Browse more peptide research, methods and limitations.
SQ 28603 potentiated both ANP effects in monkeys (increased plasma ANP, sodium excretion) and BNP effects in hypertensive rats (blood pressure lowering, renal responses).
Seymour, A A; Abboa-Offei, B E; Smith, P L; Mathers, P D; Asaad, M M; Rogers, W L · Animal Study
N- or C-terminus modified dynorphin and beta-endorphin selectively blocked excitatory opioid receptor functions, dramatically enhancing the pain-relieving effects of opioid agonists.
Shen, K F; Crain, S M · In Vitro
DSIP administration produced marked changes in substance P, beta-endorphin, and corticosterone levels in both the hypothalamus and blood plasma. These changes persisted at both 1 hour and 24 hours after injection, indicating a prolonged cascade of molecular effects. The response pattern differed between Wistar rats and August rats — two strains with different baseline resistance to emotional stress. DSIP stimulated stress-resistance mechanisms more strongly in Wistar rats than in August rats, which are already more stress-resistant.
Sudakov, K V; Coghlan, J P; Kotov, A V; Salieva, R M; Polyntsev YuV; Koplik, E V ·
Beta-endorphin in the MPOA dose-dependently impaired male rat sexual behavior, prevented by naloxone, while other opioid peptides were less effective at equivalent doses.
van Furth, W R; van Emst, M G; van Ree, J M · Animal Study
Phorbol ester induced a concentration- and time-dependent increase in prodynorphin mRNA in cardiac myocytes, peaking at 4 hours and mediated through protein kinase C.
Ventura, C; Pintus, G; Vaona, I; Bennardini, F; Pinna, G; Tadolini, B · In Vitro
IGF-1 had a half-life of only 2 minutes in the duodenum and ileum, but casein protein significantly protected it from degradation in the gut.
Xian, C J; Shoubridge, C A; Read, L C · Animal Study
Fulminant hepatic failure significantly altered Met-enkephalin, Leu-enkephalin, dynorphin A, and beta-endorphin levels in multiple brain regions and plasma.
Yurdaydin, C; Li, Y; Ha, J H; Jones, E A; Rothman, R; Basile, A S · Animal Study
Opioid peptide levels in respiratory brainstem regions change significantly between young and older piglets, and prenatal cocaine exposure disrupts this developmental pattern.
Zhang, C; Moss, I R · Animal Study
Dynorphin peptides activate a cloned orphan receptor with high sequence homology to opioid receptors, functioning as its endogenous ligands via G protein-coupled potassium channel activation.
Zhang, S; Yu, L · In Vitro
GHRP-2 was considerably more potent than GHRP-6 at stimulating GH release through PKC-dependent pathways, and both caused crosstalk with the cAMP pathway in gsp oncogene-expressing tumors.
Adams, E F; Lei, T; Buchfelder, M; Bowers, C Y; Fahlbusch, R · In Vitro
GHRPs stimulate growth hormone release through a receptor distinct from GHRH, acting at both the pituitary and hypothalamic level, with consistent effects demonstrated across species and administration routes.
Argente, J; García-Segura, L M; Pozo, J; Chowen, J A · Review
Three CRF receptor subtypes (CRF1, CRF2alpha, CRF2beta) and a CRF-binding protein coordinate stress responses, and newly developed non-peptide CRF antagonists show therapeutic promise.
Behan, D P; Grigoriadis, D E; Lovenberg, T; Chalmers, D; Heinrichs, S; Liaw, C; De Souza, E B · Review
Endogenous opioid peptides in cerebral perivascular nerves and CSF actively regulate cerebral blood flow through opiate receptors, with concentrations changing in response to perfusion pressure and oxygen tension.
Benyó, Z; Wahl, M · Review
Multiple gastrointestinal peptide hormone levels were significantly altered during acute hepatic cytonecrosis and returned toward normal during liver regeneration.
Budillon, G; Cuomo, R; Taccone, W; Panico, G; Pumpo, R; Iaquinto, G; Manzillo, G · Cross Sectional
Daily oral MK-677 significantly stimulated the GH-IGF-1 axis in healthy elderly adults aged 64-81, raising levels toward those seen in younger individuals.
Chapman, I M; Bach, M A; Van Cauter, E; Farmer, M; Krupa, D; Taylor, A M; Schilling, L M; Cole, K Y; Skiles, E H; Pezzoli, S S; Hartman, M L; Veldhuis, J D; Gormley, G J; Thorner, M O · RCT
Bedtime MK-677 at 25 mg for 7 days significantly increased 24-hour GH profiles and IGF-1 in young men without altering adrenocortical function.
Copinschi, G; Van Onderbergen, A; L'Hermite-Balériaux, M; Mendel, C M; Caufriez, A; Leproult, R; Bolognese, J A; De Smet, M; Thorner, M O; Van Cauter, E · RCT
Cecropin B was the most potent antimicrobial peptide against B. pertussis, with cecropins generally outperforming magainins, defensins, and protamine.
Fernandez, R C; Weiss, A A · In Vitro
ANP, BNP, and cGMP were compared as screening markers for asymptomatic and symptomatic left ventricular dysfunction, with potential utility for early detection.
Friedl, W; Mair, J; Thomas, S; Pichler, M; Puschendorf, B · Cross Sectional
Antimicrobial peptide effectiveness against Brucella abortus depended significantly on bacterial surface structure, with rough mutants showing different susceptibility patterns than smooth strains.
Halling, S M · In Vitro
Plasma adrenomedullin concentrations were extremely elevated in septic ICU patients compared to healthy controls, correlating with disease severity.
Hirata, Y; Mitaka, C; Sato, K; Nagura, T; Tsunoda, Y; Amaha, K; Marumo, F · Cross Sectional
Conditioned enhancement of NK cell activity depends on mu-opioid receptor activation, with beta-endorphin and met-enkephalin as the key mediating peptides.
Hsueh, C M; Chen, S F; Huang, H J; Ghanta, V K; Hiramoto, R N · Animal Study
Chronic intracerebroventricular beta-endorphin infusion significantly enhanced in vivo NK cell cytotoxicity and altered splenic and peripheral blood lymphocyte phenotypes.
Jonsdottir, I H; Johansson, C; Asea, A; Hellstrand, K; Thorén, P; Hoffmann, P · Animal Study
KP-102 induces c-fos expression specifically in the arcuate nucleus, and this occurs even in hypophysectomized rats, confirming a direct hypothalamic site of action.
Kamegai, J; Hasegawa, O; Minami, S; Sugihara, H; Wakabayashi, I · Animal Study
Hexarelin maintained GH-releasing efficacy with repeated administration, and hexarelin plus GHRH produced a synergistic GH response exceeding individual effects.
Massoud, A F; Hindmarsh, P C; Matthews, D R; Brook, C G · RCT
NPY mediates analgesia and hyperalgesia through distinct receptor subtypes, alongside established roles in blood pressure regulation and anxiety modulation.
Munglani, R; Hudspith, M J; Hunt, S P · Review
Orphanin FQ/nociceptin suppressed dopamine release in the nucleus accumbens, acting opposite to classical opioids which typically increase dopamine in this reward-related region.
Murphy, N P; Ly, H T; Maidment, N T · Animal Study
Mu, delta, and kappa opioid receptors in cardiac sarcolemma activate pertussis toxin-sensitive G proteins and inhibit adenylyl cyclase, confirming a complete opioid signaling pathway in the heart.
Niroomand, F; Mura, R A; Piacentini, L; Kübler, W · In Vitro
Plasma BNP may increase proportionally more than ANP after acute myocardial infarction and chronic heart failure, potentially offering superior diagnostic and prognostic value.
Omland, T; Aakvaag, A; Bonarjee, V V; Caidahl, K; Lie, R T; Nilsen, D W; Sundsfjord, J A; Dickstein, K · Cohort
Pardaxin possesses high antibacterial activity, and engineered variants achieved potent bacterial killing while reducing harmful effects on mammalian cells.
Oren, Z; Shai, Y · In Vitro
Endogenous opioid peptides contribute to post-tetanic inhibition of gut muscle contractions, and peptidase inhibitors enhance this effect by protecting naturally released peptides from degradation.
Ozaki, M; Masuda, Y; Yamamoto, H · In Vitro
The GH secretagogue receptor was solubilized as a ~255 kDa receptor-ligand-G-protein complex from porcine pituitary, confirming it is distinct from the GHRH receptor.
Pomés, A; Pong, S S; Schaeffer, J M · In Vitro
A specific high-affinity G-protein-linked receptor for GH secretagogues was identified, operating through a distinct signaling pathway from GHRH.
Pong, S S; Chaung, L Y; Dean, D C; Nargund, R P; Patchett, A A; Smith, R G · In Vitro
Combination thymosin alpha-1 (1 mg twice weekly) and lymphoblastoid interferon was tested as a strategy to improve sustained response rates in chronic hepatitis C over interferon monotherapy.
Rasi, G; DiVirgilio, D; Mutchnick, M G; Colella, F; Sinibaldi-Vallebona, P; Pierimarchi, P; Valli, B; Garaci, E · RCT
BPC-157 provided strong gastroprotection against four distinct injury types (stress, ethanol, NSAID, capsaicin neurotoxicity), suggesting a broad protective mechanism involving sensory nerve pathways.
Sikirić, P; Seiwerth, S; Grabarević, Z; Rucman, R; Petek, M; Jagić, V; Turković, B; Rotkvić, I; Mise, S; Zoricić, I; Gjurasin, M; Konjevoda, P; Separović, J; Ljubanović, D; Artuković, B; Bratulić, M; Tisljar, M; Jurina, L; Buljat, G; Miklić, P; Marović, A · Animal Study
BPC-157 demonstrated both prophylactic and therapeutic effects in bile duct ligation-induced pancreatitis, also improving concomitant gastric and duodenal lesions.
Sikirić, P; Seiwerth, S; Grabarević, Z; Rucman, R; Petek, M; Jagić, V; Turković, B; Rotkvić, I; Mise, S; Zoricić, I; Jurina, L; Konjevoda, P; Hanzevacki, M; Ljubanović, D; Separović, J; Gjurasin, M; Bratulić, M; Artuković, B; Jelovac, N; Buljat, G · Animal Study
Proenkephalin-derived peptides increase hippocampal excitability via mu/delta receptors, while prodynorphin-derived peptides decrease it via kappa receptors, providing opposing regulation of memory circuits.
Simmons, M L; Chavkin, C · Review
GH secretagogues act through a novel receptor at dual sites (hypothalamus and pituitary) to amplify natural pulsatile GH release rather than creating continuous artificial elevation.
Smith, R G; Pong, S S; Hickey, G; Jacks, T; Cheng, K; Leonard, R; Cohen, C J; Arena, J P; Chang, C H; Drisko, J; Wyvratt, M; Fisher, M; Nargund, R; Patchett, A · Review
Approximately 40% of cardiac ganglion cells contained dynorphin A immunoreactivity, and opioid peptides were found in parasympathetic, sympathetic, and sensory cardiac nerves.
Steele, P A; Aromataris, E C; Riederer, B M · Animal Study
Peptidase inhibitors significantly prolonged the antinociceptive effect of intrathecally administered dynorphin A (0.5-2 nmol) and dynorphin B (2-8 nmol) in the formalin test.
Tan-No, K; Taira, A; Sakurada, T; Inoue, M; Sakurada, S; Tadano, T; Sato, T; Sakurada, C; Nylander, I; Silberring, J; Terenius, L; Kisara, K · Animal Study
GHRP-2 maintained GH-releasing efficacy in critically ill patients despite blunted responses to GHRH, suggesting a preserved alternative pathway for GH stimulation.
Van den Berghe, G; de Zegher, F; Bowers, C Y; Wouters, P; Muller, P; Soetens, F; Vlasselaers, D; Schetz, M; Verwaest, C; Lauwers, P; Bouillon, R · RCT
NEP inhibition with thiorphan significantly potentiated the blood pressure-lowering, hormonal, and renal effects of all three natriuretic peptides (ANP, BNP, CNP) in hypertensive transgenic rats.
Wegner, M; Ganten, D; Stasch, J P · Animal Study
NEP activity is increased in volume-overload heart failure, potentially accelerating the breakdown of protective natriuretic peptides even as the heart produces more of them.
Wegner, M; Hirth-Dietrich, C; Stasch, J P · Animal Study
Ad libitum access to a high-fat/sucrose diet significantly increased hypothalamic dynorphin peptide and mRNA levels compared to standard diet, suggesting opioid peptide-mediated overeating.
Welch, C C; Kim, E M; Grace, M K; Billington, C J; Levine, A S · Animal Study
GHRP-2 increased intracellular cAMP (like GHRH) while GHRP-6 released GH without raising cAMP, revealing partially different mechanisms despite similar GH-releasing outcomes.
Wu, D; Chen, C; Zhang, J; Bowers, C Y; Clarke, I J · In Vitro
BNP was superior to both C-terminal ANP and N-terminal ANP for detecting left ventricular systolic dysfunction, diastolic dysfunction, and ventricular hypertrophy.
Yamamoto, K; Burnett, J C; Jougasaki, M; Nishimura, R A; Bailey, K R; Saito, Y; Nakao, K; Redfield, M M · Cross Sectional
GHRP-2 and hexarelin both showed potent GH-releasing activity with slight stimulatory effects on prolactin, ACTH, and cortisol; their GH-releasing activities were directly compared for the first time.
Arvat, E; di Vito, L; Maccagno, B; Broglio, F; Boghen, M F; Deghenghi, R; Camanni, F; Ghigo, E · RCT
GHRP-2 stimulation revealed significant residual GH secretory potential in children classified as GH-deficient, with peak responses varying by growth disorder type.
Bercu, B B; Walker, R F · Clinical Trial
Antimicrobial peptide effectiveness against mollicutes varied dramatically by species, with animal defense peptides being less potent than venom and bacterial peptides. Multiple cellular effects preceded killing.
Béven, L; Wróblewski, H · In Vitro
Oral MK-677 stimulated GH and IGF-I in selected severely GH-deficient adults, with responses dependent on residual pituitary secretory capacity.
Chapman, I M; Pescovitz, O H; Murphy, G; Treep, T; Cerchio, K A; Krupa, D; Gertz, B; Polvino, W J; Skiles, E H; Pezzoli, S S; Thorner, M O · RCT
GHRP-2 and GHRP-6 each synergize with GRF/GHRH but combining both GHRPs at maximal doses adds no further GH release, confirming shared receptor competition.
Cheng, J; Wu, T J; Butler, B; Cheng, K · In Vitro