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BackgroundA close association exists between renal impairment (RI) and atrial fibrillation (AF) occurrence. Increased activity of the sympathetic nervous system (SNS) may contribute to the development of AF associated with RI. Renal denervation (RDN) decreases central sympathetic activity.ObjectiveThe main objective of the study was to explore the effects of RDN on AF occurrence and its possible mechanisms in beagles with RI.MethodsUnilateral RI was induced in beagles by embolization of small branches of the renal artery in the right kidney using gelatin sponge granules in Model (n = 6) and RDN group (n = 6). The Sham group (n = 6) underwent the same procedure, except for embolization. Then animals in RDN group underwent radiofrequency ablation of the renal sympathetic nerve. Cardiac electrophysiological parameters, blood pressure, left ventricular end-diastolic pressure, and AF inducibility were investigated. The activity of the SNS, renin-angiotensin-aldosterone system (RAAS), inflammation and atrial interstitial fibrosis were measured.ResultsEmbolization of small branches of the renal artery in the right kidney led to ischemic RI. Heart rate, P wave duration and BP were increased by RI, which were prevented or attenuated by RDN. Atrial effective refractory period was shortened and AF inducibility was increased by RI, which were prevented by RDN. Antegrade Wenckebach point was shortened, atrial and ventricular rates during AF were increased by RI, which were attenuated or prevented by RDN. Levels of norepinephrine, renin and aldosterone in plasma, norepinephrine, angiotensin II, aldosterone, interleukin-6 and high sensitivity C-reactive protein in atrial tissue were elevated, and atrial interstitial fibrosis was enhanced by RI, which were attenuated by RDN.ConclusionsRDN significantly reduced AF inducibility, prevented the atrial electrophysiological changes in a model of RI by combined reduction of sympathetic drive and RAAS activity, and inhibition of inflammation activity and fibrotic pathway in atrial tissue.

Pan-African basement rocks and the Palaeozoic cover series of the Menderes Massif are exposed around Derbent (Alaşehir) in the eastern part of the Ödemiş-Kiraz submassif. Garnet-mica schists of the Pan-African basement are intruded by the protoliths of orthogneisses and Triassic leucocratic orthogneisses. This study focuses on the geochronology and geochemistry of orthogneisses related to the Pan-African evolution of the Menderes Massif in latest Proterozoic time. Geochemical data suggest that the orthogneisses were derived from S-type, peraluminous, syn- to post-collisional granitoids of calc-alkaline affinity. Zircon grains from the orthogneisses, which are euhedral with typical igneous morphologies, were dated by the Pb-Pb evaporation method. Single zircon ages of two samples yielded 207Pb/206Pb ages of 561.5±1.8 Ma and 570.5±2.2 Ma. These ages are interpreted as the time of protolith emplacement of the orthogneisses. This major magmatic episode of the Menderes Massif can be attributed the Pan-African Orogeny which was related to the closure of the ocean basins and amalgamation of East and West Gondwana., Menderes Masifi’nin Pan-Afrikan yafll› temel kayalar› ve Paleozoyik örtü serileri Ödemifl-Kiraz asmasifi’nin do¤usunda yer alan Derbent (Alaflehir) çevresinde yüzlek vermektedir. Pan-Afrikan temele ait granat-mika flistler, ortognayslar ve Triyas yafll› lökokratik ortognayslar›n ilksel kayalar› taraf›ndan intrüze olmufllard›r. Bu çal›flma, Proterozoyik sonunda Menderes Masifi’nin Pan-Afrikan evrimiyle iliflkili olan ortognayslar›n jeokimyas› ve jeokronolojisi üzerinedir. Jeokimyasal veriler ortognayslar›n S-tipli, peralumino ve kalkalkalen karakterli, sin-/posttektonik granitoyidlerden türedi¤ini göstermektedir. Ortognayslardan ayr›lan tipik magmatik ve öz flekilli zirkonlardan Pb-Pb evaporasyon yöntemiyle yafl tayinleri yap›lm›flt›r. ‹ki örne¤in tek zirkon 207Pb/206Pb yafllar› ortalama 561.5±1.8 my ve 570.5±2.2 my olarak elde edilmifltir. Bu yafllar ortognayslar›n ilksel kayalar›n›n sokulum yafl› olarak yorumlanm›flt›r. Menderes Masifi’ndeki bu ana magmatik olay okyanus havzalar›n›n kapanmas› ve Do¤u ve Bat› Gondvana’n›n çarp›flmas›na ba¤lant›l› Pan-Afrikan orojeneziyle iliflkilendirilebilir.

ÖZMenderes Masifi’nin güneyinde yeralan Çine Asmasifi’nin (Seykel bölgesi) Pan-Afrikan temel kayaları baskınolarak biyotit- ve lökokratik turmalin ortognayslardan oluşmaktadır. ÇineAsmasifi’nin güney sınırı boyunca lökokratik ortognayslar, biyotit ortognayslarınyanı sıra her ikisinin de çevre kayasını oluşturan granat mika şistler içerisinesokulum yapmışlardır. Sayısız büyük plüton, stok ve damardan oluşan bu kayalariyi korunmuş intrüzif dokanaklar sunmaktadır.Granat mika şistlerin ilkselkayalarının zirkon yaş verilerine dayalı çökelme yaşları 550 - 600 my (geçNeoproterozoyik) arasına sıkışmaktadır. Zirkon yaşları bu metakırıntılılarınolasılı kaynak bölgesi olarak Mozambik Kuşağı içerinde kalan Arap-Nübye Kalkanıve Kuzey Afrika’yı işaret etmektedir. Biyotit ortognaysların ilksel granitlerininzirkon Pb-Pb evaporasyon sokulum yaşları 552.1 ± 2.4 myolarak saptanmıştır. Benzer şekilde lökokratik turmalin ortognaysların ilkselkayalarının sokulum yaşları da zirkon Pb-Pb evaporasyon ve U-Pb LA-ICP-MSyöntemleriyle sırasıyla 545.6 ± 2.7 my ve 552.4± 6.8 my olarak bulunmuştur. Bu granitoyidler Mozambik Okyanusu boyunca Doğu veBatı Gondawana’nın çarpışma sürecininson evresinde kıtasal kabuğun kalınlaşması sonucu gelişen Pan-Afrikan yaşlı yaygınasidik magmatik aktivitenin ayrımlaşmış ürünleridir. Paleozoyik yaşlı örtüserilerine ait muskovit kuvars şistler içerisinde bulunan 550 my yaşlı taşınmışzirkonlar, temelde yer alan Pan-Afrikan yaşlı granitoyidlerin bu sedimanterkayalar için kaynak oluşturduğunu göstermektedir.ABSRACTOrthogneisses,biotite- and leucocratic tourmaline orthogneisses are the dominant rock types ofthe Pan-African basement in the Çine submassif, Seykel area, of the MenderesMassif. Along the southern flank of the Çine submassif, we recognizedwell-preserved primary contact relationship between biotite- and leucocratictourmaline orthogneisses and country rocks as the orthogneisses representnumerous large plutons, stocks and vein rocks intruded into a basement ofgarnet mica schists.Based on the radiometricdata, the primary deposition age of the precursors of the country rocks, garnetmica schist, can be constrained between 600 Ma and 550 Ma (latestNeoproterozoic). The North Africa -Arabian-Nubian Shield in the Mozambique Belt can be suggested as the possibleprovenance of these metaclastics. Zircon Pb-Pb evaporation geochronology yielded 552.1 ± 2.4 Ma ages interpretedas the crystallisation ages of the granitic precursors of the biotiteorthogneisses. Similarly the intrusion ages of the protolithes of the leucocratictourmaline orthogneisses were dated at 545.6 ± 2.7 Ma and552.4 ± 6.8 Ma byzircon evaporation and U-Pb LA-ICP-MS methods, respectively. Thesegranitoids represent the differentiated products of the samewidespread Pan-African acidic magmatic activity, which can be attributed to thethickening of the continental crust during the final collision of East and WestGondwana along the Mozambique Ocean. Detritalzircon ages at about 550 Ma in the Palaeozoic muscovitequartz schists show that these Pan-African granitoids in the basement form thesource rocks of the cover series of the Menderes Massif.

The Karaburun Peninsula, which is considered part of the Anatolide-Tauride Block of Turkey, contains clastic and carbonate sequences deposited on the northern margin of Gondwana. The Palaeozoic clastic sequence, which is intruded by the Early Triassic granitoid and tectonically overlies a Mesozoic melange sequence, can be divided into three subunits: a lower clastic subunit consisting of a sandstone-shale alternation, an upper clastic subunit consisting of black chert-bearing shales, sandstone and conglomerate, and a Permo-Carboniferous carbonate subunit. The lower Triassic Karaburun I-type granitoid has a high initial Sr-87/Sr-86 ratio (0.709021-0.709168), and low Nd-143/Nd-144 ratio (0.512004-0.512023) and epsilon Nd (-5.34 to -5.70) isotopic values. Geochronological data indicate a crystallization (intrusion) age of 247.1 +/- 2.0 Ma (Scythian). Geochemically, the acidic magmatism reflects a subduction-related continental-arc basin tectonic setting, which can be linked to the opening of the northern branch of Neo-Tethys as a continental back-arc rifting basin on the northern margin of Gondwana. This can be related to the closure through southward subduction of the Palaeotethys Ocean beneath Gondwana.

The Menderes Massif is a metamorphic complex cropping out on a large region in the Alpineorogenic belt in Western Anatolia. The massif mainly, is made up of a Precambrian basement and the overlyingPalaeozoic-Early Tertiary cover series. The basement comprises Late Proterozoic metaclastics composed ofparagneiss and high grade micaschists, syn to post-tectonical Pan-African orthogneisses that have intruded intothem, and metagabbros which have partly turned into eclogitic form. Cover series unconformably overlying thebasement are divided into two units, in Palaeozoic and Mesozoic-Early Tertiary ages. The basement and coverseries were influenced by an effective Alpine contractional deformation and a regional metamorphism in Tertiarytime. Geological and geochronological data in the Menderes Massif, indicate the presence of three acidicmagmatic activities of i) Pan-African, ii) Triassic and iii) Miocene in ages. The acidic magmatics forming theprotolithes of Pan-African orthogneisses can be divided into three main types according to their textural andmineralogical compositions as; 1) Biotite orthogneiss, 2) Tourmaline leucocratic orhogneiss and 3) Amphiboleorthogneiss. The relations of primary granites of these orthogneisses present a clear intrusive contact relationshipamong them and with the metaclastics of Late Proterozoic age. The contact relationships show that theseorthogneiss types can be ordered as biotite orthogneisses, tourmaline leucocratic orthogneisses and amphiboleorthogneisses ranging from old to young, with respect to relative aging. Although there has been some problemsoriginating from the definition of samples dated in previous studies, it is noted that radiometric data mainly showa consistency with this relative relationship (biotite orthogneiss: 550-570 Ma; tourmaline leucocratic orthogneiss:541-547 Ma and amphibole orthogneiss: 531 Ma). These radiometric data indicate that different orthogneiss typesin the Massif are differentiated products of the same Late Proterozoic - Early Cambrian acidic magmatic activity.When the paleogeographical position of the Massif in Early Cambrian and the close temporal relation of the metamorphicstage of cover series and the acidic magmatism are assessed with the geochemical character oforthogneisses, this widespread magmatic activity with an average age of about 550 Ma which is related to thePan-African orogenesis can be attributed to proccesses of closure of the Mozambique Ocean, collision of Eastand West Gondwanaland, crustal thickening and partial melting of the lower crust. Triassic leucocraticorthogneisses constitutes the second effective acidic magmatic activity in the Menderes Massif with dimensionsof 6-7 km. These plutonic leucocratic orthogneisses in 6-7 km dimensions are exposed in Ödemiþ-Kiraz andDemirci-Gördes submassifs. They show well-preserved intrusive contact relationships with Late Proterozoicmetaclastics of the Pan-African basement and with metasediments of Late Palaeozoic cover series. Geochemicaldata show that protolithes of leucocratic orthogneisses are in calc alkaline and S type in character. Based onsingle zircon Pb/Pb evaporation method, these were radiometrically dated as ranging from 227 to 246 Ma. Theseages are interpreted as the age of emplacement of protolithes of orthogneisses in Middle Triassic. The existenceof Early-Middle Triassic magmatic activity is widely known not only in the Massif but also at the tectonical zonesof the Anatolides, at the Karaburun peninsula, in Cyclades and at the inner Hellenides. When the regionalcharacter of Triassic magmatic activities is considered, it is suggested that there is a close genetical relationshipbetween these leucocratic orthogneisses and Triassic magmatics. It is also considered that it can be attributed tothe opening of Neothethys Ocean.

The Menderes Massif exposing in the Western Anatolia substantially presents a complex tectonostratigraphyas a result of Late Alpine compressional tectonism. The lithostratigraphical succession of this crystallinecomplex can be divided into two units: 1- The Pan-African basement (core series) and 2-Palaeozoic - EarlyTertiary metasedimentary rocks (cover series). The Pan-African basement of the Menderes Massif is made up ofa Late Neoproterozoic metaclastic sequence consisting of paragneisses and conformably overlying micaschists.This high-grade metaclastic sequence is extensively migmatized and intruded by the syn- to post-Pan-Africangabbros and granitoids. The primary contact relationship between the core and cover series is a regional unconformityin character. The Palaeozoic (?Upper Devonian - Permian) cover units, which are cut by the intrusion ofTriassic leucocratic metagranites are consisted of phyllites, quartzites and marbles. The Mesozoic cover units arecharacterized by Triassic to Upper Cretaceous platform-type thick marbles at lower levels of the sequence. UpperCampanian - Upper Maastrichtian pelagic carbonates and the overlying Middle Paleocene - Eocene flysch-typeblocky unit constitute the uppermost units of cover series. Relic mineral assemblages observed in the PanAfricanbasement reveal a complex polyphase metamorphic evolution of this basement under granulite, eclogiteand amphibolite-facies conditions. The high temperature metamorphism developing under granulite facies ischaracterized by the presence of hypersthene type pyroxene. Pelitic granulites, orthopyroxene gneisses, orthopyroxeneparagneisses and metagabbroic / metanoritic rocks form typical granulite-facies relics observed in themassif. Geothermobarometric estimations characterize an average temperature of 730 °C and pressure of 6 kbarfor the granulite-facies metamorphism. By means of SHRIMP II method, clustering ages of 583±5.7 Ma weredated from the outer parts zircons in pelitic granulites which have no zoning but have overgrown under granulitefacies. High grade metamorphism relics in the Pan-African basement are characterized by eclogite and eclogiticmetagabbros. Fully recrystallized, fine grained massif eclogites, with non bearing relic texture belonging toprotolith are composed of 'omphacite (jd40-52) + garnet + clinozoisite + amphibole + quartz + rutile'. However; relictexture and minerals are extensively observed in metagabbros derived from eclogitic gabbros. The pressuretemperature(P-T) conditions of the Pan-African high-pressure metamorphism were estimated as 644°C with aminimum pressure of about 15 kbar, which corresponds to a burial depth of about 50 km. 206Pb/ 238U zircon agesobtained from eclogitic metagabbros by TIMS yield 529.9±22 Ma, reveal the high-pressure metamorphism asPan-African in age. The Barrowian type medium pressure metamorphism reaching up migmatization stage inwhich anatectic granites developed caused extensive retrogradations. Geothermobarometric estimates fromgarnet amphibolites, retrograded from eclogites indicate that this metamorphism developed under P/T conditionsof 7 kbar in pressure and 628°C in temperature. The crystallization ages of these anatectic granites range from551 to 540 Ma. They were generated by migmatization of paragneisses and reveal that this medium-pressureevent is related to the last stage of polyphase Pan-African metamorphism. All metamorphic ages obtained fromthe Pan-African basement are compatible with the latest stages of assemblage of Gondwana super continent. Itis considered that protoliths of paragneisses and schists of the Pan-African basement were deposited on apassive continental margin of a basin occurring between East and West Gondwana during the Late Proterozoictime (Mozambique Ocean). The Pan-African basement of the Menderes Massif was deeply buried and metamorphosedunder granulite, eclogite and amphibolite-facies conditions as a result of the closure of this basin andcollision of East and West Gondwana during Late Neoproterozoic time. Both core and cover series of theMenderes Massif were affected by an Alpine aged old regional metamorphism. In the Palaeozoic sequence of cover series, this metamorphism is characterized by a Barrowian type medium-pressure metamorphism. Thismetamorphism developed under greenschist to lower amphibolite-facies (6 kbar in pressure / 430-550 °C in temperature)and described by the occurrences of garnet, staurolite and kyanite (disthene) in phyllites. MesozoicEarlyTertiary cover series at the southern part of Çine submassif contain data associated with Alpine aged HP/LTmetamorphism. Carpholite-kyanite assemblage within Triassic quartz metaconglomerates shows a metamorphismunder a pressure of 10-12 kbar and temperature of 440 °C corresponding to a minimum depth of 30 km.So far, there has not been detected any data for an Alpine HP / LT metamorphism, neither in the Pan-Africanbasement nor in the Palaeozoic sequence of the Menderes Massif. Based on the fossil content obtained fromyoungest unit of the cover series and from the oldest non metamorphic sedimentary cover on the massif, theAlpine metamorphism can biostratigraphically be constrained into Eocene and Oligocene time interval. Fewisotopic data (37±1 Ma, Late Eocene Rb/Sr biotite age; 36±2 Ma, Middle Eocene Ar/Ar muscovite age; 43-37 Ma,Eocene Ar/Ar muscovite age) related to Alpine metamorphism are compatible with the related time interval. TheAlpine metamorphisms of tectonical zones belonging to Anatolides is substantially associated with the closure ofthe northern branch of Neothethys Ocean and with the collision in Paleogene. In such a tectonic model, thesegment of the Anatolide-Tauride platform corresponding to the Menderes Massif was subjected to intenseinternal imbrication during the subduction process of the northern branch of Neotethys and the following periodin which the continental collision occurred. The tectonical slices being formed were buried at different depths andmetamorphosed under varying conditions related with burial depths under the load of Afyon zone at north inEocene-Oligocene times, and of Lycian nappes passing south and of ophiolites.

The Menderes Massif, exposed in the Western Anatolia, is tectonically overlain to the north by theAfyon Zone and to the south by the Lycian Nappes. In the northwest, two high-pressure units, the CycladicComplex and overlying the Lycian Nappes, as well as the nappes of Ýzmir - Ankara Zone tectonically overlay theMenderes Massif. The metamorphic rock succession of the Massif can be divided into two main units: 1-PanAfricanbasement (core series) and 2-Palaeozoic - Early Tertiary metasedimentary rocks (cover series). The PanAfricanbasement shows a stratigraphy consisting of a partly migmatized metaclastic sequence and polymetamorphicbasic and acidic igneous rocks that intruded into these metaclastics. This metaclastic sequence, which iscomposed of paragneiss and conformably overlying schist units reaches a minimum thickness of eight kilometersand forms the oldest rocks of the Pan-African basement of the Menderes Massif. Field studies and geochronologicaldata suggest that the protoliths of the paragneisses are predominantly clastic sediments of lithareniticcomposition. Frequently, the paragneisses alternate and interfinger in all directions with micaschists andbiotite-albite schists, originating from mudstone and subarkosic sandstone, respectively. The paragneisses areconformably overlain by a schist unit. The originally gradual sedimentary contact is represented by a paragneissand schist intercalation. The schists are dominated by micaschists with biotite-albite schist layers, derived frommudstone and subarkose, respectively. In the Menderes Massif, the paragneisses are generally extensivelymigmatized. Widespread anatectic granites occur as irregular-shaped bodies with migmatized margins. Thedetrital zircons of the paragneisses yielded ages scattered between 610 - 2558 Ma. Detrital zircons of the schistunit of the Pan-African basement were dated at 592 - 3239 Ma. The intrusion ages of the orthogneiss showingclear intrusive contact relationship with metaclastic sequence range from 570 to 520 Ma. The granulite faciesmetamorphism of the paragneiss unit was dated at 583±5.7 Ma. These geochronological evidence and thecontact relationships clearly reveal that the deposition age of the protoliths of the metaclastic sequence of thePan-African basement can be constrained to Late Neoproterozoic between ca 590 - 580 Ma. The metaclasticsequence is intruded by large granitoid bodies and gabbroic stocks. The intrusion ages of the granitic precursorsnow represented by orthogneisses with changed mineralogical compositions and primary textures range from 520to 570 Ma with a major event at about 550 Ma. These granites, which can be divided into three main groups(biotite orthogneiss, amphibole orthogneiss and tourmaline leucocratic orthogneiss) are the products of apoly-phase Pan-African acidic magmatic activity that intruded the metaclastic sequence. They are syn- topost-metamorphic intrusions with respect to the Pan-African orogeny. The basic meta-igneous rocks occurring inthe Pan-African basement have gabbroic to noritic composition. They display massive cores and foliated marginsthat consist mainly of garnet amphibolites with relics of eclogites revealing the polymetamorphic history of thePan-African basement. Field evidence and radiometric age data indicate that the primary contact relationship between the Pan-African basement and the Palaeozoic cover series in the Menderes Massif was an unconformity(Supra-Pan-African unconformity) and the cover series were sourced from the Pan-African basement. Theprotoliths of the paragneiss and schist of the Pan-African basement were deposited on the passive continentalmargin of a basin occurring between East and West Gondwana during the Late Neoproterozoic time(Mozambique ocean). All the magmatic and metamorphic ages obtained from Pan-African basement coincide withthe closure of this ocean and the final assemblage of the Gondwana supercontinent during Late NeoproterozoicCambriantime.

The study presents U-Pb zircon ages for granitic gneiss and amphibolite from the Luzhenguan Complex (LZC) in northern part of the eastern Dabie Orogen and their geological significance. Two granitic gneisses and one amphibolite give protolith zircon U-Pb ages of 740 Ma and 725 Ma, respectively. The ages show that the LZC is composed mainly of Neoproterzoic acid and basic igneous rocks, suggesting that there is no Paleozoic active continental marginal rock association in the southern margin of the North China Block in northern part of the eastern Dabie Mountain. Based on the ages and combining the geological and geophysical analyses, the middle-low grade metamorphic rocks in the North Huiyang Belt (NHB) can be divided into three parts, which are the LZC composed mainly of the Neoproterzoic acid and basic igneous rocks, the Neoproterzoic Xianrechong Formation and Xiangyunzhai Formation and the Devonian Zhu- foan Formation and Pangjialing Formation of the Foziling Group, and the suture zone between the Yongtze Block and the North China Block is inferred to be thrust under the NHB.