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C Girod

Publications and source records attributed to C Girod.

At least 55 records · Page 3Linked to original sources
PubMed1986

Ultrastructural observations on folliculo-stellate cells in the pars distalis of the pituitary gland in three rodent species.

Ultrastructural features of folliculo-stellate cells of the anterior lobe of the pituitary gland were described in three rodent species (the mouse, guinea pig, golden hamster). These cells are agranular and form the lining of tiny follicles projecting microvilli. Long cytoplasmic expanding processes are intermingled with granular cells of various morphofunctional types without special relationships to one cell type or another. In the guinea pig, the abundance of intermediate filaments appears as a notable feature in the cytoplasm of the folliculo-stellate cells. The results are compared with those previously published.

Actin Cytoskeleton↗
PubMed1986

The human gonadotropic adenoma: pathologic diagnosis and hormonal correlations in 26 tumors.

Twenty-six out of 400 surgically removed pituitary tumors were identified as gonadotropic adenomas (frequency 6.25%). Morphologic, immunocytochemical, and hormonal characteristics of the gonadotropic adenoma are described. The following morphologic characteristics may suggest the diagnosis: arrangement in cords of cells showing signs of cellular activity, secretory granules, which vary in electron density, form, and size (mean diameter 150 nm) and which are numerous in the extensions near the capillaries, and a rough endoplasmic reticulum arranged in short cisternae. However, owing to the morphofunctional variations from one adenoma to another, we consider that only immunoreactivity with gonadotropin antisera proves the diagnosis. Because the material used to generate the gonadotropin antisera was purified but not pure, for precise characterization of the immunoreactivity, absorption tests with various antigens have to be performed. FSH-LH adenomas (n = 14), FSH adenomas (n = 7), and alpha-subunit adenomas (n = 5) but no LH adenomas were identified in our series. No evident morphologic difference related to the type of immunoreactivity and to the sex was found. Almost all the tumors were large with visual signs caused by suprasellar extension. A recurrence following adenomectomy was noted with a frequency of 12%. The diagnosis of gonadotropic adenoma was considered preoperatively in six out of 26 patients only, on the basis of increased serum gonadotropin levels. Correlations between hormonal levels and pathologic data were established in 17 patients. Seven tumors were associated with high serum gonadotropin levels (FSH and LH: three patients and FSH alone: four patients). In ten cases, the serum gonadotropin levels were normal but serum alpha-subunit assay had not been performed. For the pathologist systematically testing the adenomas with many antisera, gonadotropic adenomas are not as rare as for the clinician. Immunocytochemical studies with gonadotropin antisera and serum gonadotropic determination must be performed in all tumors, especially in those pituitary adenomas that appear nonfunctional.

Adenoma↗
PubMed1986

The human thyrotropic adenoma: pathologic diagnosis in five cases and critical review of the literature.

Five out of 400 surgically removed pituitary tumors (frequency: 1.2%) were identified as thyrotropic adenomas according to the following criteria: identification of tumoral thyrotropic cells by immunocytochemistry and ultrastructural study; elevated serum TSH levels with decrease after surgery; and elevated concentration of TSH in the tumor. Four patients presented with hyperthyroidism and one with euthyroidism. From these five cases and 11 similar observations extracted from a critical review of literature, the morphologic, immunocytochemical, and hormonal characteristics of thyrotropic adenoma are described. Thyrotropic adenomas are more often large tumors but may also be microadenomas. The diagnosis is asserted by immunoreactivity with anti-TSH antisera. The TSH positive tumor cells are numerous. In some tumors, rare cells of other types are also found (PRL, GH, FSH, or ACTH cells). Some morphologic characteristics strongly suggest the diagnosis. The cells are often large with thin processes. They show argyrophil granulations in a slightly basophil cytoplasm and signs of secretory activity. Their secretory granules are round and small without striking variations in size, shape, and electron density. Elevated concentration of TSH in the tumor confirms the diagnosis. The presence of high serum TSH levels and a molar ratio of alpha hTSH to the whole TSH molecule greater than one are other good criteria. Decrease of TSH after surgery may not be observed in invasive tumors. TSH adenoma is most often associated with hyperthyroidism but it can also be associated with hypothyroidism or euthyroidism.

Adenoma↗
PubMed1986

Cell types of the pars distalis of the hedgehog (Erinaceus europaeus L.) adenohypophysis: cytological, immunocytochemical and ultrastructural studies. 4. Thyrotropic cells.

Staining and histochemical methods, immunofluorescence and electron microscopy were used to individualize the thyrotropic cells in the adenohypophysis of the non-hibernating hedgehog. One cell type was differentiated; its characteristics at the light and electron-microscopic levels were presented. Immunofluorescence has confirmed the functional significance of this cell type and the validity of the denomination of 'thyrotropic cells'.

Animals↗
PubMed1986

Ultrastructural identification of folliculo-stellate cells in the pars distalis of the cat and dog pituitary gland.

Ultrastructural features of folliculo-stellate cells of the anterior lobe of the pituitary gland have been described in the cat and dog. These cells are agranular and form the lining of tiny follicles into which microvilli project. Long expanding cytoplasmic processes are intermingled with granular cells of various types without special relationships to one cell type or another. A few features are reported which are peculiar to each species. The results are compared with those previously described.

Animals↗
PubMed1986

Role of portasystemic shunts in the hyperkinetic circulation of the portal hypertensive rat.

We evaluated the role of portasystemic shunts in the hyperkinetic circulatory state in rats with portal hypertension. Cardiac output and regional blood flow were measured by the radioactive microsphere technique in rats with portal hypertension caused by portal vein stenosis, in rats with end-to-side portacaval shunts, and in sham-operated rats. Cardiac output was significantly higher in rats with surgical shunts than in those of the two other groups and was significantly lower in sham-operated rats compared with portal hypertensive rats. Portal tributary blood flow and hepatic arterial blood flow expressed in absolute flow as well as in percentage of cardiac output were significantly increased in rats with surgical shunts compared with other groups. These blood flows were also significantly higher in portal hypertensive rats than in sham-operated animals. A significant correlation was found between cardiac output and portal tributary blood flow in rats with portal vein stenosis and in rats with surgical shunts; this correlation was absent in sham-operated rats. This study shows that the hyperkinetic circulatory state in rats with portal hypertension and a normal liver is related to the presence of portasystemic shunts but not to portal hypertension per se.

Animals↗
PubMed1985

[Endocrine pancreatic tumor secreting somatostatin and somatocrinin].

A case of endocrine pancreatic tumour secreting the 2 antagonistic peptides that regulate growth hormone, somatostatin and somatocrinin, is reported. Such tumours are extremely rare and only one other case has been published so far, although pancreatic malignant tumours frequently secrete several hormones. In our patient, the association of diabetes with steatorrhoea, hypochlorhydria, anaemia and biliary lithiasis suggested hypersecretion of somatostatin. Acromegaly, suggested by clinical signs, was confirmed by an excess of growth hormone and somatomedin, and pre-operative somatrocrinin assay confirmed its extra-pituitary origin. Finally, the presence of hyperparathyroidism due to parathyroid gland hyperplasia and of a Recklinghausen disease constituted a multiple endocrine neoplasia syndrome. The significance and implications of this double secretion in vivo are discussed.

Adenoma, Islet Cell↗
PubMed1985

Immunocytochemical localization of S-100 protein in interstitial cells of the monkey Macaca irus pineal gland.

Pineal interstitial cells of the monkey Macaca irus were shown to react with an anti-human S-100 protein antibody, using the indirect immunoperoxidase technique on sections of paraplast-embedded pineal glands. Immunoreactivity was seen in the cytoplasm of the cells, stellate in shape and intermingled with pinealocytes; the latter did not stain with the antiserum against S-100 protein. Immunoreactivity was also present in the nuclei, as was reported in various other cell types immunostained with anti-S-100 protein antibodies. The present results support the view that interstitial cells of the monkey Macaca irus pineal gland may be of astroglial origin.

Animals↗
PubMed1985

Immunocytochemical localization of S-100 protein in stellate cells (folliculo-stellate cells) of the anterior lobe of the normal human pituitary.

With the use of an anti-human S-100 protein antibody, it was possible to reveal a characteristic cell type in the anterior lobe of the normal human pituitary. These cells, so-called folliculo-stellate cells, were present in all pituitaries studied but their number varied from one gland to another. Immunoreactive cells, isolated or grouped, were arranged close to various secretory granulated cells. Especially by use of double immunoenzymatic labeling, it was evident that these cells are spatially related either to somatotropes, prolactin cells and "corticotropes", or to glycoprotein-containing cells. Such immunoreactive cells were rare or absent in pseudo-follicular arrangements of secretory granulated cells. Since it is now possible to identify this cell type by light microscopy and since no reliable functional significance is known, it seems more advisable to term this cell type "stellate cell" instead of "folliculo-stellate cell".

Adult↗
PubMed1985

Acute effect of propranolol on splanchnic circulation in normal and portal hypertensive rats.

Propranolol decreases portal venous pressure in patients with cirrhosis but no method is available in man to study the effect of this beta-blocker on splanchnic organ blood flow. Because in rats, the microsphere method allows evaluation of regional blood flow, the acute effect of propranolol on both splanchnic and systemic circulations was studied in normal rats and in rats with portal hypertension due to portal vein stenosis. Portal venous pressure significantly decreased during propranolol administration in normal (5.6 +/- 1.0-4.7 +/- 1.1 mm Hg; mean +/- SD) as well as in portal hypertensive rats (11.7 +/- 2.3-10.3 +/- 1.8 mm Hg). Propranolol slightly decreased cardiac output and arterial pressure in all rats. Portal tributary blood flow was significantly reduced by propranolol in normal rats (17.4 +/- 3.0-11.3 +/- 2.2 ml/min) and in portal hypertensive rats (23.7 +/- 5.0-16.6 +/- 3.3 ml/min). Accordingly vascular resistance of the different organs in the portal venous territory increased in these rats receiving propranolol. The percentage of the decrease in portal tributary blood flow was significantly more marked than the percentage of reduction in cardiac output in portal hypertensive rats but, in normal rats, these percentages were parallel. Hepatic arterial blood flow did not change or slightly increased and, consequently, hepatic arterial vascular resistance decreased. These findings further clarify the marked effects of propranolol on splanchnic circulation.

Animals↗
PubMed1985

Effects of pentobarbital sodium anesthesia on splanchnic hemodynamics of normal and portal-hypertensive rats.

To determine the effect of pentobarbital sodium anesthesia on the rat with portal hypertension due to portal vein stenosis, four groups of rats were studied. Cardiac output and regional blood flow were measured by radioactive microspheres in anesthetized and conscious sham-operated and portal-hypertensive rats. Anesthesia markedly decreased cardiac output in both sham-operated (109.7 +/- 4.6 vs. 77.8 +/- 1.4 ml/min, P less than 0.001) and portal-hypertensive rats (130.1 +/- 7.6 vs. 93.8 +/- 5.3 ml/min, P less than 0.01). In spite of this diminution in cardiac output, pentobarbital did not significantly change absolute blood flow values of splanchnic organs in either group. However, the fractions of cardiac output perfusing the splanchnic organs were significantly increased by pentobarbital in both groups because of the decrease in cardiac output: sham operated, anesthetized, 22.86 +/- 1.19% vs. conscious, 14.83 +/- 1.02%, P less than 0.001; and portal hypertensive, anesthetized, 26.67 +/- 0.71% vs. conscious, 19.07 +/- 1.44%, P less than 0.001. The hyperdynamic circulation of the portal vein-stenosed rat compared with the sham-operated rat continued to manifest itself with significantly increased portal pressure, cardiac output, and splanchnic blood flow, whether the animal was anesthetized or awake. We conclude that, despite marked hemodynamic changes induced by pentobarbital, the rat with portal vein stenosis remains a useful experimental model of portal hypertension.

Anesthesia, General↗
PubMed1985

Somatotropic adenoma manifested by galactorrhea without acromegaly.

In two of eight premenopausal women with somatotropic adenomas, galactorrhea was the earliest clinical feature, associated in one patient with amenorrhea. These two patients did not have clinically evident acromegaly. Mean basal serum GH levels were elevated and did not decrease after glucose ingestion. Both patients had modest hyperprolactinemia. Histological and immunocytological studies of the adenomas showed numerous adenomatous somatotropic cells and some alpha-subunit- and PRL-containing cells. In these patients, the origin of the hyperprolactinemia was not clear. In one patient, elevated GH secretion was probably responsible for the galactorrhea, since it disappeared after surgical treatment despite persistence of hyperprolactinemia. In conclusion, galactorrhea, isolated or associated with amenorrhea, can be the only clinical manifestation of a somatotropic adenoma.

Adenoma↗
PubMed1985

Cell types of the pars distalis of the hedgehog (Erinaceus europaeus L.) adenohypophysis: cytological, immunocytochemical and ultrastructural studies. 3. Opiocorticomelanotropic cells.

Staining and histochemical methods, immunofluorescence and electron microscopy were used to individualize the opiocorticomelanotropic cells in the adenohypophysis of the non-hibernating hedgehog. One cell type was differentiated; its characteristics at the electron-microscopic level were presented. Immunofluorescence has confirmed the functional significance of this cell type and the validity of the denomination 'opiocorticomelanotropic cells'.

Adrenocorticotropic Hormone↗
PubMed1985

[GRF and human somatotropic adenoma. In vivo and in vitro correlations between GH release and morphological and immunocytochemical aspects].

Nine somatotropic adenomas identified by histological and immunocytochemical methods were studied in vitro during 40 days. The spontaneous release of GH decreased at various rates according to adenomas. A decrease in the size, number of secretory granules and in immunoreactivity with anti-hGH serum were also noted. When cortisol was added (350 nM), the GH secretion sustained for a longer time or even increased at its initial level. The effect of GRF (hpGRF1-44NH2, 10(-8)M) on GH release was tested by 3 hours incubation at 6-9 days of culture. The increase in GH varied from 106 to 420% compared to the basal release. It was similar to in vivo release in 3 out of 6 cases. The highest responses were found in densely granulated and strongly immunoreactive adenomas. The effect of GRF on the GH synthesis was studied by continuous incubation of GRF (10(-8)M) from the 10th the 40th day of culture. The quantity of GH in the culture medium was never higher than in culture mediums without GRF. No change in GH concentrations in mediums with or without cortisol was found when TRH (2.5, 10(-6)M) or TRH + GRF was added. No change in morphological and immunocytochemical cell characteristics were noted either with or without GRF. Thus, the variability of GH response to GRF in somatotropic adenomas in culture seems to be related to their morphofunctional heterogeneity. Under our experimental conditions, GRF stimulates the release of stored GH in tumoral cells but does not seem to stimulate its synthesis.

Acromegaly↗