Purpose: To assess the effect of prostaglandin (PG) F2alpha and PGE1 on flow through the trabecular meshwork in organ preserved human anterior segments.
Methods: Isolated human anterior segments were perfused under standard conditions at a constant pressure of 10 mm Hg, while flow was continuously monitored. After a stabilization period, 6 consecutive concentrations of PGs were administered. cAMP levels were determined in the perfusate at baseline conditions and at 10(-6) M PG.
Results: Perfusion with concentrations ranging from 10(-10) to 10(-5) M PGE1 resulted in a dose-dependent increase in flow (P < 0.0001), reaching a plateau of a 26% increase at 10(-7) M. Perfusion with PGF2alpha or placebo (Eagle's minimum essential medium) did not influence baseline flow. cAMP produced by human anterior segments increased from 4.8+/-0.6 pmol x 30 min(-1) per anterior segment at baseline to 19.2+/-4.8 pmol x 30 min(-1) per anterior segment after perfusion with 10(-6) M PGE1 (P < 0.005). Perfusion with 10(-6) M PGF2alpha did not influence baseline cAMP production. Perfusion with 10(-5) M GDP-beta-S, an inhibitor of G protein, before and in combination with 10(-6) M PGE1 completely inhibited the increase in flow and cAMP production as observed after PGE1 alone. Perfusion with 10(-5) M GDP-beta-S alone did not affect baseline cAMP production.
Conclusions: In organ preserved perfused human anterior segments, flow and cAMP production in the perfusate are not mediated by receptor-coupled adenylyl cyclase activity at baseline conditions. Perfusion with PGE1 is suggested to increase flow through the trabecular meshwork by stimulation of prostanoid EP2 receptor subtype, EP4 receptor subtype, or both, coupled to G(s) protein, inducing activation of the adenylyl cyclase catalytic unit. The results may indicate a physiological role for EP2 receptor subtype, EP4 receptor subtype, or both in the modulation of flow through the trabecular meshwork after stimulation.
Download full-text PDF |
Source |
|---|
Publication Analysis
Top Keywords
Similar Publications
The appearance of external genital organs and anogenital distance in male fetal cadavers.
Anat Sci Int
January 2025
Department of Anatomy, Faculty of Medicine, Üsküdar University, Istanbul, Türkiye.
This study aimed to determine the normal size of the male external genital organs and anogenital distance in human fetuses during the fetal period through the anatomic morphometric method. The study was performed on 104 spontaneously aborted human male fetuses aged between 10 and 39 weeks of gestation. Fetuses were divided into groups according to gestational weeks, months, and trimesters.
View Article and Find Full Text PDFComparison between ruptured anterior choroidal artery aneurysms and ruptured intracranial aneurysms in other locations in relation to aneurysm dimensions at rupture.
Acta Neurochir (Wien)
January 2025
Division of Neuroradiology and Joint Department of Medical Imaging, University Health Network and Toronto Western Hospital, Toronto, ON, M5T 2S8, Canada.
Purpose: It was noticed that anterior choroidal artery (AChoA) aneurysms appear to rupture at relatively smaller sizes compared with aneurysms in other intracranial locations, based on anecdotal clinical experience. We therefore aimed to compare ruptured AChoA aneurysms with other ruptured aneurysms in other intracranial locations, pertaining to aneurysm dimensions. This may help in finding out if the rupture risk stratification, based on the amalgamation of aneurysms of multiple locations in one group, precisely estimates aneurysm rupture risk.
View Article and Find Full Text PDFCoregistration of eye movements and EEG reveals frequency effects of words and their constituent characters in natural silent Chinese reading.
Sci Rep
January 2025
Department of Psychology and Behavioral Sciences, Zhejiang University, Hangzhou, 310058, China.
We conducted two experiments to examine the lexical and sub-lexical processing of Chinese two-character words in reading. We used a co-registration electroencephalogram (EEG) for the first fixation on target words. In Experiment 1, whole-word occurrence frequency and initial constituent character frequency were orthogonally manipulated, while in Experiment 2, whole-word occurrence frequency and end constituent character frequency were orthogonally manipulated.
View Article and Find Full Text PDF[Bioinformatics and animal experiments reveal mechanism of Linggui Zhugan Decoction in ameliorating chronic heart failure after myocardial infarction via HIF-1α/HO-1 signaling pathway].
Zhongguo Zhong Yao Za Zhi
December 2024
School of Integrated Chinese Medicine and Western Medicine, Anhui University of Chinese Medicine Hefei 230012, China Anhui Province Key Laboratory of Chinese Medicinal Formula Hefei 230012, China.
This study aims to investigate the effect of Linggui Zhugan Decoction(LGZGD) on autophagy in the mouse model of chronic heart failure(CHF) induced by myocardial infarction(MI), as well as the regulatory effect of LGZGD on the hypoxia-inducible factor-1α(HIF-1α)/heme oxygenase-1(HO-1) signaling pathway, based on bioinformatics and animal experiments. The active ingredients and corresponding targets of LGZGD were retrieved from the Traditional Chinese Medicine Systems Pharmacology and Analysis Database, and GEO, GeneCards, and DisGeNET were searched for the disease targets. Cytoscape was used to establish a "drug-component-target" network.
View Article and Find Full Text PDFAltered Neural Responses to Punishment Learning in Conduct Disorder.
Biol Psychiatry Cogn Neurosci Neuroimaging
January 2025
Department of Child and Adolescent Psychiatry, Faculty of Medicine, TUD Dresden University of Technology, German Center for Child and Adolescent Health (DZKJ), partner site Leipzig/Dresden, Dresden, Germany.
Objective: Conduct disorder (CD) is associated with deficits in the use of punishment for reinforcement learning (RL) and subsequent decision-making, contributing to reckless, antisocial, and aggressive behaviors. Here, we used functional magnetic resonance imaging (fMRI) to examine whether differences in behavioral learning rates derived from computational modeling, particularly for punishment, are reflected in aberrant neural responses in youths with CD compared to typically-developing controls (TDCs).
Methods: 75 youths with CD and 99 TDCs (9-18 years, 47% girls) performed a probabilistic RL task with punishment, reward, and neutral contingencies.
Want AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!