The CRF neuron: immunocytochemical study.

In the central nervous systems of several species belonging to different vertebrate classes, immunocytochemical stainings with an antiserum to ovine CRF 41 show multiple location of CRF perikarya and various areas containing CRF fibres and terminals. These stainings reflect species and interspecies functional adaptations of the CRF neurones which constitute a prominent hypothalamo-infundibular system involved in pituitary gland control, and also interneurone systems as attested to by extrahypothalamic perikarya and by CRF perisomatal endings in several brain areas. Perikarya of the hypothalamo-infundibular system are mainly packed in the paraventricular nucleus (mammals, birds) or in homologous areas, e.g.: paraventricular organ (turtle) where they are CSF-contacting neurones and preoptic nucleus (amphibians, fishes). In all species but fish, CRF fibres end in the median eminence (ME) against portal vessels. In fish, CRF processes terminate in the peripheral areas of proadenohypophyseal neurodigitations, close to corticotrophs. In all species these stainings are abolished by preabsorption of the serum by CRF. In fishes, reptiles and amphibians they are also suppressed by urotensin I, which is thought to be the teleost's CRF. Adrenalectomy experiments in the rat provided evidence for a corticosteroid regulation of ME CRF: short term (12-24 hr) adrenalectomy induces a complete depletion of CRF immunoreactivity followed by a secondary accumulation (5-20 days). This biphasic evolution is prevented by a dexamethasone replacement therapy. Inhibitory role of catecholamines on CRF release was indicated by: disappearance of ME CRF, induced by a single reserpine injection and suppression of this effect by monoamineoxidase inhibitor (pargyline or tranylcypromine) pretreatment. CRF fibres were first observed in the ME at the 16th week of fetal development in the human, and at the 18th day in the rat fetus. Thus, immunoreactive CRF system develops later than pituitary corticotrophs.

Immunocytochemical demonstration of corticoliberin-like immunoreactivity (CLI) in neurones of the rat amygdala central nucleus (ACN).

Anti-corticotropin-releasing factor (CRF) antibodies revealed numerous perikarya in the amygdala central nucleus (ACN) of colchicine-injected rats. Most of the immunoreactive processes emerging from these neurone bodies seemed to project to the lateral hypothalamus by the ventral amygdalo-hypothalamic pathway. As well as parvocellular areas of the hypothalamic paraventricular nucleus where numerous neurones containing corticoliberin-like immunoreactivity (CLI) were demonstrated, ACN is densely innervated by beta-endorphin fibres originating from pro-opiomelanocortin neurones of the hypothalamic arcuate nucleus. The facilitatory influences of the amygdala on the corticotropic axis are most probably mediated by the ACN CLI neurones, the possible infundibular projections of which remain to be demonstrated.

Changes in corticoliberin and vasopressin-like immunoreactivities in the zona externa of the median eminence in adrenalectomized rats. Immunocytochemical study.

The zona externa of the median eminence was found completely depleted of corticoliberin-like immunoreactivity (CLI) and of vasopressin-like immunoreactivity (VLI) 12-14 h and 22-24 h after bilateral adrenalectomy. Amount of CLI increased to the level of untreated rats 5 days after this operation while amount of VLI rose higher than in control animals. The same was found 20 days after surgery. These results emphasize the involvement of two infundibular neurosecretory systems--CLI and VLI--in the regulation of the pituitary--adrenal axis.

Comparative study of the neuronal populations containing beta-endorphin, corticotropin and dopamine in the arcuate nucleus of the rat hypothalamus.

Neurons simultaneously immunoreactive with anti-beta-endorphin and anti-(17-39) corticotropin (anti(17-39) ACTH) have been detected in the arcuate and ventromedial nuclei of the hypothalamus of colchicine-treated rats. These neurons are different from those fluorescent with the Falck and Hillarp technique. These results show that in the arcuate nucleus, immunoreactive ACTH and beta-endorphine are stored in the same neurons which are different from dopamine-containing neurons.

Immunocytochemical demonstration of a novel peptidergic neurone system in the cat brain with an anti-growth hormone-releasing factor serum.

In 15-day-, 1-month- and 1.5-month- old cats an antiserum against hpGRF-44 stained a novel hypothalamo-infundibular neuroglandular system. Its intra-eminential processes present an important development between 15 and 30 days of age. Perikarya and nerve fibres, which are abundant in several brain areas as early as the 15th day, suggest that the peptide revealed by hpGRF-44 antibodies also acts as a neuromodulator.

Cloning of cDNAs encoding a rat neuropeptide immunologically related to salmon melanin-concentrating hormone.

In order to identify the neuropeptide related to melanin-concentrating hormone (MCH) synthetized by neurons of the posterior hypothalamus in the mammals, we have screened rat hypothalamus and rat brain cDNA expression libraries using MCH antiserum. We isolated 5 distinct immunopositive recombinants with cross-hybridizing cDNA inserts. One of them hybridized to RNAs exclusively located in neurons stained by the same antiserum, as seen by successively performing in situ hybridization and then an immunocytochemical technique on the same section. Sequencing of this MCH-like cDNA is in progress.

[Organotypic culture of human corneal epithelium. Preliminary results]. / Culture organotypique d'épithélium cornéen humain. Résultats préliminaires.

The authors compared the growth of limbal and central explants removed from human cornea. Epithelial growth began on the third day, was greater during the first week and was subsequently slightly invaded by fibroblasts. This study demonstrated that peripheral corneal epithelial cells growth better than central cells. In this study, the cytologic and histologic features of the cells were examined. However, epithelial immunofluorescence staining by anti-cytokeratin antibodies was rather poor. This in vitro system may provide a suitable model for epithelial human corneal cell culture, allowing further biocompatibility studies.

[Contribution of immunocytochemistry to the study of the development of neuroglandular peptidergic systems in the human fetal hypothalamus]. / Apport de l'immunocytochimie à l'étude du développement de systèmes neuroglandulaires peptidergiques dans l'hypothalamus foetal humain.

Immunohistochemistry makes possible the in situ detection of neuropeptides in the cell bodies were they are synthesized, in the fibers that carry them, and in endings. Immunohistochemistry appears necessary to identify and map peptidergic neurons and to study their ontogeny. From 1975, we have carried the immunohistochemical study of several hypothalamic neuronal populations in the human fetus: LH-RH (1976), somatostatin (1977), pro-opiocortin (1978), vasopressin and oxytocin (1979), corticoliberin (1982), somatocrinin (1983), and hypothalamic neurons containing an unidentified peptide (1984). Comparative ontogenetical studies have also been performed in rats.

[Cytoimmunological and histochemical study of cat adenohypophyseal cells, made fluorescent by the Falck and Hillarp technic]. / Etude cyto-immunologique et histochimique des cellules rendues fluorescentes par la technique de Falck et Hillarp dans l'adénohypophyse du chat

In the Cat, after Falck and Hillarp method, all the fluorescent cells of the PI and the anterior lobe of adenohypophysis can be revealed with specific anti-sera to ACTH(1-24), ACTH(17-39), bovine beta-MSH and porcine beta-LPH. With the lead hematoxyline staining method, two types of cells are recognizable in the anterior lobe, in which the non hormonal constituents of the granules must be different.

[Immunocytochemical detection of the CRF-containing neurons in the rat brain (author's transl)]. / Mise en évidence immunocytochimique du système neuroglandulaire à-CRF dans l'hypothalamus du rat.

Immunocytochemical studies on Rat brains using an antiserum against CRF revealed a new hypothalamo-infundibular neuroglandular system: its perikarya are mainly located in the paraventricular nucleus; its nerve endings are very numerous around the blood vessels in all region of the external zone of the median eminence and in the periphery of the pituitary stalk.

[Corticoliberin neurons in the rat brain]. / Les neurones à corticolibérine (CRF) du cerveau de rat.

A new peptidergic paraventriculo-infundibular system has been revealed using anti-corticoliberin (CRF) antibodies. The localization of its perikarya in the paraventricular nuclei as well as the distribution of its fibres and perivascular nerve-endings within the median eminence are different from those of other systems stained with antibodies directed against gonadoliberin, somatostatin, vasopressin or oxytocin.

[Ontogenesis of pro-opio-melano-cortin neurons in the rat]. / Ontogenèse des neurones à pro-opio-mélano-cortine chez le rat.

Immunocytochemical study of the pro-opio-melano-cortin neurones in rat fetuses and newborns indicates that: 1) they appear precociously in the mediobasal hypothalamus, as early as day 13 of fetal development, that is to say 3 days before pro-opio-melano-cortin-containing pituitary cells; 2) between day 13 and day 17 they display synchronous changes in their intracellular patterns of immunoreactivity, arguing in favour of their cyclic secreting activity, which precedes the establishing of their projections; 3) beginning with day 18 until birth, the somatal immunoreactivity disappears transitorily; during the same period and the first postnatal days, their immunoreactive fibres extend in various brain regions.

[Immunocytochemical study of the ontogenesis of the CRF-containing neuroglandular system in the rat (author's transl)]. / Etude immunocytochimique de l'ontogenèse du système neuroglandulaire à CRF chez le rat.

In the Rat, immunoreactive CRF-containing processes appear in the median eminence between the 18 and the 19th day of the fetal development. They seem to become functional as early as the 19th day since they establish neuro-hemal junctions with the capillaries of the Mantel Plexus. During the pre- and post-natal periods, the number of these fibers increases greatly in the median eminence where they extend in all parts of the zona externa, and in the pituitary stalk. At birth they display a biphasic evolution made up of a disappearance of the corticoliberin immunoreactivity followed by an accumulation accompanied by the appearance of a few immunoreactive perikarya in the paraventricular nucleus.

[Comparative study in the guinea pig, cat and dog of hypothalamo-infundibular nervous fibers immunoreactive to an anti-LH-RH immune serum]. / Etude comparative chez le cobaye, le chat et le chien, des fibres nerveuses hypothalamo-infundibulaires immunoréactives à un immun-sérum anti-LH-RH

In the median eminence of guinea pig, cat and dog some axons of the hypothalamo-infundibular tract are immunoreactive with anti LH-RH. In these three species, the axons have a similar topography and area of peripheric terminations. These one occur at the capillaries of Mantelplexus. It was also shown, in the cat, that these areas of termination exhibit a strong monoamine fluorescence.

[Demonstration of a neuronal peptide system reactive with anti-CRF41 immune serum, in fresh water and marine teleosts]. / Mise en évidence d'un système neuronal peptidergique réactif à un immun-serum anti-CRF41, chez les téléostéens dulcicoles et marins.

CRF41 antibodies stained a peptidergic neurone system in the brain of several species of Teleost Fish. Perikarya are localized in the preoptic nucleus. Processes terminate mainly in the neurodigitations of the proadenohypophysis, close to corticotrophs. There are fewer ending in the neural lobe in contact with pars intermedia cells. CRF +/- nerve profiles and perisomatal endings were also observed in various brain areas.

Pallister Killian--mosaic tetrasomy 12 p syndrome. Another prenatally diagnosed case.

A new case of mosaic tetrasomy 12 p (46,XY/47,XY, +i12 p), diagnosed during pregnancy from ultrasonographic signs, is reported. We emphasize the peculiar position of the diaphragmatic hernia in this syndrome. Its presence or absence determines the vital prognosis and the age of diagnosis. The knowledge of its possible association with tetrasomy 12 p can contribute considerably to the neonatal diagnosis by directing the work of the cytogeneticist to tissue cultures which enable him to detect the presence of the tetrasomy.

[Immunocytologic analysis, in rat hypothalamus, of neurons producing peptides related to endorphin, ACTH, MSH and beta-LPH. Comparison with other peptidergic and monoaminergic neurons]. / Analyse immunocytologique, dans l'hypothalamus du rat, des neurones producteurs de peptides de type endorphine. ACTH, MSH et beta-LPH. Etude comparative avec d'autres neurones peptidergiques et monoaminergiques.

In rat hypothalamus intraventricularly injected with colchicine, the same neurons of the ventral region are stained with I.S. against alpha and beta-endorphin, (1-24) and (17-39) ACTH, alpha and beta-MSH, and beta-LPH. They are distinct from those producing LH-RH, somatostatin, neurophysin, and dopamine. These results suggest that the same neurons elaborate peptides identical with or immunologically related to endorphins, ACTH, alpha-MSH and beta-LPH, probably issued from a common precursor.

Neurons of the rat hypothalamus reactive with antisera against endorphins, ACTH, MSH and beta-LPH.

In rat brains intraventricularly injected with colchicine, the same discrete neurons of the arcuate and ventromedial nuclei can be stained with antisera against alpha- and beta-endorphins, (1-24)ACTH, (17-39)ACTH, alpha- and beta-MSH, and beta-LPH, as demonstrated by comparative studies in consecutive serial sections. These neurons are strongly reactive with anti-(17-39)ACTH, anti-beta-endorphin, anti-alpha-MSH and anti-beta-MSH, and more faintly stained with anti-alpha-endorphin, anti-beta-LPH and anti-(1-24)ACTH. Exceptionally, neurons reactive with anti-(17-39)ACTH and anti-beta-endorphin are poorly stained or completely negative with anti-alpha-MSH and anti-beta-MSH. Immunoreactive fibers end in the lateral median eminence and in the arcuate nucleus proper, or form ascending pathways along the third ventricle. Comparative studies with other antisera or with the Falck and Hillarp technique show that these neurons differ from the elements producing LH-RH, somatostatin, neurophysin, oxytocin, vasopressin and dopamine. These results suggest that the same neurons of the rat hypothalamus synthesize several neuropeptides identical with or immunologically related to endorphins, ACTH, alpha-MSH and beta-LPH, probably arising from a common precursor molecule similar to that found in the corticotropic cells of the pituitary. These neuropeptides of a common cellular and molecular origin might be involved in basic processes of the central nervous system as neurotramsmitters or neuromodulators.