Monolayer Cultures of Dispersed Cells from Bovine Anterior Pituitary: Responses to Synthetic Hypophysiotropic Peptides

1975 ◽  
Vol 53 (6) ◽  
pp. 1094-1098 ◽  
Author(s):  
G. Queen ◽  
S. Vivian ◽  
F. LaBella
Keyword(s):  
Growth Hormone ◽  
Luteinizing Hormone ◽  
Anterior Pituitary ◽  
Control Level ◽  
Thyroid Stimulating Hormone ◽  
Releasing Hormone ◽  
Cell Monolayers ◽  
Pituitary Glands ◽  
Lh Rh ◽  
Stimulating Hormone

Cells were dispersed from bovine anterior pituitary glands, by digestion with collagenase, and cultured. After 4 days the cell monolayers were incubated with fresh medium containing synthetic hypophysiotropic peptides for 2, 6, or 20 h, and hormone released into the medium was estimated by radioimmunoassay. After 2 h, thyroid releasing hormone (TRH) stimulated the release of thyroid-stimulating hormone (TSH) up to eightfold, and of prolactin (PRL) and follicle-stimulating hormone (FSH) about twofold at a minimal effective concentration of 1 ng/ml; enhanced growth hormone (GH) release was not apparent until 20 h, and release of luteinizing hormone (LH) and adrenocorticotrophic hormone (ACTH) was unaffected. Luteinizing hormone releasing hormone (LH-RH) enhanced release of LH maximally (three- to fourfold) during a 2 h incubation and was effective at 0.1 ng/ml; FSH release was significantly enhanced by about 50% above control level. Growth hormone release inhibiting hormone (GH-RIH) (somatostatin) showed significant effects only in the 20 h incubation; GH release was inhibited by 50% and release of PRL was slightly, but significantly, enhanced. Pituitary cell monolayers apparently permit maximal expression of releasing activities inherent in the hypothalamic hormones.

A RE-EXAMINATION OF THE TADPOLE IN METAMORPHIC STASIS AS A RECIPIENT IN A BIOASSAY FOR THYROID-STIMULATING HORMONE

1974 ◽  
Vol 61 (1) ◽  
pp. 15-19 ◽  
Author(s):  
MELVIN CHING
Keyword(s):  
Growth Hormone ◽  
Luteinizing Hormone ◽  
Thyroid Function ◽  
Anterior Pituitary ◽  
Rana Pipiens ◽  
Thyroid Stimulating Hormone ◽  
Pituitary Extract ◽  
Metamorphic Stage ◽  
Stimulating Hormone

SUMMARY The tadpole, in metamorphic stasis, has been used as a bioassay recipient for thyroid-stimulating hormone (TSH). The validity of its use for this purpose, however, has not been tested critically, particularly with respect to the effect of other hormones, most notably, growth hormone (GH) and luteinizing hormone (LH). Growth hormone has been shown to influence thyroid function and LH is a common contaminant of pituitary TSH preparations. Tadpoles of Rana pipiens, arrested at a particular metamorphic stage, received various concentrations of LH alone, a combination of doses of GH and TSH, or GH and rat anterior pituitary extract. Growth hormone was ineffective in re-inducing metamorphosis in 78% of cases, whereas LH stimulated metamorphosis in the tadpoles.

ELECTROPHORETIC SEPARATION OF HORMONES ASSOCIATED WITH SECRETORY GRANULES FROM RAT ANTERIOR PITUITARY GLANDS

1970 ◽  
Vol 63 (2) ◽  
pp. 378-384 ◽  
Author(s):  
D. R. Hodges ◽  
W. H. McShan
Keyword(s):  
Growth Hormone ◽  
Anterior Pituitary ◽  
Secretory Granules ◽  
Follicle Stimulating Hormone ◽  
Pituitary Hormones ◽  
Thyroid Stimulating Hormone ◽  
Disc Electrophoresis ◽  
Hormone Activity ◽  
Pituitary Glands ◽  
Stimulating Hormone

ABSTRACT Electrophoretic analyses of rat, mouse, human and cow anterior pituitary homogenates with subsequent bioassays for hormonal activity have been reported. Comparison of the behaviour of the hormonal activities from rat anterior pituitary secretory granules and that reported for pituitary homogenates was made following disc electrophoresis on polyacrylamide gels. Bioassays of gel segments for the six anterior pituitary hormones resulted in the localization of the activities of five of the six hormones. ACTH activity was not detected. Growth hormone and prolactin were associated with the major cathodal and anodal discs respectively. Luteinizing hormone and thyroid stimulating hormone activities had similar mobilities and were located in a zone just above growth hormone. The activity was not restricted to a discrete, stainable disc in either case. Follicle stimulating hormone activity was detected in a narrow segment containing only one disc a few millimeters below growth hormone. Comparison of the mobilities of the hormones from homogenates and secretory granule extracts suggests that they have essentially similar electrophoretic characteristics at basis pH.

Physiological role of galanin in the regulation of anterior pituitary function in humans

1994 ◽  
Vol 266 (1) ◽  
pp. E57-E61 ◽  
Author(s):  
A. Giustina ◽  
M. Licini ◽  
M. Schettino ◽  
M. Doga ◽  
G. Pizzocolo ◽  
...  
Keyword(s):  
Anterior Pituitary ◽  
Physiological Role ◽  
Thyroid Stimulating Hormone ◽  
Pituitary Function ◽  
Slight Reduction ◽  
Baseline Serum ◽  
Releasing Hormone ◽  
Anterior Pituitary Function ◽  
Stimulating Hormone

The aim of our study was to elucidate the physiological role of the neuropeptide galanin in the regulation of anterior pituitary function in human subjects. Six healthy men (age range 26-35 yr, body mass index range 20-24 kg/m2) underwent in random order 1) an intravenous bolus injection of growth hormone-releasing hormone (GHRH)-(1-29)-NH2 (100 micrograms) + thyrotropin-releasing hormone (TRH, 200 micrograms) + luteinizing hormone-releasing hormone (LHRH, 100 micrograms) + corticotropin-releasing hormone (CRH, 100 micrograms), and 2) intravenous saline (100 ml) at time 0 plus either human galanin (500 micrograms) in saline (100 ml) or saline (100 ml) from -15 to +30 min. Human galanin determined a significant increase in serum GH (GH peak: 11.3 +/- 2.2 micrograms/l) from both baseline and placebo levels. No significant differences were observed between GH values after galanin and those after GHRH alone (24.3 +/- 5.2 micrograms/l). Human galanin significantly enhanced the GH response to GHRH (peak 49.5 +/- 10 micrograms/l) with respect to either GHRH or galanin alone. Human galanin caused a slight decrease in baseline serum adrenocorticotropic hormone (ACTH; 16.3 +/- 2.4 pg/ml) and cortisol levels (8 +/- 1.5 micrograms/dl). Galanin also determined a slight reduction in both the ACTH (peak 27 +/- 8 pg/ml) and cortisol (peak 13.8 +/- 1.3 micrograms/dl) responses to CRH. Baseline and releasing hormone-stimulated secretions of prolactin, thyroid-stimulating hormone, LH, and follicle-stimulating hormone were not altered by galanin. Our data suggest a physiological role for the neuropeptide galanin in the regulation of GH secretion in humans.(ABSTRACT TRUNCATED AT 250 WORDS)

INHIBITION BY MELATONIN OF THE PITUITARY RESPONSE TO LUTEINIZING HORMONE RELEASING HORMONE IN VIVO

1978 ◽  
Vol 76 (3) ◽  
pp. 487-491 ◽  
Author(s):  
K. YAMASHITA ◽  
M. MIENO ◽  
T. SHIMIZU ◽  
ER. YAMASHITA
Keyword(s):  
Luteinizing Hormone ◽  
Carotid Artery ◽  
Anterior Pituitary ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Luteinizing Hormone Releasing Hormone ◽  
Releasing Hormone ◽  
Lh Rh ◽  
Lh Secretion

The rate of secretion of 17-oxosteroids by the testes of anaesthetized dogs in vivo was used as an index of LH secretion. Intracarotid injection of luteinizing hormone releasing hormone (LH-RH, 1, 5 or 10 μg/kg body wt) resulted in an increase in the testicular 17-oxosteroid secretion which was roughly proportional to the dose administered and which reached a maximum 60 min after the injection. Testicular output of 17-oxosteroids was unaffected by administration of melatonin (10 or 100 μg/kg body wt) into the carotid artery. When LH-RH (5 μg/kg) was injected into the carotid artery 3 h after intracarotid injection of melatonin (10 or 100 μg/kg), the testicular response to LH-RH was considerably diminished. Pretreatment with melatonin (100 μg/kg) did not alter the testicular response to human chorionic gonadotrophin (20 i.u./kg body wt) given i.v. It is concluded that melatonin may act directly on the anterior pituitary gland in dogs to inhibit the LH-RH-induced release of LH.

Stimulatory effect of thyrotrophin-releasing hormone (TRH) on the release of luteinizing hormone (LH) from rat anterior pituitary cells in vitro

1983 ◽  
Vol 61 (2) ◽  
pp. 186-189 ◽  
Author(s):  
Noboru Fujihara ◽  
Masataka Shiino
Keyword(s):  
Luteinizing Hormone ◽  
Anterior Pituitary ◽  
Pituitary Cells ◽  
Thyrotrophin Releasing Hormone ◽  
Releasing Hormone ◽  
Anterior Pituitary Cells ◽  
Lh Release ◽  
Lh Rh

The effect of thyrotrophin-releasing hormone (TRH, 10−7 M) on luteinizing hormone (LH) release from rat anterior pituitary cells was examined using organ and primary cell culture. The addition of TRH to the culture medium resulted in a slightly enhanced release of LH from the cultured pituitary tissues. However, the amount of LH release stimulated by TRH was not greater than that produced by luteinizing hormone – releasing hormone (LH–RH, 10−7 M). Actinomycin D (2 × 10−5 M) and cycloheximide (10−4 M) had an inhibitory effect on the action of TRH on LH release. The inability of TRH to elicit gonadotrophin release from the anterior pituitary glands in vivo may partly be due to physiological inhibition of its action by other hypothalamic factor(s).

Sensitivity of rat adenohypophyseal cells to estradiol and LHRH during long-term culture

1981 ◽  
Vol 240 (6) ◽  
pp. E602-E608
Author(s):  
L. Lagace ◽  
F. Labrie ◽  
T. Antakly ◽  
G. Pelletier
Keyword(s):  
Luteinizing Hormone ◽  
Cell Types ◽  
Thyroid Stimulating Hormone ◽  
Time Interval ◽  
Pituitary Cells ◽  
Luteinizing Hormone Releasing Hormone ◽  
Lh Release ◽  
Lh Rh ◽  
Stimulating Hormone

To determine possible effects of the time in culture on the responsiveness of the different pituitary cell types to estrogens, rat anterior pituitary cells were incubated up to 20 days in the presence or absence of 10 nM 17 beta-estradiol. Whereas spontaneous luteinizing hormone (LH) and thyroid-stimulating hormone (TSH) release decreased by 85-90%, follicle-stimulating hormone (FSH) and prolactin accumulation in medium were only 50% decreased after 20 days in culture, thus suggesting that the secretion of FSH and prolactin is less dependent on extrinsic stimulatory factors. Estradiol increased spontaneous LH release and its responsiveness to luteinizing hormone-releasing hormone (LH-RH) up to day 16 in culture, whereas the stimulatory effect of the estrogen on FSH secretion was significant only up to day 6. The stimulatory effect of estradiol on basal TSH release was seen up to day 8 in culture, whereas that on spontaneous prolactin release increased progressively after day 8 in culture up to the last time interval studied (20 days). As revealed by immunocytochemistry, the stimulatory effect of estradiol was not due to changes of cell growth.

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