Showing papers in "Hormone Research in Paediatrics in 1984"
TL;DR: Like in women, decline of gonadic function determines an increased bone resorption in men too, and a positive linear correlation is evident between PCA and testosterone, androstenedione and estrone plasma levels.
Abstract: The bone mineral content was evaluated in 30 male subjects aged between 60 and 90 years using the relief of the percent cortical area (PCA) at the level of the second phalanx of the left-hand index fi
98 citations
TL;DR: Solid-phase extraction and assay by HPLC provides a rapid and specific method for the simultaneous determination of plasma glucocorticoids.
Abstract: This study describes a method for the extraction and simultaneous measurement of cortisone, cortisol and corticosterone using dexamethasone as an internal standard. Solid-phase extraction of plasma steroids with C18 columns allows the samples to be extracted, washed and concentrated in a single step with minimal sample handling and without the use of large volumes of organic solvents. HPLC separation of the steroids is accomplished within 10 min and the individual steroid peaks are quantitated by UV detection at 239 nm. This assay was examined for linearity, extraction efficiency, precision and potential interference by commonly used drugs. Plasma values of glucocorticoids are reported for samples obtained from human subjects as well as from rats. HPLC was also compared to RIA for the determination of plasma levels of corticosterone in the rat. Solid-phase extraction and assay by HPLC provides a rapid and specific method for the simultaneous determination of plasma glucocorticoids.
70 citations
TL;DR: A decreased corticosterone response to noise was observed in chronically stressed rats, but the pituitary-thyroid response was the same in control and chronically stressed Rats, suggesting that the mechanisms which control the responsiveness of both axes to a repeated stimulus are dissociated.
Abstract: The effects of acute and chronic stress on serum corticosterone and pituitary-thyroid hormones were studied in male Wistar rats. Acute noise activated both the pituitary-adrenal and pituitary-thyroid axes. Chronic noise did not modify the basal serum levels of either corticosterone or pituitary-thyroid hormones. A decreased corticosterone response to noise was observed in chronically stressed rats, but the pituitary-thyroid response was the same in control and chronically stressed rats, suggesting that the mechanisms which control the responsiveness of both axes to a repeated stimulus are dissociated.
47 citations
TL;DR: Myoglobin and creatine kinase have proved to be the best indicators of the hypothyroid myopathy, since they are sensitive for the early detection of muscle involvement due to the metabolic disorder and are closely correlated toThe metabolic conditions of patients.
Abstract: An accurate and close follow-up of serum levels of thyroid hormones and various muscle markers (myoglobin, creatine kinase and its isoenzymes CK-MB and CK-BB, lactic dehydrogenase, α-hydroxybutyric de
44 citations
TL;DR: It is concluded that prolactin is an adrenocortical secretagogue of physiological relevance in the rat, and that it could play a role in enhancing the action of ACTH to acutely release steroids.
Abstract: Prolactin, alone and in combination with ACTH, was tested for its ability to release steroids from rat adrenocortical slices superfused in vitro. The hormone possessed weak activity alone (minimal responsive dose = 1 U), but was able to potentiate the ACTH-stimulated corticoid release at much lower doses (significant response over ACTH alone at 0.01 U prolactin). This latter dosage was calculated to be within the physiologic range of prolactin in blood. Analysis of individual steroids in superfusate by RIA revealed that aldosterone release was most sensitive to prolactin, followed by corticosterone, androstenedione, and progesterone. We conclude that prolactin is an adrenocortical secretagogue of physiological relevance in the rat, and that it could play a role in enhancing the action of ACTH to acutely release steroids.
35 citations
TL;DR: Preliminary results suggest that hydrocortisone given in two divided doses during the day, supplemented by a small dose of prednisolone at bedtime, is suitable treatment for CAH patients who are still growing and single daily dose dexamethasone therapy ensures adequate adrenal suppression and is convenient in the longterm.
Abstract: Treatment in a group of 19 patients with congenital adrenal hyperplasia (CAH) has been monitored by frequent, serial measurements of saliva 17OH-progesterone (17OHP) concentrations. Detailed 17OHP profiles were obtained during consecutive weekend days and every 1-2 h over a separate 24-hour period. Patients showed a marked diurnal rhythm in 17OHP levels, particularly when treated with hydrocortisone. In some patients, 10 mg/m2/day of hydrocortisone was sufficient glucocorticoid replacement to produce adequate control, although there was considerable individual variation. Saliva 17OHP profiles provided valuable information on the efficacy of hydrocortisone, cortisone acetate, prednisolone and dexamethasone as glucocorticoid suppressive regimes in the treatment of CAH. Preliminary results suggest that hydrocortisone given in two divided doses during the day, supplemented by a small dose of prednisolone at bedtime, is suitable treatment for CAH patients who are still growing. In the patient who has completed statural growth, single daily dose dexamethasone therapy ensures adequate adrenal suppression and is convenient in the longterm.
31 citations
31 citations
TL;DR: Testicular atrophy and decreased plasma luteinizing hormone (LH) levels were observed in the adult male rat after treatment with 500 µg of estradiol benzoate (EB) on the first day of life.
Abstract: Testicular atrophy (TA) and decreased plasma luteinizing hormone (LH) levels were observed in the adult male rat after treatment with 500 µg of estradiol benzoate (EB) on the first day of life, while
31 citations
TL;DR: The results suggest that high doses of oxytocin affect beta-cell function in normal man.
Abstract: Inthis study we have examined the effect of the administration of oxytocin on basal blood concentrations of insulin, glucagon, cortisol, growth hormone, and on the dynamic secretory response of these hormones to intravenous glucose administration (0.33 g/kg) in basal condition and after the injection of 3 IU (1 plus 2 IU/1 h) or 6 IU (2 plus 4 IU/ 1 h) of oxytocin (6 subjects for each group). The highest dose of oxytocin (6 IU) used significantly increased insulin secretion in response to intravenously administered glucose. No significant change of insulin secretion was observed with 3 IU of oxytocin. Glucagon, cortisol, and growth hormone response to intravenous injection of glucose was not affected by oxytocin (3 or 6 IU) administration. These results suggest that high doses of oxytocin affect β-cell function in normal man.
28 citations
TL;DR: The results indicate that pituitary-adrenal regulation in man is more complex than the traditional model of ACTH-cortisol feedback would predict and further evidence for ACTH independent regulation of adrenal function is found.
Abstract: We examined the plasma cortisol and ACTH concentrations after graded doses of dexamethasone in a group of young, healthy adults. The decrease in cortisol was uniform in all subjects, and in 8 subjects there was a high degree of correspondence with the plasma ACTH concentration. The remaining 5 subjects had no change in plasma ACTH concentration during dexamethasone administration. All subjects had an expected diurnal change in cortisol on 2 pretreatment days and there was a corresponding diurnal change in ACTH for those subjects who had associated ACTH and cortisol responses after dexamethasone, while those with dissociated ACTH and cortisol after dexamethasone had no diurnal ACTH pattern. These findings were consistent with the 24-hour pattern of ACTH and cortisol before and after 1.0 mg of dexamethasone in 2 of the same subjects. These results are further evidence for ACTH independent regulation of adrenal function and indicate that pituitary-adrenal regulation in man is more complex than the traditional model of ACTH-cortisol feedback would predict.
21 citations
TL;DR: In this paper, morphometric measurements of the genomic responses correlated with a classically accepted biochemical method of genomic response evaluation in the uterus (increase in RNA/DNA), which correlated with the estrogen-induced increase in uterine wet weight 6 h after hormone administration.
Abstract: Nongenomic responses to estrogen and the genomic responses in the different uterine cell types can be dissociated selectively. The present report describes morphometric methods for the evaluation of estrogen-induced uterine edema and of genomic responses in individual cell types. The morphometric measurements of the genomic responses correlated with a classically accepted biochemical method of genomic response evaluation in the uterus (increase in RNA/DNA). Edema correlated with the classically accepted method of evaluation of uterine water imbibition, i.e., estrogen-induced increase in uterine wet weight 6 h after hormone administration.
TL;DR: Measurement of daily salivary progesterone values in subfertile women for time spans exceeding 3 months allowed accurate assessment of base-line ovarian activity and of the response to ovulation-induction therapy.
Abstract: A ‘normal range’ for salivary progesterone concentrations has been established using data derived from women who were menstruating regularly and in whom dating of the cycle by accepted criteria was po
TL;DR: The enzymatic system or systems involved appear to be linked to the concentration of CA used but, whatever the case, the drop in cortisol production is accompanied by a decrease in aldosterone and an increase in adrenal androgen levels.
Abstract: The effects of cyproterone acetate (CA) on steroidogenesis in isolated guinea-pig adrenal cells have been investigated by measuring the production of cortisol, its immediate precursors (11-deoxycortisol and 17-hydroxyprogesterone), and adrenal androgens (Δ4-androstenedione and dehydroepiandrosterone). Used at a dose of 2 µg/ml, CA provoked a sharp drop in the production of cortisol, aldosterone and 11-deoxycortisol. By contrast, 17-hydroxyprogesterone, Δ4-androstenedione and dehydroepiandrosterone were increased, which suggests that 21 -hydroxylase activity is inhibited. With concentrations above 2 µg/ml CA, it would seem to be the 3-β-ol-dehydrogenase-Δ4,5-isomerase complex that is affected, since dehydroepiandrosterone exhibited a sudden increase, whereas 17-hydroxyprogesterone and Δ4-androstenedione showed a relative decrease. The enzymatic system or systems involved therefore appear to be linked to the concentration of CA used but, whatever the case, the drop in cortisol production is accompanied by a decrease in aldosterone and an increase in adrenal androgen levels.
TL;DR: Antral, duodenal, and serum gastrin levels and colonic thymidine kinase activity were determined in 1- to 4-day- fasted rats and after refeeding of 4- day-fasted rats for 3-24 h, and the effect of pentagastrin on colonic THK activity was determined.
Abstract: Antral, duodenal, and serum gastrin levels and colonic thymidine kinase activity were determined in 1- to 4-day-fasted rats and after refeeding of 4-day-fasted rats for 3–24 h. The effect of pentagast
TL;DR: These data, while confirming the existence of a functional derangement in the neural inhibitory control of PRL secretion in hyperprolactinemia either due to a PRL-secreting pituitary microadenoma or so-called 'idiopathic', do not agree with the hypothesis that tubero-infundibular DA hyperactivity inhibits gonadotropin secretion inHyperProlactinemic patients.
Abstract: To investigate the role of catecholamines in the control of gonadotropin and prolactin release, we examined the effects of a catecholamine synthesis inhibitor (alpha-methyl-p-tyrosine, AMPT) administration and those of dopamine (DA) or epinephrine (EPI) infusion after endogenous catecholamine synthesis inhibition, on FSH, LH and PRL serum levels, in regularly cycling women and in patients with hyperprolactinemic amenorrhea. AMPT administration was followed by a prompt increase in serum PRL in regularly cycling women, but not in women with hyperprolactinemia either due to a PRL-secreting pituitary microadenoma or 'idiopathic'. Gonadotropin serum levels did not show any significant variation after AMPT in both normal and hyperprolactinemic women. DA infusion after endogenous catecholamine synthesis inhibition by AMPT, induced an appreciable decline in PRL levels in both normal and hyperprolactinemic subjects. Although the net decrements were higher in the hyperprolactinemic group, the PRL fall was similar in the two groups when expressed as a percentage of preinfusion PRL concentrations. LH serum levels similarly fell during DA infusion in normal women and in hyperprolactinemic patients, while FSH concentrations did not show any significant change. EPI infusion after analogous AMPT pretreatment was followed by an evident decrease in serum PRL in both normal and hyperprolactinemic subjects. No significant changes in FSH and LH serum concentrations were observed during EPI administration. These data, while confirming the existence of a functional derangement in the neural inhibitory control of PRL secretion in hyperprolactinemia either due to a PRL-secreting pituitary microadenoma or so-called 'idiopathic', do not agree with the hypothesis that tubero-infundibular DA hyperactivity inhibits gonadotropin secretion in hyperprolactinemic patients. The inhibitory action of exogenously administered DA might represent rather a pharmacological effect than express a physiological inhibitory role of hypothalamic DA pathway on gonadotropin secretion in humans.
TL;DR: Binding studies of [3H]-spiroperidol indicate that dopaminergic binding sites are present in some GH-secreting adenomas in the absence of PRL hypersecretion and in some 'nonSecreting' pituitary adenoma.
Abstract: Binding studies of [3H]-spiroperidol, a potent dopamine antagonist, were performed on dispersed cells obtained from 2 mixed PRL- and GH-secreting adenomas, 3 GH-secreting adenomas and 4 ‘no
TL;DR: The low plasma levels of adrenal androgens sometimes seen in GH-deficient patients are not due to the absence of GH per se, and the low plasma concentrations of DHEA-S and the urinary 17-KS and free cortisol levels were unchanged, indicating that a role for hGH in the physiologic control of Adrenal androgen secretion is not substantiated.
Abstract: The effect of human growth hormone (hGH) on adrenal androgen secretion was assessed in 7 patients (5 males, 2 females) with GH deficiency but normal ACTH-cortisol function. Patients ranged in age from
TL;DR: It is indicated that hCG therapy alone can induce and maintain spermatogenesis in some patients with complete hypogonadotropic hypog ongonadism.
Abstract: The effect of long-term hCG administration on sperm output was evaluated in a study in 3 hypogonadal patients with a selective deficiency of gonadotrophins (LH and FSH). The diagnosis of complete hypo
TL;DR: In dams which had been kept isolated from pups for 8-10 h, the magnitude of the suckling-induced prolactin rise in the plasma was studied in relation to intensity of suckling stimulus and lactational age of the mother.
Abstract: In dams which had been kept isolated from pups for 8–10 h, the magnitude of the suckling-induced prolactin rise in the plasma was studied in relation to intensity of suckling stimulus and lactational
TL;DR: Measurements of serum gonadotropins and plasma androgens in the authors' patients show that abnormal sexual development in patients with Fanconi's anemia is due to hypergonadotropic hypogonadism.
Abstract: 2 siblings with Fanconi’s anemia, 1 male and 1 female, aged 22 and 24 years, respectively, were evaluated at the Johns Hopkins Hospital because of short stature and hypogonadism. Plasma levels of soma
TL;DR: The effects of substance P, angiotensin II, oxotremorine and prostaglandin D2 (PG D2) on thyrotropin-releasing hormone (TRH) and thyrotopin (TSH) secretion in rats were studied and the inhibitory effect of SP on TSH release was prevented.
Abstract: The effects of substance P (SP), angiotensin II, oxotremorine and prostaglandin D2 (PG D2) on thyrotropin-releasing hormone (TRH) and thyrotropin (TSH) secretion in rats were studied. Either SP (100 µg/kg), angiotensin II (500 µg/kg), oxotremorine (1.0 mg/kg) or PGD2 (500 µg/kg) was injected intravenously or intraperitoneally, and the rats were serially decapitated. TRH, TSH and thyroid hormone were measured by means of a specific radioimmunoassay for each. The hypothalamic immunoreactive TRH (ir-TRH) contents were significantly increased by oxotremorine or SP and significantly decreased by angiotensin II, but no by PG D2. The plasma ir-TRH concentrations were significantly increased by angiotensin II, but not by oxotremorine, SP or PG D2. The plasma TSH levels were significantly increased by angiotensin II and significantly decreased by oxotremorine, SP or PG D2 in a dose-related manner. The plasma ir-TRH and TSH responses to cold were inhibited by oxotremorine, SP or PG D2, but enhanced by angiotensin II. The plasma TSH response to TRH was inhibited by SP, but enhanced by angiotensin II. The plasma TSH response to TRH did not differ from that of the control after PG D2 injection. In the haloperidol- or para-chlorophenylalanine (PCPA)-pretreated group, the inhibitory effect of PG D2 or oxotremorine on TSH release was prevented, while in the L-DOPA- or 5-hydroxytryptophan (5-HTP)-pretreated group, the inhibitory effect of SP on TSH release was prevented. In the haloperidol- or 5-HTP-pretreated group, the stimulatory effect of angiotensin II on TSH release was prevented. These drugs alone did not affect plasma TSH levels in terms of the dose used. The plasma thyroid hormone levels were not changed by SP, oxotremorine, angiotensin II or PG D2. The inactivation of TRH immunoreactivity by hypothalamus or plasma in vitro after these injections did not differ from that of the control. These findings suggest that oxotremorine and PG D2 act at the hypothalamus level by inhibiting TRH release, and that SP acts both on the hypothalamus and the pituitary to inhibit TRH and TSH release; angiotensin II, on the other hand, acts both at the hypothalamus and the pituitary levels to stimulate TRH and TSH release, and all of these effects are at least partially modified by amines of the central nervous system.
TL;DR: The results suggest that some of the reported beneficial effects of bromocriptine in acromegaly may be independent of GH secretion or somatomedin generation.
Abstract: Clinical and hormonal responses to bromocriptine therapy were assessed in 10 patients with acromegaly. Although substantial falls (≧ 50%) in serum GH occurred in only 4 of the patients, subjective cli
TL;DR: The relationship between the pineal gland and testes of the toad was investigated in breeding and hibernating seasons and it is speculated that the cyclic pineal activity might be responsible for the seasonal variation of spermatogenesis in the toads.
Abstract: The relationship between the pineal gland and testes of the toad was investigated in breeding and hibernating seasons. Pinealectomy increased spermatogenesis in hibernating toads but it failed to exert any effect during the breeding season. The pineals were found to be active during hibernation and atrophied in the breeding season. It is speculated that the cyclic pineal activity might be responsible for the seasonal variation of spermatogenesis in the toad.
TL;DR: The data suggests that elevated TRH in primary hypothyroid subjects may act directly as a nonosmotic stimulus or modulate the osmoreceptor and hypothalamic neurohypophyseal system for AVP release.
Abstract: Effect of thyrotropic releasing hormone (TRH) on plasma arginine vasopressin (AVP) was studied in human subjects. All 7 normal controls and 2 hypothyrotropic hypothyroid subjects failed to show any rise of AVP on TRH administration. The 4 primary hypothyroid subjects had elevated basal AVP level and showed further elevation on TRH administration. Our data suggests that elevated TRH in primary hypothyroid subjects may act directly as a nonosmotic stimulus or modulate the osmoreceptor and hypothalamic neurohypophyseal system for AVP release.
TL;DR: The results suggest that the in vivo uptake of hCG in the testes is modulated by the hormone dose used and that the mode of early serum testosterone response to varying hCG doses is dose dependent.
Abstract: The in vivo uptake of human chorionic gonadotropin (hCG) in the rat testes and mode of the early testosterone response were studied after a single intravenous injection of varying doses of hCG. The up
TL;DR: There was a good correlation between weight-for-height and SM-act during the first two hGH doses, which fits the hypothesis of GH and insulin synergism on SM generation.
Abstract: 15 prepubertal children with short stature and varying peak growth hormone (GH) levels were given daily injections of increasing doses of human growth hormone (hGH) for consecutive periods of 7 days. Somatomedin activity (SM-act) and total urinary hydroxyproline excretion (THP) were determined in each period. In patients with a varying degree of GH deficiency, but without non-pituitary dependent abnormalities, there was a high correlation between basal SM-act and height velocity. Patients with catch-up growth had an unproportionally low SM-act and the Prader-Willi and transient Cushing patients had an unproportionally high one. All patients showed increases of SM-act and THP on hGH administration, but there was considerable variation of the shape of the curve and of the amplitude of the response. 3½ days after the last injection, SM-act was back to basal level. There was a good correlation between weight-for-height and SM-act during the first two hGH doses, which fits the hypothesis of GH and insulin synergism on SM generation.
TL;DR: The clonidine-induced inhibition of corticosterone after alpha-methyl-p-tyrosine seems to be mediated by alpha-adrenoceptors located postsynaptically, which supports the concept of the noradrenergic inhibition of ACTH secretion in rats.
Abstract: In conscious, nonstressed rats clonidine given intracerebroventricularly (i.c.v.) increased the pituitary-adrenocortical response evaluated indirectly from corticosterone concentration. The maximum significant increase occurred 60 min after a dose of 10 micrograms. The alpha 2-adrenoceptor antagonist yohimbine given alone i.c.v. in low doses (0.05-1 microgram) had no effect on plasma corticosterone levels, but at higher doses (5 and 10 micrograms) it produced a significant rise in these levels. Phenoxybenzamine (0.05-10 micrograms, i.c.v.) caused a dose-related increase in corticosterone secretion. Pretreatment of rats with yohimbine considerably antagonized (up to 70%) the increase of corticosterone response induced by clonidine. Phenoxybenzamine failed to alter this effect. The depletion of brain catecholamines by alpha-methyl-p-tyrosine caused an increase in serum corticosterone concentration. The rise was suppressed by clonidine (10 micrograms, i.c.v.), and this suppression was antagonized in part by pretreatment with yohimbine. These data support the concept of the noradrenergic inhibition of ACTH secretion in rats. It seems likely that clonidine injected i.c.v. induces stimulation of corticosterone through the activation of presynaptic alpha 2-adrenoceptors and inhibition of noradrenaline release. The clonidine-induced inhibition of corticosterone after alpha-methyl-p-tyrosine seems to be mediated by alpha-adrenoceptors located postsynaptically.