Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P01189 (beta-endorphin)
 21,003 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Adenylate cyclase activity in rabbit adipocyte plasma membranes was studied with special reference to the effects of adrenalectomy and administration of cortisol in vivo. Adrenalectomy was accompanied by an increase in adenylate cyclase activity during basal conditions; cortisol (5 mg/kg body wt., intramuscularly) partly prevents this effect of adrenalectomy. The response of adenylate cyclase to corticotropin, epinephrine and norepinephrine stimulation was higher in the adrenalectomized rabbit than in the sham operated animal. Our in vitro results were in agreement with the striking fat mobilization observed in rabbit plasma after adrenalectomy and with the hypolipemic effects of cortisol we had previously observed in both normal and adrenalectomized rabbit.
Biochim Biophys Acta 1976 Sep 24
PMID:[The effects of adrenalectomy and of hydrocortisone administration on adenylate cyclase activity in rabbit adipose cells (author's transl)]. 18 31

We have studied whether endogenous alpha-MSH has a function in stimulating intra-uterine growth in the rat. The approach used was to determine whether or not this hormone is present during the intra-uterine growth spurt, and if binding of endogenous foetal alpha-MSH by antibodies would inhibit this growth. Antibodies against alpha-MSH or ACTH 1-24, either purified or non-purified, induced immunofluorescence in the intermediate lobe of adult male control rats. Using purified anti-alpha-MSH, fluorescence appeared in the foetal intermediate lobe on day 18 of pregnancy, the day that biologically active MSH was first seen. A negative correlation was observed between the pituitary MSH content and foetal body weight only on day 19 of pregnancy. Injection of purified anti-alpha-MSH induced a drop in foetal body weight, but no effect on placental weight was observed. Purified anti-acth 1-24 had no effect upon body weight but caused an increase in placental weight. These results support our previous findings and indicate that endogenous MSH has a function in the stimulation of foetal growth.
J Endocrinol 1976 Sep
PMID:Stimulation of intra-uterine growth in rat by alpha-melanocyte-stimulating hormone. 18 10

The opiate-like peptide beta-endorphin and adrenocorticotropin are concomitantly secreted in increased amounts by the adenohypophysis in response to acute stress or long-term adrenalectomy as well as in vitro in response to purified corticotropin releasing factor and other secretagogues. Conversely, administration of the synthetic glucocorticoid dexamethasone inhibits the secretion of both adrenocorticotropin and beta-endorphin. Thus, both hormones possess common and identical regulatory mechanisms and there may be a functional role for circulating beta-endorphin.
Science 1977 Sep 30
PMID:beta-Endorphin and adrenocorticotropin are selected concomitantly by the pituitary gland. 19 1

Selective dispersion of melanosomes was often observed after iontophoretic injection of cyclic adenosine monophosphate (AMP) from a glass microelectrode positioned in a target melanophore in frog skin (as viewed from above through a microscope), with other melanophores in the field serving as controls. Because the skin has orderly arrays of several types of closely spaced cells, it is probable that at times the microelectrode also impales cells other than melanophores. When cyclic AMP injection inside a cell resulted in dispersion of melanosomes from a perinuclear position into dendritic processes, the onset of dispersion was relatively rapid, in many cases less than 4 min (mean time of onset, 5.3 +/- 2.9 [SD] min). A much slower dispersion (mean time of onset, 19.0 +/- 5.0 min) of melanosomes was observed when the microelectrode was positioned adjacent to a melanophore, and much larger quantities of cyclic AMP were released. In addition, no changes were observed for injections of 5'-AMP or cyclic guanosine monophosphate (GMP) through electrodes positioned inside or adjacent to melanophores. Potential measurements showed that after impaling a clell, a constant transmembrane potential could often be recorded over many minutes, indicating that the membrane tends to seal around the microelectrode. The results indicate that cyclic AMP acts more rapidly on the inside of a cell than when applied outside a cell and allowed to diffuse through the plasma membrane. This study introduces a model system whereby the properties of the plasma membrane and melanocyte-stimulating hormone (MSH) receptors can be studies within a single target cell.
J Cell Biol 1977 Sep
PMID:Iontophoretic release of cyclic AMP and dispersion of melanosomes within a single melanophore. 19 12

To examine hindbrain pathways mediating release of adrenocorticotropin (ACTH) in response to hemodynamic changes we tested, in 19 cats (chloralose/urethan), 70 neurons in ACTH-active areas of the medulla for their response to volume pulsation (+/- 1 ml, 1 Hz, 60 s) of the right atrium (RA) or to hemorrhage (3 ml/kg per 30 s), and to electrical stimulation in ACTH-active areas of the dorsal rostral pons (DRP). The activity of 16 neurons was increased (P less than 0.05) by RA. Of these, 6 were driven antidromically from the locus subcoeruleus (LSC), and were located in the lateral solitary nucleus and in posteromedial nucleus intercalatus (NI). The activity of 11 neurons was decreased by RA. Of these, 5 were driven antidromically from LSC and lateral ventral tegmental nucleus and were located in anterolateral NI. No rostral projections were found to more medial sites in DRP. Responses to the first trial of RA were rapid, but slowed and attenuated with repeated trials. Responses to hemorrhage were rapid and in the opposite direction, but did not attenuate. The results suggest that pathways displaying rate sensitivity project from the right atrium via B-receptors to the DRP.
Am J Physiol 1977 Sep
PMID:Neurons in medullary areas controlling ACTH: atrial input and rostral projections. 19 72

The relationships among exogenous adrenocorticotropin (ACTH), plasma corticosteroids, and circulating leukocytes were studied in 7 lactating cows. Blood samples were obtained from jugular cannulas at -2, -1, and 0 hours before ACTH was injected (base line) and 0.25, 0.50, 1, 2, 3, 6, and 24 hours after injection. Plasma corticosteroids were increased progressively by injecting doses of ACTH between 1 and 200 IU. Plasma corticosteroids reached peak concentrations between 15 and 30 minutes and returned to base line within 1 to 3 hours after 1, 5, and 10 IU doses of ACTH were injected, but required as long as 6 hours after injection of 100 and 200 IU. Base line counts of circulating leukocytes averaged 7.3 X 10(3) cells/mm3 and remained unchanged after injecting 0 and 1 IU of ACTH (P less than 0.05). Significant dose-dependent increases in circulating leukocytes were detected within 2 hours after administering 5, 10, and 100 IU of ACTH. Responses to 100 and 200 IU were similar. The average concentration of leukocytes increased up to 6 hours after ACTH administration and returned to base line values within 12 to 24 hours in cows injected with 5 and 10 IU, but not until 48 hours in cows injected with 100 and 200 IU of ACTH. In contrast to the delayed and sustained responses observed for leukocytes, corticosteroid responses were rapid and transient. Moreover, the administration of 200 IU of ACTH was considered to increase circulating corticosteroids and leukocytes beyond that found in dairy cattle exposed to stress associated with overmilking, acute coliform mastitis, or parturition.
Am J Vet Res 1977 Sep
PMID:Response of plasma corticosteroids and circulating leukocytes in cattle following intravenous injection of different doses of adrenocorticotropin. 20 Jan 55

1. Avian corticotropin (ACTH) was purified from both fresh and aged pituitary glands of the ostrich Struthio camelus. 2. The isolation of corticotropin in pure form involved acid/acetone extraction, NaCl fractionation, CM-cellulose chromatography and Sephadex G-50 chromatography. 3. The hormone preparations from fresh and aged glands behaved as single substances on polyacrylamide-gel electrophoresis, and both preparations were found to consist of 39 amino acid residues, in identical molar proportions for the different amino acids. 4. The isoelectric points of the two hormone preparations were estimated to be in the range pH 8.3-8.7, indicating possible differences in amide content, and the N-terminal amino acid of both preparations appeared to be serine. 5. The hormone preparations from fresh and aged glands exhibited similar biological potencies (73 and 77 i.u./mg respectively), as measured by steroidogenesis in vitro. 6. Apart from possible differences in amide content, the corticotropin preparations obtained from fresh and aged glands appear to be indistinguishable.
Biochem J 1977 Sep 01
PMID:The isolation and characterization of corticotropin from the pituitary gland of the ostrich Struthio camelus. 20 Feb 25

This study deals with 11 cases of thyroid medullary carcinoma of which 7 were familial cases including 3 cases of Sipple's syndrome and 4 cases of sporadic cases. There were also 2 cases of Cushing's syndrome. In addition to the previously described English literatures about human medullary carcinoma of the thyroid, the rod-shaped body with cristae and an abundant glycogen particles in the cytoplasm, nuclear inclusion bodies of cytoplasmic invagination and microvilli at the surface membrane of gland formation were found in our cases. The mean and mode diameters of secretory granules of all familial cases with only calcitonin secretion were larger than those of the sporadic cases with ectopic ACTH and beta-MSH in addition to calcitonin secretion. Ultrastructural study on non-cancerous follicles of grossly normal thyroid of two cases of early familial medullary carcinoma disclosed apparently increased C-cells which were not intrathyroidal metastases. It is supposed that the increased C-cells in the thyroid of the familial cases are multicentric C-cell hyperplasia.
Acta Pathol Jpn 1977 Sep
PMID:Ultrastructural study of thyroid medullary carcinoma. 20 Nov 48

The ability of melanocyte stimulating hormone (MSH), adrenocorticotropic hormone (ACTH), and prostaglandin E1 (PGE1) to stimulate the accumulation of cyclic AMP was examined in intact mouse melanoma cells of varying metastatic potential. F1 cells (low metastatic potential) had significantly greater cyclic AMP levels in response to all three hormones than F5 (intermediate metastatic potential) and F10 (high metastatic potential) cells. The ranking of the response was as follows: MSH, F1 greater than F5 greater than F10, ACTH, F1 greater than F5 greater F10, PGE, F1 greater than F10 greater F5. In contrast to the above, the degree of hormonal stimulation of adenylate cyclase in broken cell preparations was virtually identical in all three melanoma cell lines. Control enzyme activity was depressed in both F5 and F10 relative to F1. The conflicting results between studies of intact vs. broken cell preparations could not be explained by increased cyclic AMP phosphodiesterase activity in F5 and F10 cells. We conclude that as the melanoma cells increase in metastatic potential, there is a significant loss in the ability of their cyclic AMP system to respond appropriately to hormonal stimuli.
J Cell Physiol 1978 Sep
PMID:Hormonal activation of adenylate cyclase in mouse melanoma metastatic variants. 20 54

GH4C1 cells are a clonal strain of rat pituitary tumor cells which synthesize and secrete prolactin and growth hormone. Somatostatin, a hypothalamic tetradecapeptide, inhibits the release of growth hormone and, under certain circumstances, also prolactin from normal pituitary cells. We have prepared [125I-Tyr1]somatostatin (approximately 2200 C1/mmol) and have shown that this ligand binds to a limited number of high affinity sites on GH4C1 cells. Half-maximal binding of somatostatin occurred at a concentration of 6 x 10(-10) M. A maximum of 0.11 pmol of [125I-Tyr1]somatostatin was bound per mg of cell protein, equivalent to 13,000 receptor sites per cell. The rate constant for binding (kon) was 8 x 10(7) M(-1) min(-1). The rate constant for dissociation (koff) was determined by direct measurement to be 0.02 min(-1) both in the presence and absence of excess nonradioactive somatostatin. Binding of [125I-Tyr1]somatostatin was not inhibited by 10(-7) M thyrotropin-releasing hormones. Substance P, neurotensin, luteinizing hormone-releasing hormone, calcitonin, adrenocorticotropin, or insulin. Of seven nonpituitary cell lines tested, none had specific receptors for somatostatin. Somatostatin was shown to inhibit prolactin and growth hormone production by CH4C1 cells. The dose-response characteristics for binding and the biological actions of somatostatin were essentially coincident. Furthermore, among several clonal pituitary cell strains tested, only those which had receptors for somatostatin showed a biological response to the hormone. We conclude that the characterized somatostatin receptor is necessary for the biological actions of somatostatin on GH4C1 cells.
J Biol Chem 1978 Sep 25
PMID:Characterization of functional receptors for somatostatin in rat pituitary cells in culture. 21 Jan 85


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