Steroidogenic activity of highly potent melanotropic peptides in the adrenal cortex of the rat

1986 ◽  
Vol 113 (3) ◽  
pp. 396-402 ◽  
Author(s):  
J. B. Baumann ◽  
A. N. Eberle ◽  
E. Christen ◽  
W. Ruch ◽  
J. Girard
Keyword(s):  
Adrenal Cortex ◽  
Partial Agonist ◽  
Pigment Cell ◽  
Cell Types ◽  
Activity Profile ◽  
Full Agonist ◽  
Acth Receptor ◽  
Cell Assays ◽  
Isolated Rat

Abstract. Highly purified ACTH and MSH peptides were studied in isolated rat glomerulosa and inner zone cells and their activity compared with that in an Anolis melanophore assay. While both ACTH1-39 and ACTH1-24 were almost equally potent steroidogenic peptides in the two cell types (ED50 between 1 and 4 × 10−12 m), α-MSH displayed only weak steroidogenic activity. Although it was a full agonist, it was about 104-fold less potent in both capsular and inner zone cells. β-MSH (porcine) was even 10-fold less active in capsular cells than α-MSH, and in inner zone cells it was a partial agonist. Highly potent melanotropic peptides, such as (Nle4, D-Phe7)-α-MSH or cyclic (Cys4, Cys10)-α-MSH were either inactive or exhibited only a very slight partial steroidogenic activity in both cell types. Comparison of the activity profile of additional compounds, such as des-acetyl α-MSH, (Tyr(I)2)-α-MSH, (Trp(For)9)-α-MSH or (Nva12-α-MSH in the adrenocortical and pigment cell assays led to the conclusion that α-MSH does not exert its steroidogenic effect through a typical melanocyte-type of MSH receptor, but rather through a low affinity-type of ACTH receptor.

RXR Partial Agonist Produced by Side Chain Repositioning of Alkoxy RXR Full Agonist Retains Antitype 2 Diabetes Activity without the Adverse Effects

2014 ◽  
Vol 58 (2) ◽  
pp. 912-926 ◽  
Author(s):  
Kohei Kawata ◽  
Ken-ichi Morishita ◽  
Mariko Nakayama ◽  
Shoya Yamada ◽  
Toshiki Kobayashi ◽  
...  
Keyword(s):  
Adverse Effects ◽  
Partial Agonist ◽  
Side Chain ◽  
Full Agonist

scholarly journals Simultaneous trimodal single-cell measurement of transcripts, epitopes, and chromatin accessibility using TEA-seq

eLife ◽  
2021 ◽  
Vol 10 ◽  
Author(s):  
Elliott Swanson ◽  
Cara Lord ◽  
Julian Reading ◽  
Alexander T Heubeck ◽  
Palak C Genge ◽  
...  
Keyword(s):  
Gene Regulation ◽  
Single Cell ◽  
Human Peripheral Blood ◽  
Single Cells ◽  
Cell Types ◽  
Chromatin Accessibility ◽  
Specific Gene ◽  
Test Case ◽  
Cell Assays ◽  
Paired Measurement

Single-cell measurements of cellular characteristics have been instrumental in understanding the heterogeneous pathways that drive differentiation, cellular responses to signals, and human disease. Recent advances have allowed paired capture of protein abundance and transcriptomic state, but a lack of epigenetic information in these assays has left a missing link to gene regulation. Using the heterogeneous mixture of cells in human peripheral blood as a test case, we developed a novel scATAC-seq workflow that increases signal-to-noise and allows paired measurement of cell surface markers and chromatin accessibility: integrated cellular indexing of chromatin landscape and epitopes, called ICICLE-seq. We extended this approach using a droplet-based multiomics platform to develop a trimodal assay that simultaneously measures transcriptomics (scRNA-seq), epitopes, and chromatin accessibility (scATAC-seq) from thousands of single cells, which we term TEA-seq. Together, these multimodal single-cell assays provide a novel toolkit to identify type-specific gene regulation and expression grounded in phenotypically defined cell types.

Abecarnil is a Full Agonist at Some, and a Partial Agonist at Other Recombinant GABAA Receptor Subtypes

1993 ◽  
pp. 50-61 ◽  
Author(s):  
I. Pribilla ◽  
R. Neuhaus ◽  
R. Huba ◽  
M. Hillmann ◽  
J. D. Turner ◽  
...  
Keyword(s):  
Gabaa Receptor ◽  
Partial Agonist ◽  
Receptor Subtypes ◽  
Full Agonist ◽  
Gabaa Receptor Subtypes

Role of integrins in melanocyte attachment and dendricity

1994 ◽  
Vol 107 (10) ◽  
pp. 2739-2748 ◽  
Author(s):  
M. Hara ◽  
M. Yaar ◽  
A. Tang ◽  
M.S. Eller ◽  
W. Reenstra ◽  
...  
Keyword(s):  
Flow Cytometry ◽  
Cell Biology ◽  
Type Iv Collagen ◽  
Cell Attachment ◽  
Pigment Cell ◽  
Cell Types ◽  
Dependent Manner ◽  
Flow Cytometry Analysis ◽  
Type Iv ◽  
Alpha V Beta 3

Integrins are a family of proteins known to mediate attachment of cells to extracellular matrix materials. The substratum specificity and cation dependence of specific integrin heterodimers have been extensively characterized, and to a lesser degree specialized roles in cell attachment versus dendricity have been defined in some cell types. In the past decade, melanocyte attachment rate and morphology have been found to have strong substratum dependence, suggesting a major role for integrins in these processes. In order to investigate this aspect of pigment cell biology, human newborn melanocytes were subjected to flow cytometry analysis and plated on a variety of substrata under conditions known to promote or block the binding of specific integrin pairs. Melanocyte attachment to laminin and type IV collagen was promoted by Mg2+ and Mn2+ but not by Ca2+, in the range of concentrations examined. However, dendrite outgrowth from melanocytes already attached on laminin or type IV collagen was promoted by Ca2+ to a far greater degree than by Mg2+, and Mn2+ had no effect on dendrite outgrowth. Flow cytometry analysis revealed that melanocytes expressed beta 1, alpha 2, alpha 3, alpha 5, alpha 6 and alpha v integrin subunits as well as the alpha v beta 3 heterodimer. The influence of substratum on the profile of integrin expression was minimal, but alpha 6 and beta 1 integrins were observed by confocal microscopy to be expressed over the entire cell surface, while alpha 2, alpha 5 and alpha v beta 3 integrins localized along dendritic processes or at their tips. In accordance with the implications of these distribution patterns, anti-beta 1 and anti-alpha 6 integrin monoclonal antibodies blocked melanocyte attachment to laminin, while anti-alpha 2, anti-alpha 5 and anti-alpha v beta 3 inhibited dendrite outgrowth but did not block substratum attachment on either laminin or type IV collagen. On the basis of these data and the known characteristics of integrin molecules, we conclude that melanocyte attachment to laminin is mediated primarily by alpha 6 beta 1 integrin in a Ca(2+)-independent, Mg(2+)- and/or Mn(2+)-dependent manner, while dendrite outgrowth on laminin and type IV collagen requires extracellular Ca2+ and is mediated by alpha v beta 3 as well as alpha 2 and alpha 5 integrins.

Cellular phenotypes of normal and leukemic hemopoietic cells determined by analysis with selected antibody combinations

Blood ◽  
1980 ◽  
Vol 56 (3) ◽  
pp. 430-441 ◽  
Author(s):  
G Janossy ◽  
FJ Bollum ◽  
KF Bradstock ◽  
J Ashley
Keyword(s):  
Bone Marrow ◽  
Monoclonal Antibodies ◽  
Single Cell ◽  
Normal Cell ◽  
Cell Types ◽  
Precursor Cells ◽  
Leukemic Cells ◽  
Double Staining ◽  
Cell Assays ◽  
Cellular Phenotypes

Abstract Individual leukemic cells and the corresponding rare normal cell types in nonleukemic bone marrow were analyzed with various combinations of antisera (labeled with different fluorochromes: TRITC and FITC). Double staining for membrane Ia-like molecules (TRITC) and nuclear terminal transferase (FITC) was a very useful combination that distinguished common non-T, non-B ALL (Ia+,TdT+) and thymic ALL (Ia-,TdT+) from the rare cases of B ALL (Ia+,TdT-) and from AML (frequently Ia+, TdT-; in some cases Ia-, TdT-). Additional antisera (such as anti-ALL, anti- HuTLA, anti-immunoglobulin reagents, etc.) confirmed the diagnosis and further characterized the leukemic blasts. Ia+,TdT+ cells could be observed in low numbers in normal and nonleukemic regenerating marrow and were probably normal precursor cells; this reagent combinations was, therefore, not useful for monitoring residual non-T, non-B ALL blasts in treated patients. Other marker combinations detecting pre-B ALL blasts (double staining for cytoplasmic IgM and nuclear TdT) and Thy-ALL blasts (HuTLA+,TdT+) were, however, virtually leukemia specific in the bone marrow and could be used to effectively monitor residual leukemic cells throughout the disease. These combined single-cell assays are not only economical and informative but are also important for assessing the heterogeneity of leukemia and for standardizing new mouse or rat monoclonal antibodies for diagnosis.

Antagonist, Partial Agonist, and Full Agonist Imidazo[1,5-a]quinoxaline Amides and Carbamates Acting through the GABAA/Benzodiazepine Receptor

1994 ◽  
Vol 37 (6) ◽  
pp. 758-768 ◽  
Author(s):  
Ruth E. TenBrink ◽  
Wha B. Im ◽  
Vimala H. Sethy ◽  
Andrew H. Tang ◽  
Don B. Carter
Keyword(s):  
Partial Agonist ◽  
Benzodiazepine Receptor ◽  
Full Agonist

scholarly journals Identification of new gonadotrophin-releasing hormone partial agonists

2006 ◽  
Vol 189 (3) ◽  
pp. 509-517 ◽  
Author(s):  
Alfredo Leaños-Miranda ◽  
Alfredo Ulloa-Aguirre ◽  
Laura A Cervini ◽  
Jo Ann Janovick ◽  
Jean Rivier ◽  
...  
Keyword(s):  
Inositol Phosphate ◽  
Partial Agonist ◽  
Prolonged Treatment ◽  
Complete Suppression ◽  
Antagonist Activity ◽  
Gnrh Analogues ◽  
Full Agonist ◽  
Partial Agonists ◽  
Stimulation Of

GnRH agonists or antagonists are currently utilized as therapeutic agents in a number of diseases. A side-effect of prolonged treatment with GnRH analogues is hypoestrogenism. In this study, we tested the in vitro potency of different GnRH analogues originally found to be partial agonists (i.e. analogues with decreased efficacy for activating or stimulating their cognate receptor) as well as novel analogues, to identify compounds that might potentially be useful for partial blockade of gonadotrophin release. Cultured COS-7 cells transiently expressing the rat or human GnRH receptor (GnRHR) were exposed to increasing concentrations (10−8 to 10−5 M) of GnRH analogues (c(4–10)[Asp4,DNal6,Dpr10]-GnRH; c(4–10) [Dpr4,DNal6,Asp10]-GnRH; c(4–10)[Cys4,10,DNal6]-GnRH; c[Eaca1,DNal6]-GnRH; c[Gly1,DNal6]-GnRH; c[βAla1,DTrp6]-GnRH; c[Dava1,DNal6]-GnRH; c[Gaba1, DNal6]-GnRH), and the ability of these analogues to provoke or antagonize GnRH-stimulated inositol phosphate production was assessed. With both human and rat GnRHRs, c[Eaca1,DNal6]-GnRH, c[Gly1,DNal6]-GnRH, c[βAla1,DTrp6]-GnRH and c[Dava1,DNal6]-GnRH exhibited partial agonist activity (35–87% of the maximal efficacy shown by 10−6 M GnRH), whereas c[Gaba1,DNal6]-GnRH behaved as a partial agonist with the human GnRHR and as full agonist with the rat GnRHR. c(4–10)[Asp4, DNal6,Dpr10]-GnRH and c(4–10)[Dpr4,DNal6,Asp10]-GnRH exhibited full antagonist activity with both GnRHRs, and c(4–10) [Cys4,10,DNal6]-GnRH was a weak, partial agonist with the human GnRHR and a full antagonist with the rat GnRHR. With the exception of c[Gaba1,DNal6]-GnRH stimulation of the human GnRHR, and c[Dava1,DNal6]-GnRH and c[Gaba1, DNal6]-GnRH stimulation of the rat GnRHR, all partial agonists also exhibited antagonist activity in the presence of the exogenous full agonist. The results demonstrate that structurally similar analogues display variable potencies and efficacies in vitro for a specific GnRHR as well as for the human versus the rat GnRHR. Their ultimate in vivo usefulness to treat clinical conditions in which complete suppression of gonadotroph activity is not required remains to be investigated.

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