The review provides a survey of current knowledge about the changes in hormone-sensitive adenylate cyclase complex of erythroid cells. The basal enzyme activity decreases continuously during differentiation and maturation. Guanine nucleotides (GTP and GMP-P (NH)P) increase the adenylate cyclase activity of both early and late rabbit bone marrow erythroblasts. The stimulating effect of the beta 2-adrenergic drugs such as L-isoprenaline is limited to the immature cells. L-noradrenaline, a beta 1-agonist is inactive. The lack of response of non-dividing rabbit erythroblasts to beta-adrenergic stimuli is not due to loss of beta-receptors during differentiation, but to a decrease in the effectiveness of the coupling between the components of the system: receptor-guanine nucleotide regulatory protein-catalytic subunit. Prostaglandins E1 and E2 consistently enhance adenylate cyclase activity of erythroblasts on different stages of development. Erythropoietin (0.2 U/ml) causes a transient increase in the activity of adenylate cyclase, which is maximal by 20 min incubation of the cells in the presence of the hormone and disappears within 4 hours. The magnitude of the response to erythropoietin depends on the stage of erythroid cell development and is inverse related to the extent of previous hormonal stimulation of the cell.
Download full-text PDF |
Source |
---|
Histol Histopathol
January 2025
Institute of Anorectal Diseases, School of Integrated Traditional Chinese and Western Medicine Clinical Medicine, North Sichuan Medical College, Nanchong, Sichuan, PR China.
Slow transit constipation (STC) is a colonic motor disorder characterized by a marked delay in the movement of substances through the colon. Traditional Chinese medicine (TCM) is a treasure trove of natural compounds, which is effective in treating constipation with relatively minor side effects. Zengye decoction (ZYD), a classic herbal formula in TCM, is used for moistening the intestines and relieving constipation.
View Article and Find Full Text PDFInt J Mol Sci
January 2025
Sechenov Institute of Evolutionary Physiology and Biochemistry, Russian Academy of Sciences, St. Petersburg 194223, Russia.
The approaches to correct thyroid deficiency include replacement therapy with thyroid hormones (THs), but such therapy causes a number of side effects. A possible alternative is thyroid-stimulating hormone (TSH) receptor activators, including allosteric agonists. The aim of this work was to study the effect of ethyl-2-(4-(4-(5-amino-6-(-butylcarbamoyl)-2-(methylthio)thieno[2,3-d]pyrimidin-4-yl)phenyl)--1,2,3-triazol-1-yl) acetate (TPY3m), a TSH receptor allosteric agonist developed by us, on basal and thyroliberin (TRH)-stimulated TH levels and the hypothalamic-pituitary-thyroid (HPT) axis in male rats with high-fat diet/low-dose streptozotocin-induced type 2 diabetes mellitus (T2DM).
View Article and Find Full Text PDFEur J Neurosci
January 2025
Faculty of Medicine, Collegium Medicum, Mazovian Academy in Plock, Plock, Poland.
Chronic migraine (CM) is the ultimate and most burdensome form of the transformation from episodic migraine (EM), called chronification. The mechanism behind migraine chronification is poorly known and difficult to explore as CM has the same spectrum of pathogenesis as EM and the EM-CM transition is bidirectional. Central sensitization (CS) is a key phenomenon in migraine: its mechanisms include disturbed neural plasticity, which is the ability of the nervous system to adapt to endo- and exogenous changes.
View Article and Find Full Text PDFACS Chem Biol
January 2025
Department of Chemistry, Stony Brook University, Stony Brook, New York 11794-3400, United States.
OaPAC, the photoactivated adenylyl cyclase from , is composed of a blue light using FAD (BLUF) domain fused to an adenylate cyclase (AC) domain. Since both the BLUF and AC domains are part of the same protein, OaPAC is a model for understanding how the ultrafast modulation of the chromophore binding pocket caused by photoexcitation results in the activation of the output domain on the μs-s time scale. In the present work, we use unnatural amino acid mutagenesis to identify specific sites in the protein that are involved in transducing the signal from the FAD binding site to the ATP binding site.
View Article and Find Full Text PDFFunction (Oxf)
January 2025
Institute for Integrative Physiology, Department of Medicine, Pritzker School of Medicine, University of Chicago, Chicago, IL. 60637, USA.
Patients with obstructive sleep apnea (OSA) experience chronic intermittent hypoxia (CIH). OSA patients and CIH-treated rodents exhibit overactive sympathetic nervous system and hypertension, mediated through hyperactive carotid body (CB) chemoreflex. Activation of olfactory receptor 78 (Olfr78) by hydrogen sulfide (H2S) is implicated in CB activation and sympathetic nerve responses to CIH, but the downstream signaling pathways remain unknown.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!