sensitivity. Addition of insulin at start of incubation could not prevent GH from inducing its late inhibitory effect, while dexamethasone seemed to potentiate this effect of GH. Furthermore, adrenaline was found to decrease the uptake of AIB-14C and D-xylose-14C in the diaphragm, but not to change the sensitivity of the muscle to GH. Preincubation of the diaphragm for 3 hours with puromycin in a concentration of 200 μg/ml markedly decreased the subsequent basal uptake of both AIB-14C and D-xylose-14C, in the presence of puromycin, and abolished the stimulatory effect of GH on the accumulation of AIB-14C. However, the effect of GH on the accumulation of D-xylose-14C was unchanged. The present observations are discussed and evaluated in relation to various mechanisms of GH action proposed to explain the dual nature of the hormone.

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