Thyrotrophin and prolactin responses to thyrotrophin-releasing hormone in patients with Parkinson's disease

Abstract. The thyrotrophin (TSH) and prolactin (Prl)-releasing effects of TSH-releasing hormone (TRH) were investigated in 20 subjects with Parkinson's disease (PD), unmedicated, on chronic treatment with a combination levodopa-benserazide (Madopar) or levodopa-carbidopa (Sinemet) or withdrawn from therapy. Administration of TRH (200 μg iv) induced in unmedicated patients TSH and Prl responses significantly lower than those of sex-and age-matched controls. In patients on Madopar therapy the TSH and Prl responses to TRH were greater than in unmedicated patients and comparable to those of controls, while in patients on Sinemet therapy the pituitary responses were undistinguishable from those of unmedicated subjects. Withdrawal of Madopar therapy resulted in a marked diminution of the TSH response but did not affect the Prl response to TRH. Withdrawal of Sinemet therapy did not alter the TSH and Prl responses to TRH. Concomitant evaluation of growth hormone (GH) levels, in none of the subjects evidenced non-specific changes in plasma GH following TRH. Since TSH and Prl responses to TRH are inhibited by an enhancement of the dopaminergic tone, it would appear that the latter is preserved in the tuberoinfundibular system of unmedicated subjects and subjects on chronic Sinemet therapy, but is defective in subjects on chronic Madopar therapy.

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Hypothalamic hormones that release growth hormone stimulate hepatic 5′-monodeiodination activity in the chick embryo

Journal of Endocrinology ◽

10.1677/joe.0.1180233 ◽

1988 ◽

Vol 118 (2) ◽

pp. 233-236 ◽

Cited By ~ 14

Author(s):

E. R. Kühn ◽

A. Vanderpooten ◽

L. M. Huybrechts ◽

E. Decuypere ◽

V. Darras ◽

...

Keyword(s):

Growth Hormone ◽

Plasma Concentration ◽

Chick Embryo ◽

Chick Embryos ◽

Thyrotrophin Releasing Hormone ◽

Growth Hormone Releasing Factor ◽

Releasing Hormone ◽

Pancreatic Growth ◽

Hypothalamic Hormones ◽

Plasma Gh

ABSTRACT Plasma GH, tri-iodothyronine (T3), thyroxine (T4) and liver 5′-monodeiodination (5′-D) activity were measured in 18-day-old chick embryos injected with thyrotrophin-releasing hormone (TRH) and human pancreatic growth hormone releasing factor (hpGRF). Injections of 0·1 and 1 μg TRH and 1·5 μg hpGRF increased the concentration of plasma GH while injection of 15 μg hpGRF had no effect. Concentrations of plasma T3 were raised after injection of TRH or hpGRF. Injections of TRH but not of hpGRF raised the concentration of plasma T4. The increases in concentration of plasma T3 after injection of TRH or hpGRF were parallelled by increases in liver 5′-D activity. An injection of 0·25 μg T4 significantly raised the concentration of T4 in plasma but had no effect on plasma T3 or liver 5′-D activity. It is concluded that the release of chicken GH by TRH or hpGRF is responsible for the observed increases in plasma concentration of T3 and liver 5′-D activity. J. Endocr. (1988) 118, 233–236

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INTRAVENOUS THYROTROPHIN-RELEASING HORMONE IN PARKINSON'S DISEASE

The Lancet ◽

10.1016/s0140-6736(74)92939-0 ◽

1974 ◽

Vol 303 (7860) ◽

pp. 735 ◽

Cited By ~ 21

Author(s):

J.A. Mccaul ◽

K.J. Cassell ◽

G.M. Stern

Keyword(s):

Parkinson’S Disease ◽

Parkinson's Disease ◽

Thyrotrophin Releasing Hormone ◽

Releasing Hormone

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Effects of hypothyroidism on the growth hormone axis in sheep

Journal of Endocrinology ◽

10.1677/joe.0.1400495 ◽

1994 ◽

Vol 140 (3) ◽

pp. 495-502 ◽

Cited By ~ 9

Author(s):

T P Fletcher ◽

I J Clarke

Keyword(s):

Growth Hormone ◽

Pulse Amplitude ◽

Pulse Frequency ◽

Pulse Interval ◽

Short Term ◽

Thyrotrophin Releasing Hormone ◽

Releasing Hormone ◽

Gh Secretion ◽

Prolactin Response ◽

Plasma Gh

Abstract This study examined the effect of thyroidectomy (TX) on the GH axis in sheep. The secretion of GH was monitored 10 and 77 days after TX or sham-TX when the effects on plasma GH and prolactin levels of the injection of 0·5 μg GH-releasing factor (GRF)/kg and 1 μg thyrotrophin-releasing hormone (TRH)/kg were also assessed. There were no significant differences in GH pulse amplitude, pulse frequency, inter-pulse interval and GH secreted/h between sham-TX and TX animals at 10 or 77 days after TX. There was no difference in the GH response to GRF injection in sham-TX sheep at any time but in TX sheep the GH response was significantly (P<0·05) attenuated 10 days after TX. After 77 days the GH response was similar to the response before TX. There was no measurable GH response to injection of TRH in sham-operated or TX sheep at any time. The prolactin response to TRH was not affected by TX or sham-TX. These results suggest that TX in sheep does not affect GH secretion but paradoxically the response to GRF is attenuated in hypothyroid sheep in the short term. TRH causes release of prolactin but not GH in sheep. Journal of Endocrinology (1994) 140, 495–502

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GROWTH HORMONE RELEASE FOLLOWING THYROTROPHIN-RELEASING HORMONE INJECTION INTO PATIENTS WITH ANOREXIA NERVOSA

Acta Endocrinologica ◽

10.1530/acta.0.0810001 ◽

1976 ◽

Vol 81 (1) ◽

pp. 1-8 ◽

Cited By ~ 96

Author(s):

K. Maeda ◽

Y. Kato ◽

N. Yamaguchi ◽

K. Chihara ◽

S. Ohgo ◽

...

Keyword(s):

Growth Hormone ◽

Anorexia Nervosa ◽

Luteinizing Hormone ◽

Intravenous Injection ◽

Thyrotrophin Releasing Hormone ◽

Releasing Hormone ◽

Basal Plasma ◽

Plasma Gh ◽

Lh Rh ◽

Plasma Prl

ABSTRACT The effect of thyrotrophin-releasing hormone (TRH) or luteinizing hormone-releasing hormone (LH-RH) on plasma levels of growth hormone (GH), prolactin (PRL), thyrotrophin (TSH), and luteinizing hormone (LH), were studied in patients with anorexia nervosa. The basal plasma GH levels were elevated in 6 of 11 patients studied. Intravenous injection of synthetic TRH (500 μg) significantly raised the plasma GH levels in 9 of 11 patients. The peak values of plasma GH after TRH ranged from 6.0 to 31.5 ng/ml. Plasma GH concentrations also increased following the administration of synthetic LH-RH (100μg) in 1 of 7 patients. The intravenous injection of saline solution caused no significant change in plasma GH in these patients. The plasma LH responses to LH-RH were significantly blunted in all patients, whereas the plasma PRL and TSH responses to TRH were almost normal in the patients examined. These results suggest that the hypothalamo-pituitary function regulating GH and LH secretion is altered in patients with anorexia nervosa.

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DYNAMIC EVALUATION OF GROWTH HORMONE (GH) AND PROLACTIN (hPRL) SECRETION IN ACTIVE ACROMEGALY WITH HIGH AND LOW GH OUTPUT

Acta Endocrinologica ◽

10.1530/acta.0.0780251 ◽

1975 ◽

Vol 78 (2) ◽

pp. 251-257 ◽

Cited By ~ 16

Author(s):

G. Tolis ◽

L. Kovacs ◽

H. Friesen ◽

J. B. Martin

Keyword(s):

Growth Hormone ◽

Fasting Serum ◽

Thyrotrophin Releasing Hormone ◽

Dynamic Evaluation ◽

Releasing Hormone ◽

Active Acromegaly ◽

Plasma Gh ◽

Serum Gh

ABSTRACT Ten patients with active acromegaly were studied. In 9 plasma GH levels failed to suppress after glucose (OGTT), in 8 an increase in serum GH occurred after thyrotrophin releasing hormone (TRH). After L-Dopa, 4 patients showed no change in serum GH, 3 exhibited a decrease and in 3 an increase in serum hGH occurred. With a combined insulin (ITT) and arginine (ATT) test, 2 patients exhibited an increase in hGH, and in 6 no change occurred. Fasting serum GH concentration was less than 11 ng/ml in 5 patients. Basal prolactin (hPRL) levels were normal in all patients including two with galactorrhea. L-Dopa suppressed and TRH stimulated hPRL secretion in all, but the responses which were seen were subnormal. Hydrocortisone infusion in two acromegalics did not affect the prolactin induced increase after TRH but blunted the GH increase after TRH.

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A decreased capacity of hepatic growth hormone (GH) receptors and failure of thyrotrophin-releasing hormone to stimulate the peripheral conversion of thyroxine into triiodothyronine in sex-linked dwarf broiler hens

Reproduction Nutrition Development ◽

10.1051/rnd:19890407 ◽

1989 ◽

Vol 29 (4) ◽

pp. 461-467 ◽

Cited By ~ 11

Author(s):

E. R. Kühn ◽

L. M. Huybrechts ◽

A. Vanderpooten ◽

L. Berghman

Keyword(s):

Growth Hormone ◽

Thyrotrophin Releasing Hormone ◽

Releasing Hormone ◽

Peripheral Conversion ◽

Gh Receptors

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Clinical Aspects and Management of Levodopa-Induced Dyskinesia

Parkinson s Disease ◽

10.1155/2012/745947 ◽

2012 ◽

Vol 2012 ◽

pp. 1-12 ◽

Cited By ~ 4

Author(s):

Nicola Tambasco ◽

Simone Simoni ◽

Erica Marsili ◽

Elisa Sacchini ◽

Donatella Murasecco ◽

...

Keyword(s):

Parkinson’S Disease ◽

Parkinson's Disease ◽

Dopamine Agonists ◽

Chronic Treatment ◽

Clinical Impact ◽

Clinical Aspects ◽

Pharmacological Profile ◽

Early Use

In Parkinson's disease, one of the most troublesome dilemmas is the treatment of levodopa-induced dyskinesia. After a few years, chronic treatment with levodopa is associated with the development of dyskinesias. Strategies to delay or to reduce dyskinesias are based on the change of levodopa dosing or the early use of dopamine agonists. Dopamine agonists with different pharmacological profile are available. Our paper was aimed to analyse the clinical impact and the management of dyskinesias with dopamine agonists.

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Psychotic and Depressive Symptoms in Parkinson's Disease a Study of the Growth Hormone Response to Apomorphine

The British Journal of Psychiatry ◽

10.1192/bjp.167.4.522 ◽

1995 ◽

Vol 167 (4) ◽

pp. 522-526 ◽

Cited By ~ 10

Author(s):

John D. C. Mellers ◽

Niall P. Quinn ◽

Maria A. Ron

Keyword(s):

Parkinson’S Disease ◽

Growth Hormone ◽

Parkinson's Disease ◽

Depressive Symptomatology ◽

Past History ◽

Visual Hallucinations ◽

Hormone Response ◽

Receptor Sensitivity ◽

Dopaminergic Mechanisms ◽

History Of

BackgroundThe growth hormone (GH) response to apomorphine, thought to reflect central dopaminergic receptor sensitivity, has been reported as enhanced in acute schizophrenia. We investigated this response in relation to the psychotic episodes associated with Parkinson's disease (PD).MethodThe GH response to apomorphine was measured in three groups of patients with Parkinson's disease: those currently psychotic (n = 9), those with a past history of psychosis (n = 7) and those who had never been psychotic (n = 8).ResultsApomorphine-induced GH response was not related to psychosis but was unexpectedly associated with measures of depression.ConclusionsVisual hallucinations were a prominent feature in the psychotic patients and the atypical nature of these psychoses might explain why we found no evidence of dopaminergic sensitivity. Serotonergic dysfunction would be in keeping with this. Dopaminergic mechanisms may contribute to the minor depressive symptomatology seen in PD.

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