Immunocytological identification of two cell types in the intermediate lobe of the hypophysis of salmonids: presence of ACTH and alpha-MSH]

The lead-haematoxylin positive cells (PbH+) of the rostral pars distalis react with antibodies anti-1-24 ACTH and anti-17-39 ACTH; the pars intermedia (PI) is composed of two cell categories, but only one is revealed with cyto-immunological techniques and contains ACTH and alpha-MSH in several Salmonid species.     

Antigenic determinants of beta-LPH, beta-MSH, alpha-endorphin, ACTH and alpha-MSH revealed by anti-beta-endorphin in neurons of the human infundibular nucleus]

Comparison of adjacent serial sections of the tubero-infundibular region of Human adult hypothalamus demonstrates that the same perikarya, axons and terminals are stained both with anti-beta-endorphin and anti 17-39 ACTH antisera. The most immunoreactive of these neurons are also revealed with anti alpha-endorphin, anti alpha and beta-MSH, anti-1-24 ACTH and anti beta-LPH. These results suggest that neurons of the infundibular nucleus can store and probably secrete peptide similar to propiocortin or fragment(s) of this molecule.     

New histochemical contributions to the study of corticotropic cells in the adenohypophysis of the chick enbryo.]

Comparative analysis of results obtained after subsequent treatments of chick embryo adenohypophysis by anti-ACTH 17-39 Is, PAS and Bodian method demonstrates that ACTH cells are PAS positive, Bodian negative and are located in the cephalic lobe. With the histochemical fluorescence method of Falck, the cells marked by anti-ACTH 17-39 Is exhibit an induced fluorescence, after L-DOPA injection. However, after treatment by metopirone, numerous cells of the caudal part of the adenohypophysis take up L-DOPA but they are not corticotrophs.     

Immunofluorescence identification of cells with corticotropic and alpha-melanotropic activity in the hypophysis of the grass snake Natrix natrix L.]

The use of anti ACTH (17-39) and alpha-MSH allowed us to detect by immunofluorescence in the Pituitary gland of Grass Snake the site of elaboration of ACTH and alpha-MSH. Corticotropic cells are located in the rostral part of the Pars Distalis and in the Pars intermedia. Melanotropic cells occupy the whole part of the Pars intermedia.     

Cytoimmunological study of the corticotrophic and corticomelanotrophic cells in the adenohypophysis of Boops salpa L. (marine teleost) in different experimental conditions (variation of salinity and of background color)]

The cytoimmunological study of the adenohypophysis of Boops salpa (marine Teleost), in different experimental conditions confirmed that the MacConaill's hematoxyline-positive cells contain: 1. ACTH (Corticotrophic Hormone) in the pars distalis, 2. MSH (Melanocyte-Stimulating Hormone) and ACTH in the pars intermedia.     

Age-and sex-related development of ACTH in the pars distalis and neurointermedia of rat pituitary]

The content of ACTH of the pars distalis and neurointermedia of the pituitary of adult Rats is higher in the male than in the female. This differenciation of content, according to sex, appears at puberty at the site of pars distalis; it only appears around the 60th day of life at the site of the pars intermedia. The androgens seem to be responsible for the higher percentages observed in the males.     

Immunocytological localization of peptide analogs of alpha-endorphin in several neurons of the lateral nucleus tuberis of Carassius auratus L. and Cyprinus carpio L.]

Neurons of the pars lateralis of the N.L.T. of Carassius auratus and Cyprinus carpio display a positive immunocytological reaction with an anti alpha-endorphin serum. It is assumed that the peptides produced by these neurons are similar, if not identical, with alpha-endorphin, but their morphinomimetic properties have still to be established. Peptides of this kind may participate in the regulation of pituitary functions.     

Ultrastructure of neurons of nucleus preopticus and pars lateralis of the nucleus lateralis tuberis in Gambusia (Teleosta poeciliidae)]

The nucleus preopticus (NPO) and the pars lateralis of the nucleus lateralis tuberis (NLT) have been examined at the ultrastructural level. In the NPO two types of large neurons occur, both containing 140-150 nm secretory granules. The pars lateralis of the NLT contains only one cell type with similar granules. Both of these nuclei may be the source of type A fibres innervating the gonadotropic cells of Gambusia.     

Activation of the pituitary-adrenal axis by nipple suction in the lactating rat]

The response of the pituitary-adrenal axis to suckling in lactating Rats is dependent on two factors: 1. a psychic factor, which is identical by its effects to the psychological stress of the strange environment (transitory increase of plasma corticosterone and no significant modification of the content of ACTH in the two lobes of the pituitary); 2. a specific factor namely the stimulation of the nipples, which is distinguishable from the psychic factor by a longer release of corticosterone by the adrenals and a durable and significant decrease of the content of ACTH in the pars distalis.     

Immunohistochemical study of the pars intermediate of the mouse pituitary in different experimental conditions.

Alpha-MSH, beta-MSH and ACTH have been localized in the cells of hypophyseal intermediate lobe by fluorescence histoimmunological technics. Elaboration and excretion of these polypeptides are enhanced after dehydration or adrenalectomy. The most evident variations are seen with alpha-MSH and ACTH after dehydration, with beta-MSH after adrenalectomy.     

Immunofluorencence localization of secretions related to gonadotropic, corticotropic, melanotropic and somatotropic hormones in hypophysis of Nectophrynoides occidentalis]

In Nectophryno?des occidentalis, ovine anti-LH anti beta (1-24) corticotropin, both anti alpha and anti beta MSH and bovine anti-STH antisera allowed us to identify by immunofluorescence gonadotropic, corticotropic, melanotropic and somatotropic hypophysial cells of a viviparous toad. The identification of these different cell types was confirmed by applying a classical cytologic technique to the same sections.     

Immunofluorescent localization of beta-lipotropin (beta-LPH) and beta-endorphins in normal and anencephalic human fetal pituitary gland]

The use of antibodies to alpha-(17-39) ACTH, beta-LPH, alpha- and beta-endorphins has enabled the detection of immunoreactive cells in human fetal pituitary glands as early as the eight week of gestation. The same cells reacted with the different antibodies. Immunoreactive cells were also observed in the pituitary of 6 human anencephalic fetuses.     

Interaction between fluorescent-labeled ACTH1-24, isolated fat cells, and serum albumin

Part of all of the difference in the ability of ACTH1-24, and a fluorescent-labeled ACTH1-24 to activate lipolysis in fat cells can be accounted for by label-related binding to albumin present in the assay medium.     

Occurrence of aldehyde-fuchsin and performic acid-victoria blue positive granules in the ovarian pedicle ofDysdercus koenigii F. (Pyrrhocridae: Heteroptera)

Summary A cycle of activity of aldehyde-fuchsin and performic acid-Victoria blue positive granules was observed in the ovarian pedicle ofDysdercus koenigii during the first ovipositional cycle. The quantitative variation of these granules in the pedicle can also be correlated directly with the increase or decrease of the neurosecretory material in the A-type cells of the pars intercerebralis medialis region of the protocerebrum of the brain.The authors are grateful to Director of Research, University of Udaipur, Udaipur (Rajasthan), for providing laboratory facilities.     

Hyperglycemic effect in the rabbit induced by ACTH4-10

In the rabbit, a single i.v. administration of ACTH4-10 (130 micrograms/kg) induces hyperglycemia. As ACTH4-10 also induces hypocalcemia and inhibits insulin secretion, we suggest that hypocalcemia, inhibition of insulin secretion, and hyperglycemia, are closely related.     

Occurance of aldehyde-fuchsin and performic acid-victoria blue positive granules in the ovarian pedicle of Dysdercus koenigii F. (Pyrrhocridae: Heteroptera).

A cycle of activity of aldehyde-fuchsin and performic acid-Victoria blue positive granules was observed in the ovarian pedicle of Dysdercus koenigii during the first ovipositional cycle. The quantitative variation of these granules in the pedicle can also be correlated directly with the increase or decrease of the neurosecretory material in the A-type cells of the pars intercerebralis medialis region of the protocerebrum of the brian.     

Location of allatostatic centers in the pars lateralis regions of the brain of the Colorado potato beetle

Summary Selective lesions in the pars intercerebralis and pars lateralis areas of the brain of the adult Colorado potato beetle were produced by radiofrequency cautery. The effect of these lesions on the corpus allatum activity, determined by the short-term in vitro radiochemical assay, revealed that gland inhibitory centers are located in the pars lateralis.     

Role of adenosine A1 and A2 receptors in the regulation of aldosterone production in rat adrenal glands

To investigate the roles of adenosine A1 and A2 receptors in the regulation of aldosterone production, we examined the effects of adenosine and adenosine agonists (N6-cyclohexyl adenosine; selective adenosine A1 receptor agonist and 5'-N-ethylcarboxamine adenosine; selective adenosine A2 receptor agonist) on aldosterone and cyclic AMP production in rat adrenal capsular cells. Neither adenosine nor 5'-N-ethylcarboxamine adenosine caused significant effects on basal aldosterone or cyclic AMP production. Also, adenosine (10(-3) M) showed no consistent effects on aldosterone and cyclic AMP production induced by ACTH. On the other hand, N6-cyclohexyl adenosine exhibited a significant inhibition of basal aldosterone and cyclic AMP production at doses of 10(-4) M and 10(-3) M; furthermore, 10(-3) M N6-cyclohexyl adenosine inhibited aldosterone and cyclic AMP production stimulated by ACTH. These results suggest that adenosine A1 receptors are coupled to and inhibit adenylate cyclase and may be involved in the inhibition of aldosterone production.