A superactive antinociceptive pentapeptide, (D‐Met<sup>2</sup>,Pro<sup>5</sup>)‐enkephalinamide

Bajusz, S.; Rónai, András Z.; Székely, József I.; Gráf, László; Dunai-Kovács, Zsuzsa; Berzétei, I.

doi:10.1016/0014-5793(77)80127-0

Cited by 151 publications

(19 citation statements)

References 8 publications

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“…The syntheses of compounds I-V have been reported in [2,3]. CD measurements were performed at room temperature on a Jobin-Yvon-Roussell-Jouan model III dichrograph using spectral grade acetonitrile (AN), double-distilled water and analytical reagent grade salts.…”

Section: Methodsmentioning

confidence: 99%

“…Recently some Pros-analogs of Met/Leu'-enkephalin [l] containing a D-amino acid residue in position 2 have been synthesized [2,3]. Of these analogs,(D-Met', Pro')-enkephalinamide (V, table 1) proved to be one of the most active analgesic of peptide nature [3].…”

Section: Introductionmentioning

confidence: 99%

“…Of these analogs,(D-Met', Pro')-enkephalinamide (V, table 1) proved to be one of the most active analgesic of peptide nature [3]. According to more recent in vitro data, its effect is also influenced by Mn" [4].…”

Section: Introductionmentioning

confidence: 99%

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CD studies on enkephalin and its Pro⁵‐analogs

Hollósi

Dobolyi

Bajusz³

1980

FEBS Letters

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Section: Methodsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

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CD studies on enkephalin and its Pro⁵‐analogs

Hollósi

Dobolyi

Bajusz³

1980

FEBS Letters

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“…Among these synthetized analogs, it is noteworthy that (Pro)' analogs are the most active compounds, especially when the second amino acid is also replaced by either D-Ala or D-Met [3,4]; these last substitutions strongly decrease the metabolic deactivation induced by various peptidases [7,8]. However, the exceptional nature of proline, that is an amino acid in which the amine function is intracyclic, could possibly explain this high morphinomimetic activity.…”

Section: Introductionmentioning

confidence: 99%

(D‐Ala², N‐Val⁵) enkephalinamide and (D‐Met², N‐Val)⁵ enkephalinamide

1980

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“…A potent enkephalin analogue, (D-Met2, Pro5)-enkephalinamidt.. synthesized by Bajusz et al (22) and already used in our previous investigations (1 5,[23][24][25][26][27], and the opiate antagonist naloxone, have been injected into ten different regions of the brain of conscious male rats and their acute effect on plasma PRL. GH, LH, follicle-stimulating hormone (FSH) and ACTH tested.…”

mentioning

confidence: 99%

Central Nervous System Sites of Action of an Enkephalin Analogue, (D‐Met², Pro⁵)‐Enkephalinamide, and Naloxone on the Secretion of Five Anterior Pituitary Hormones of Male Rats

Molnár

Marton

Halász

1990

J Neuroendocrinology

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Central nervous system sites of action of opioid peptides on pituitary hormone secretion were investigated. One nmol of an enkephalin analogue, (D-Met', Pros)-enkephalinamide, and 10 nmol of the opiate antagonist naloxone were injected into ten different regions of the brain of conscious male rats and their effect on the release of five anterior pituitary hormones tested. The injections were made through a special injection cannula which was inserted into the brain through a guide cannula fixed on the skull and implanted into the brain 5 to 7 days earlier. Both compounds injected into the medial septum, medial preoptic area and hypothalamic paraventricular nucleus affected prolactin, growth hormone and luteinizing hormone (LH) secretion. The enkephalin analogue stimulated prolactin and growth hormone and inhibited LH release. Naloxone induced the opposite effect. Drugs given into the hypothalamic ventromedial nucleus caused changes in plasma prolactin and growth hormone levels. Enkephalinamide increased and naloxone decreased plasma concentrations of both hormones. Administration of the compounds into the dorsal raphe area resulted in alterations of prolactin and LH release, the analogue caused elevation of prolactin and inhibition of LH release, whereas the opiate antagonist resulted in opposite changes. Only an LH response was obtained from the hypothalamic dorsomedial nucleus and a growth hormone response from the central amygdala. Also in these cases the enkephalin analogue decreased LH and elevated growth hormone plasma levels, and naloxone brought about a rise in LH and a diminution of growth hormone concentration. None of the regions were effective in inducing a clear-cut adrenocorticotrophin or follicle-stimulating hormone response. The parietal cortex, medial amygdala and the dentate gyrus were entirely ineffective sites. The findings suggest that in the brain there are multiple sites of action of opioids on pituitary trophic hormone secretion and the effective sites are not identical in terms of pituitary hormone response.4 large number of experimental data indicate (1-5) that opioid peptides affect secretion of pituitary trophic hormones. In general, it appears that they stimulate prolactin (PRL) and growth hormone (GH), inhibit the release of gonadotrophins, primarily of luteinizing hormone (LH), and elevate or depress plasma adrenocorticotrophin (ACTH) and thyrotroph hormone levels. These effects can be counteracted by the opiate antagonist naloxone. Although there are some observations indicating a direct action of opioid peptides on the anterior pituitary (6-9), most of the findings suggest that they may exert their influence via the CNS (10-13). Such a view is consistent with the presence of all three families of endogenous opioid peptides (proopiomelanocortin-derived endorphins, enkephalins and dynorphins) and opioid peptide receptors in the brain. The observations that opiate antagonists or opiate receptor blockcrs cause alterations in pituitary trophic hormone secretion suggest that en...

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A superactive antinociceptive pentapeptide, (D‐Met²,Pro⁵)‐enkephalinamide

Cited by 151 publications

References 8 publications

CD studies on enkephalin and its Pro⁵‐analogs

CD studies on enkephalin and its Pro⁵‐analogs

(D‐Ala², N‐Val⁵) enkephalinamide and (D‐Met², N‐Val)⁵ enkephalinamide

Central Nervous System Sites of Action of an Enkephalin Analogue, (D‐Met², Pro⁵)‐Enkephalinamide, and Naloxone on the Secretion of Five Anterior Pituitary Hormones of Male Rats

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A superactive antinociceptive pentapeptide, (D‐Met2,Pro5)‐enkephalinamide

Cited by 151 publications

References 8 publications

CD studies on enkephalin and its Pro5‐analogs

CD studies on enkephalin and its Pro5‐analogs

(D‐Ala2, N‐Val5) enkephalinamide and (D‐Met2, N‐Val)5 enkephalinamide

Central Nervous System Sites of Action of an Enkephalin Analogue, (D‐Met2, Pro5)‐Enkephalinamide, and Naloxone on the Secretion of Five Anterior Pituitary Hormones of Male Rats

Contact Info

Product

Resources

About

A superactive antinociceptive pentapeptide, (D‐Met²,Pro⁵)‐enkephalinamide

CD studies on enkephalin and its Pro⁵‐analogs

CD studies on enkephalin and its Pro⁵‐analogs

(D‐Ala², N‐Val⁵) enkephalinamide and (D‐Met², N‐Val)⁵ enkephalinamide

Central Nervous System Sites of Action of an Enkephalin Analogue, (D‐Met², Pro⁵)‐Enkephalinamide, and Naloxone on the Secretion of Five Anterior Pituitary Hormones of Male Rats