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Madalyn Butcher

Bio: Madalyn Butcher is an academic researcher from Salk Institute for Biological Studies. The author has contributed to research in topics: Somatostatin & Hypothalamus. The author has an hindex of 5, co-authored 6 publications receiving 3923 citations.

Papers
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Journal ArticleDOI
05 Jan 1973-Science
TL;DR: A peptide has been isolated from ovine hypothalamus which, at 1 x 10-9M, inhibits secretion in vitro of immunoreactive rat or human growth hormones and is similarly active in vivo in rats.
Abstract: A peptide has been isolated from ovine hypothalamus which, at 1 x 10(-9)M, inhibits secretion in vitro of immunoreactive rat or human growth hormones and is similarly active in vivo in rats. Its structure is H-Ala-Gly-Cys-Lys-Asn-Phe-Phe-Trp-Lys-Thr-Phe-Thr-Ser-Cys-OH The synthetic replicate is biologically active.

3,383 citations

Journal ArticleDOI
TL;DR: The primary structure of ovine hypothalamic hypophysiotropic luteinizing hormone-releasing factor, LRF, has been established as pGlu-His-Trp-Ser-Tyr-Gly-Leu-Arg-Pro-Gel-NH(2) by hydrolysis of the peptide with chymotrypsin or pyrrolidone-carboxylylpeptidase and by analysis of the products by
Abstract: The primary structure of ovine hypothalamic hypophysiotropic luteinizing hormone-releasing factor, LRF, has been established as pGlu-His-Trp-Ser-Tyr-Gly-Leu-Arg-Pro-Gly-NH2 by hydrolysis of the peptide with chymotrypsin or pyrrolidone-carboxylylpeptidase and by analysis of the products by an Edman-dansylation sequencing technique, as well as by mass spectrometry of the derived phenylthiohydantoins. A decapeptide with the proposed primary structure, prepared by total synthesis, gave the same result on sequencing. The synthetic decapeptide possesses the same biological activities as the native ovine LRF. The amino-acid sequence of ovine LRF is identical to that already published for porcine LRF.

436 citations

Journal ArticleDOI
TL;DR: Somatostatin, a peptide isolated from ovine hypothalamic tissue that inhibits the release of radioimmunoassayable growth hormone in vitro from rat or human pituitary cells or in vivo in rats, has the primary structure.
Abstract: Somatostatin, a peptide isolated from ovine hypothalamic tissue that inhibits the release of radioimmunoassayable growth hormone in vitro from rat or human pituitary cells or in vivo in rats, has the primary structure [Formula: see text]. The structure was established by submitting the carboxymethylated peptide, the carboxymethylated tryptic digest, and the chymotryptic digest of the peptide to Edman degradation. Degradation products were analyzed by amino-acid analysis, as well as in some cases by determination of N-termini by dansylation or by determination of phenylthiohydantoins by mass spectrometry.

178 citations

Journal ArticleDOI
TL;DR: Myelin basic protein is to be recognized as a potentially interfering substance in any search for the physiological growth hormone releasing factor using in vitro assay systems.

11 citations

01 Jan 1972
TL;DR: The primarystructure of ovinehypo- thalamic hypophysiotropic luteinizing hormone-releasing factor, LRF, has been established by hydrolysis of the pep- tidewithchymotrypsin orpyrrolidone-earboxylylpepti- dase and byanalysis of the products by anEdman-dansyl- ationsequencing technique.
Abstract: The primarystructure of ovinehypo- thalamic hypophysiotropic luteinizing hormone-releasing factor, LRF,hasbeenestablished aspGlu-His-Trp-Ser- Tyr-Gly-Leu-Arg-Pro-Gly-NH2 by hydrolysis ofthepep- tidewithchymotrypsin orpyrrolidone-earboxylylpepti- daseandbyanalysis oftheproducts byanEdman-dansyl- ationsequencing technique, aswellasbymassspectrome- tryofthederivedphenylthiohydantoins. A decapeptide withtheproposedprimarystructure, preparedby total synthesis, gavethesameresult onsequencing. Thesyn- thetic decapeptide possesses thesamebiological activities asthenative ovineLRF.Theamino-acid sequence ofovine LRF isidentical tothatalready published forporcine LRF. Various areas ofthecentral nervous system participate inthe fine regulation ofthesecretion ofalladenohypophysial hor- mones. Theultimate integrator ofinformation originating in thecentral nervous systemisthehypothalamus. Thefinal information fromthehypothalamus totheadenohypophysis isnottransmitted intheformofnerveimpulses, butiscar- ried intheformofspecific hypothalamic hypophysiotropic substances, thehypothalamic releasing factors, thatarecar- ried through thehypothalamo-hypophysial portal system of capillaries fromthemedian eminence region oftheventral hypothalamus tothecells oftheadenohypophysis. Thereis goodphysiological evidence thatsuchahypothalamic control isinvolved inthesecretion ofthegonadotropin, luteinizing hormone. Intheearly 1960s, several investigators reported experimental results that werebest explained byproposing the existence ofsubstances thatspecifically stimulated thesecre- tionofluteinizing hormone, andthatwereprobably polypep- tides, incrude aqueous extracts ofhypothalamic tissues of various mammalian species (1-3). Preparations ofLRF,active at1/Ag perdoseinanimal bioassays, wereobtained bygel filtration andion-exchange chromatography on carboxy- methylcellulose (4), anobservation thatwasconfirmed by similar methods byseveral investigators (5,6).Inspite of thevagaries ofthevarious bioassay methods available, several laboratories reported preparations ofLRF ofincreased po- tency(5, 6). Several ofthese early publications ledtocontra- dictory statements regarding purification andseparation of LH-releasing factor (LRF), froma follicle-stimula ting hor-

5 citations


Cited by
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Journal ArticleDOI
05 Jan 1973-Science
TL;DR: A peptide has been isolated from ovine hypothalamus which, at 1 x 10-9M, inhibits secretion in vitro of immunoreactive rat or human growth hormones and is similarly active in vivo in rats.
Abstract: A peptide has been isolated from ovine hypothalamus which, at 1 x 10(-9)M, inhibits secretion in vitro of immunoreactive rat or human growth hormones and is similarly active in vivo in rats. Its structure is H-Ala-Gly-Cys-Lys-Asn-Phe-Phe-Trp-Lys-Thr-Phe-Thr-Ser-Cys-OH The synthetic replicate is biologically active.

3,383 citations

Journal ArticleDOI
TL;DR: The purpose of this review is to provide a comprehensive survey of the current understanding of prolactin's function and its regulation and to expose some of the controversies still existing.
Abstract: Prolactin is a protein hormone of the anterior pituitary gland that was originally named for its ability to promote lactation in response to the suckling stimulus of hungry young mammals. We now know that prolactin is not as simple as originally described. Indeed, chemically, prolactin appears in a multiplicity of posttranslational forms ranging from size variants to chemical modifications such as phosphorylation or glycosylation. It is not only synthesized in the pituitary gland, as originally described, but also within the central nervous system, the immune system, the uterus and its associated tissues of conception, and even the mammary gland itself. Moreover, its biological actions are not limited solely to reproduction because it has been shown to control a variety of behaviors and even play a role in homeostasis. Prolactin-releasing stimuli not only include the nursing stimulus, but light, audition, olfaction, and stress can serve a stimulatory role. Finally, although it is well known that dopamine of hypothalamic origin provides inhibitory control over the secretion of prolactin, other factors within the brain, pituitary gland, and peripheral organs have been shown to inhibit or stimulate prolactin secretion as well. It is the purpose of this review to provide a comprehensive survey of our current understanding of prolactin's function and its regulation and to expose some of the controversies still existing.

2,193 citations

Book ChapterDOI
TL;DR: The aim of this chapter is to examine structural and functional roles of turns in peptides and proteins.
Abstract: Publisher Summary Turns are a fundamental class of polypeptide structure and are defined as sites where the peptide chain reverses its overall direction. In the past 20 years, the peptide field has witnessed major development, stimulated by the discovery of a host of bioactive peptides. Turn structures have been proposed and implicated in the bioactivity of several of these naturally occurring peptides. In addition, many structural details of turns have been derived from conformational studies of model peptides. During this same period, more than 100 complete protein structures have been elucidated in single-crystal X-ray studies. These examples document the rich diversity of structural patterns in the chain folds of native proteins. Turns are intrinsically polar structures with backbone groups that pack together closely and side chains that project outward. Such an array of atoms may constitute a site for molecular recognition, and indeed, the literature abounds with suggestions that turns serve as loci for receptor binding, antibody recognition, and post-translational modification. In peptides, turns are the conformations of choice for simultaneously optimizing both backbone–chain compactness (intramolecular nonbonded contacts) and side-chain clustering (to facilitate intermolecular recognition). Presence of turns in bioactive conformations may in fact also reflect the lack of alternative conformational possibilities. The aim of this chapter is to examine structural and functional roles of turns in peptides and proteins.

1,580 citations

Journal ArticleDOI
TL;DR: Among the wide spectrum of SST effects, several biological responses have been identified that display absolute or relative subtype selectivity and selected nonpeptide agonists with nanomolar affinity have been developed.

1,557 citations

Journal ArticleDOI
TL;DR: Your contributions to the investigation of this tragic disorder are presented and a review of current ideas about the disease is reviewed.
Abstract: Huntington9s disease (HD) is an autosomal dominant disorder of midlife onset, characterized by progressive involuntary choreiform movements, psychologic change, and dementia. In 1980, funded by the NINCDS, we established a center for the study of HD. This report presents a summary of our contributions to the investigation of this tragic disorder and a review of current ideas about the disease.

1,400 citations