Prolactin Binding Sites in Normal Uterus and the Uterus with Adenomyosis in Mice

In: ZOOLOGICAL SCIENCE · 1993 · vol. 10(2) , pp. 353–360 · doi:10.1007/bf00049532 · W24407925
article OA: green CC0 ⤵ 4 in-corpus citations
AI-generated summary by claude@2026-06, 2026-06-11

This study examined the pH dependence of fluorescence quenching in spinach thylakoids, identifying two distinct quenching mechanisms, one similar to high-energy-state quenching (qE) and the other not.

One-sentence paraphrase of the abstract; not a substitute for reading it. No clinical advice. How this works

AI-generated deep summary by claude@2026-06, 2026-06-11 · read from full text

The paper examined pH-dependent chlorophyll fluorescence quenching in spinach thylakoids by adding nigericin to dissipate the transthylakoid pH gradient, with DCMU to prevent photochemical quenching. Thylakoids from dark-adapted versus preilluminated leaves were compared, revealing an ascorbate-dependent, antimycin A–sensitive quenching whose pH dependence differed between conditions, with preillumination increasing quenching at pH values where dark thylakoids showed little quenching. A second ferricyanide-driven quenching component was identified that could be reversed by ascorbate and showed the same pH dependence in both thylakoid types; the main limitation is that the study is mechanistic and confined to photosynthetic membranes from spinach rather than any direct biological disease context. The paper does not explicitly discuss endometriosis or adenomyosis; it was included in the corpus via a keyword match in the upstream search index.

Read from the paper's body, not the abstract. Not a substitute for reading the paper. No clinical advice. How this works

Abstract

The pH dependence of maximum chlorophyll fluorescence yield (Fm) was examined in spinach thylakoids in the presence of nigericin to dissipate the transthylakoid pH gradient. 3-(3',4'-dichlorophenyl)-1,1-dimethylurea (DCMU) was present to eliminate photochemical quenching. Thylakoids were prepared from dark adapted leaves ('dark' thylakoids) or preilluminated leaves ('light' thylakoids). In the latter there had been approximately 50% conversion of the xanthophyll violaxanthin to zeaxanthin, while no conversion had occurred in the former. In the presence of a reductant such as ascorbate, antimycin A sensitive quenching was observed (half maximal quenching at 5 μM), whose pH dependence differed between the two types of thylakoid. Preillumination of leaves resulted in more quenching at pH values where very little quenching was observed in 'dark' thylakoids (pH 5-7.6). This was similar to activation of high-energy-state quenching (qE) observed previously (Rees D, Young A, Noctor G, Britton G and Horton P (1989) FEBS Lett 256: 85-90). Thylakoids isolated from preilluminated DTT treated leaves, that contained no zeaxanthin, behaved like dark thylakoids. A second form of quenching was observed in the presence of ferricyanide, that could be reversed by the addition of ascorbate. This was not antimycin A sensitive and showed the same pH dependence in both types of thylakoid. The former type of quenching, but not the latter, showed similar low temperature fluorescence emission spectra to qE, and was considered to occur by the same mechanism.
Full text 8,888 characters · extracted from oa-doi-fallback · 2 sections · click to expand

Abstract

The pH dependence of maximum chlorophyll fluorescence yield (Fm) was examined in spinach thylakoids in the presence of nigericin to dissipate the transthylakoid pH gradient. 3-(3′,4′-dichlorophenyl)-1,1-dimethylurea (DCMU) was present to eliminate photochemical quenching. Thylakoids were prepared from dark adapted leaves (‘dark’ thylakoids) or preilluminated leaves (‘light’ thylakoids). In the latter there had been approximately 50% conversion of the xanthophyll violaxanthin to zeaxanthin, while no conversion had occurred in the former. In the presence of a reductant such as ascorbate, antimycin A sensitive quenching was observed (half maximal quenching at 5 μM), whose pH dependence differed between the two types of thylakoid. Preillumination of leaves resulted in more quenching at pH values where very little quenching was observed in ‘dark’ thylakoids (pH 5–7.6). This was similar to activation of high-energy-state quenching (qE) observed previously (Rees D, Young A, Noctor G, Britton G and Horton P (1989) FEBS Lett 256: 85–90). Thylakoids isolated from preilluminated DTT treated leaves, that contained no zeaxanthin, behaved like dark thylakoids. A second form of quenching was observed in the presence of ferricyanide, that could be reversed by the addition of ascorbate. This was not antimycin A sensitive and showed the same pH dependence in both types of thylakoid. The former type of quenching, but not the latter, showed similar low temperature fluorescence emission spectra to qE, and was considered to occur by the same mechanism. Similar content being viewed by others Abbreviations - DCMU: - 3(3′,4′-dichlorophenyl)-1,1-dimethylurea - DTT: - dithiothreitol - EDTA: - Ethylenediaminetetra-acetic acid - F0 : - dark level fluorescence yield - Fm : - maximum fluorescence yield - Fv/Fm : - ratio of variable to total fluorescence yield - Hepes: - 4-(2-hydroxyethyl)1-piperazineethanesul-phonic acid - Mes: - 2-(N-morpholino) ethanesulfonate - pH: - transthylakoid pH gradient - PS I: - Photosystem I - PS II: - Photosystem II - QA : - primary stable electron acceptor of Photosystem II - qE: - high-energy-state fluorescence quenching

References

AdamsIII WW, Demmig-Adams B and Winter K (1990) Relative contributions of zeaxanthin-related and zeaxanthin-unrelated types of ‘high-energy-state’ quenching of chlorophyll fluorescence in spinach leaves exposed to various environmental conditions. Plant Physiol 92: 302–309 Barry P, Young AJ and Britton G (1990) Photodestruction of pigments in higher plants by herbicide action. I. The effect of DCMU (diuron) on isolated chloroplasts. J Exp Bot 41: 123–129 Bilger W, Björkman O and Thayer SS (1989) Light-induced spectral absorbance changes in relation to photosynthesis and the epoxidation state of xanthophyll cycle components in cotton leaves. Plant Physiol 91: 542–551 Briantais JM, Vernotte C, Picaud M and Krause GH (1979) A quantitative study of the slow decline of chlorophyll-a fluorescence in isolated chloroplasts. Biochim Biophys Acta 548: 128–138 Crofts J and Horton P (1991) Dissipation of excitation energy by Photosystem 2 particles at low pH. Biochim Biophys Acta 1058: 187–193 Demmig B, Winter K, Kruger A and Czygan F-C (1987) Photoinhibition and zeaxanthin formation in intact leaves. A possible role of the xanthophyll cycle in the dissipation of excess light. Plant Physiol 84: 218–224 Demmig B, Winter K, Kruger A and Czygan F-C (1988) Zeaxanthin and the heat dissipation of excess light energy in Nerium oleander exposed to a combination of high light and water stress. Plant Physiol 87: 17–24 Demmig-Adams B (1990) Carotenoids and photoprotection in plants: A role for the xanthophyll zeaxanthin. Biochim Biophys Acta 1020: 1–24 Demmig-Adams B and AdamsIII WW (1990) The carotenoid zeaxanthin and ‘high-energy-state quenching’ of chlorophyll fluorescence. Photosynth Res 25: 187–198 Demmig-Adams B, Adams WW, Heber U, Neimanis S, Winter K, Kruger A, Czygan FC, Bilger W and Björkman O (1990) Inhibition of zeaxanthin formation and of rapid changes in radiationless energy dissipation by dithiothreitol in spinach leaves and chloroplasts. Plant Physiol 92: 293–301 Demmig-Adams B, Winter K, Kruger A and Czygan FC (1989) Zeaxanthin and the induction and relaxation kinetics of the dissipation of excess excitation energy in leaves in 2% O2, 0% CO2. Plant Physiol 90: 887–893 Genty B, Briantais J-M and Baker NR (1989) The relationship between quantum yield of photosynthetic electron transport and quenching of chlorophyll fluorescence. Biochim Biophys Acta 990: 87–92 Horton P and Hague A (1988) Studies on the induction of chlorophyll fluorescence in isolated barley protoplasts. IV. Resolution of non-photochemical quenching. Biochim Biophys Acta 932: 107–115 Horton P, Noctor G and Rees D (1990) Regulation of light harvesting and electron transport in Photosystem II. In: Zelitch I (ed) Perspectives in Biochemical and Genetic Regulation of Photosynthesis, pp 145–158. Alan Liss Inc., New York Horton P, Ruban AV, Rees D, Pascall AA, Noctor G and Young AJ (1991) Control of the light-harvesting function of chloroplast membranes by aggregation of the LHC II chlorophyll-protein complex. FEBS Lett 292: 1–4 Krause GH and Behrend U (1983) Characterization of chlorophyll fluorescence quenching in chloroplasts by fluorescence spectroscopy at 77 K. II. ATP-dependent quenching. Biochim Biophys Acta 723: 176–181 Krause GH and Laasch H (1987) Energy-dependent chlorophyll fluorescence quenching in chloroplasts correlated with quantum yield of photosynthesis. Z Naturforsch 42: 581–584 Krause GH, Laasch H and Weis E (1988) Regulation of thermal dissipation of absorbed light energy in chloroplasts indicated by energy dependent fluorescence quenching. Plant Physiol Biochem 26: 445–452 Krause GH, Vernotte C and Briantais J-M (1982) Photoinduced quenching of chlorophyll fluorescence in intact chloroplasts and algae. Resolution into two components. Biochim Biophys Acta 679: 116–124 Mills J and Barber J (1975) Energy-dependent cation-induced control of chlorophyll a fluorescence in isolated intact chloroplasts. Archives Biochem Biophys 170: 306–314 Neubauer C and Schreiber U (1987) The polyphasic rise of chlorophyll fluorescence upon upset of strong continuous illumination. I. Saturation characteristics and partial control by the Photosystem II acceptor side. Z Naturforsch 42c: 1246–1254 Noctor G, Rees D, Young A and Horton P (1991) The relationship between zeaxanthin, energy-dependent quenching of chlorophyll fluorescence, and trans-thylakoid pH gradient in isolated chloroplasts. Biochim Biophys Acta 1057: 320–330 Oxborough K and Horton P (1988) A study of the regulation and function of energy-dependent quenching in pea chloroplasts. Biochim Biophys Acta 934: 135–143 Quick WP and Horton P (1984) Studies on the induction of chlorophyll fluorescence in barley protoplasts. II. Resolution of fluorescence quenching by redox state and the transthylakoid pH gradient. Proc R Soc Lond B 220: 371–382 Rees D, Noctor GD and Horton P (1990) The effect of high-energy-state excitation quenching on maximum and dark level chlorophyll fluorescence yield. Photosynth Res 25: 199–212 Rees D, Young A, Noctor G, Britton G and Horton P (1989) Enhancement of the pH-dependent dissipation of excitation energy in spinach chloroplasts by light-activation: Correlation with the synthesis of zeaxanthin. FEBS Lett 256: 85–90 Rijgersberg CP, Amesz J, Thielen APGM and Swager JA (1979) Fluorescence emission spectra of chloroplasts and subchloroplast preparations at low temperature. Biochim Biophys Acta 545: 473–482 Ruban AV, Rees D, Noctor GD, Young A and Horton P (1991) Long wavelength chlorophyll species are associated with amplification of high-energy-state excitation quenching in higher plants. Biochim Biophys Acta 1059: 355–360 Schreiber U and Neubauer C (1989) Correlation between dissipative fluorescence quenching at Photosystem II and 50 μs recombination luminescence. FEBS Lett 258: 339–342 Vernotte C, Etienne AL and Briantais J-M (1979) Quenching of the system 2 chlorophyll fluorescence by the plastoquinone pool. Biochim Biophys Acta 545: 519–527 Weis E and Berry JA (1987) Quantum efficiency of PS 2 in relation to ‘energy’ dependent quenching of chlorophyll fluorescence. Biochim Biophys Acta 894: 198–208 Wraight CA, Kraan GPB and Gerrits NM (1972) The pH dependence of delayed and prompt fluorescence in uncoupled chloroplasts. Biochim Biophys Acta 283: 259–267 Author information Authors and Affiliations Rights and permissions About this article Cite this article Rees, D., Noctor, G., Ruban, A.V. et al. pH dependent chlorophyll fluorescence quenching in spinach thylakoids from light treated or dark adapted leaves. Photosynth Res 31, 11–19 (1992). https://doi.org/10.1007/BF00049532 Received: Accepted: Issue date: DOI: https://doi.org/10.1007/BF00049532

Text is read by the "Ask this paper" AI Q&A widget below. Extraction quality varies by source — PMC NXML preserves structure cleanly, OA-HTML may include some navigation residue, and OA-PDF can have broken hyphenation. The publisher copy (via DOI) is the canonical version.

My notes (saved in your browser only)

Ask this paper AI returns verbatim quotes from the full text · source: oa-doi-fallback

Answers must be backed by verbatim quotes from this paper's full text. Hallucinated quotes are dropped automatically; if no verbatim passage answers the question, we say so. How this works

Condition tags

adenomyosis

Citation neighborhood (sparse)

Too few in-corpus citations on either side for a chart; here are the lists.

Cited by (4)

Cited by (4)

Source provenance

openalex
last seen: 2026-06-10T17:14:06.276822+00:00
License: CC0 · commercial use OK