Research Progress on Mechanisms in Regulating Anxiety-Related Neural Circuits

Anxiety is a common disease in the modern society which significantly affects people’s daily lives and function,thus it has become an increasingly highlighted issue.Anxiety is regulated by neural circuits in the brain.Therefore,the basal mechanism of anxiety has been studied,especially research based on the related neural circuits.For a long time,due to the limitations of science and technology,there was no breakthrough in research regarding anxiety.However,in recent years,due to the progress of technology,the research on anxiety neural circuits has made great progress.For example,the interaction among various brain regions,such as the central nucleus of the amygdala(CeA),the ventral tegmental area(VTA),the ventral hippocampus(vHPC),and so on.This article focuses on three brain regions:including BLA,BNST,and VTA,and illustrate their different roles and mechanisms in regulating anxiety.On this basis,this intensive study of anxiety will further promote the progress of anxiety research and provide therapeutic targets for the related treatment.

Ototoxic effects and mechanisms of loop diuretics

Over the past two decades considerable progress has been made in understanding the ototoxic effects and mechanisms underlying loop diuretics. As typical representative of loop diuretics ethacrynic acid or furosemide only induces temporary hearing loss, but rarely permanent deafness unless applied in severe acute or chronic renal failure or with other ototoxic drugs. Loop diuretic induce unique pathological changes in the cochlea such as formation of edematous spaces in the epithelium of the stria vascularis, which leads to rapid decrease of the endolymphatic potential and eventual loss of the cochlear microphonic potential, summating potential, and compound action potential. Loop diuretics interfere with strial adenylate cyclase and Nat/Kt-ATPase and inhibit the Na-K-2Cl cotransporter in the stria vascularis, however recent reports indicate that one of the earliest effects in vivo is to abolish blood flow in the vessels supplying the lateral wall. Since ethacrynic acid does not damage the stria vascularis in vitro, the changes in Nat/Kt-ATPase and Na-K-2Cl seen in vivo may be secondary effects results from strial ischemia and anoxia. Recent observations showing that renin is present in pericytes surrounding stria arterioles suggest that diuretics may induce local vasoconstriction by renin secretion and angiotensin formation. The tight junctions in the blood-cochlea barrier prevent toxic molecules and pathogens from entering cochlea, but when diuretics induce a transient ischemia, the barrier is temporarily disrupted allowing the entry of toxic chemicals or pathogens.

ENDOCOCHLEAR POTENTIAL AND POTASSIUM CONCENTRATION RECORDING IN MINIPIG COCHLEA

Objective To record the endocochlear potential (EP) and calculate potassium concentration [K+] in Minipig cochleae. Methods We used multi-barreled electrodes to measure the EP and the potential, [K + ]. EP and potassium electrode recording were made in 9 cochleae from 5 minipigs to get normal EP values. Results The average EP value in the cochlea from the minipigs was 77.3 ± 14 mV. The average [K+] for the minipigs was 147.1 ± 13 mM. Conclusions The EP and potential, [K + ] in minipigs are lower than in the human and rodents. This may be the reason why porcine ABR thresholds are slightly higher than humans and rodents.

Expression Patterns and Implications of LaminBl in Rat Cochleae

LaminB1,a major component of the nuclear lamina,is a potent regulator of cellular proliferation and senescence and also known to be essential for neuronal migration and brain development.However,the expression patterns of LaminB1 in the rat cochleae are still not fully revealed.Utilizing immunofluorescence.Western blotting,and quantitative real-time PCR,we identified the distribution and expression of LaminB1 in the rat cochleae.Immunofluorescence staining indicated that LaminBl was mainly localized in the auditory hair cells(HCs),spiral ganglion cells(SGC),stria vascularis(STV,including spiral ligament),Reissner's membrane(RM),and limbus laminae spiralis(LLS).Western blotting analysis illustrated that the distribution of LaminBl in rat cochleae was characterized by tissue specificity.The LaminB1 protein was expressed more in SGC and basilar membrane(BM)than in STV.Meanwhile,the mRNA expression of LaminB1 displayed difference in cochlear tissues.These observations preliminarily revealed the expression patterns of LaminB1,providing a theoretical basis for further study on the role of LaminB1 in auditory function.

The Ultrastructural Characteristics of the Stria Vascularis, Spiral Prominence and Spiral Ligament in Guinea Pigs

The mean length of the stria vascularis (SV) and the basilar membrane of four normalguinea pigs measured by means of surface preparation was 21.11 mm and 19. 90 mm respectively,and the mean width of their apical turns of SV and the turns of the cochlear basis was 0. 44 mmand 0. 86 mm respectively. The ultrastructure of SV, spiral ligament (SL) and spiral prominence(SP) of both ears of eight guinea pigs were observed by scanning electron microscopy(SEM) andtransmission electron microsoopy(TEM). There were a large number of coated vesicles in thesupranuclear region of SV, some opened to the endolymph. A great number of folding cytoplasmicprojections were filled with small vesicles The capillary network was extremely rich indicating thatthe endolymph could be secreted and absorbed by SV. The cellular conjunction in the SV. SL andSP formed an effective barrier. It has not been proved in this study that the melanin offers resistanceto acoustic stimulation.

ERG CHARACTERISTICS OF CONGENITAL STATIONARY NIGHT BLINDNESS

The ERGs of 9 cases (18 eyes) of congenital stationary night blindness with normal fundi or myopia were tested. All eyes showed nonrecordable rod ERG and cone ERG with normal a-wave. Scotopic mixed ERGs were of the negative type in 7 eyes and of the ssubnormat type in 11 eyes. The b/a ratio was reduced in all eyes. The ERG characteristics are useful for the classification, estimation of the probable location of the lesion, and differential diagnosis of the disease.

WORLD NEWS IN BRIEF(February 1-15, 1988)

Zhao Ziyang, Generai Secretary of the Chinese Communist Party, made a televised speech through satellite on February 2 at the 1988 meeting of the World Economic Forum held in Davos, Switzerland. The Palestinian Liberation Organization on February 2 in Tunis denounced the US veto of a UN Security Council

耳蜗血管纹产生耳蜗内电位的机理

耳蜗内淋巴具有独特的离子成分,以及相对于外淋巴+80mv^+90mv的耳蜗内电位。血管纹对维持耳蜗内环境的稳定有重要作用,它在向内淋巴转运钾离子的过程中产生耳蜗内电位。本文对血管纹产生耳蜗内电位的各种相关机理的研究进展进行综述。

内耳损伤的修复与再生

噪声、药物、重金属等因素可导致内耳损伤。内耳损伤的研究发现，不同机制不同类型的损伤通常始发于内耳的特定区域。本文集中探讨内耳损伤后，对特定区域的干预以帮助内耳损伤后的修复与再生。

Testicular descent and fixation through a scrotal stria incision for the treatment of palpable cryptorchidism in children aged<3 years:10-year experience with 1034 cases

This study was performed to summarize our clinical experience with testicular descent and fixation through a scrotal stria incision for the treatment of palpable cryptorchidism in children.This study included 1034 children with palpable cryptorchidism from March 2009 to March 2019.A scrotal stria incision was used to perform testicular descent and fixation.Overall,1020 children successfully underwent surgical testicular descent and fixation through a scrotal stria incision,and 14 patients underwent conversion to inguinal incision surgery.All patients were discharged 1-2 days after the operation.During hospitalization and follow-up,55 patients developed complicationsy including 10 patients with testicular retraction,7 with poor healing of the incision,and 38 with a scrotal hematoma.No patients developed testicular atrophy,an in direct ingui nal hernia,or a hydrocoele.Testicular descent and fixation through a scrotal stria incision for the treatment of palpable cryptorchidism in children is safe and feasible in well-selected cases.This method has the advantages of no scarring and a good cosmetic effect.

Inactivation of the bed nucleus of the stria terminalis suppresses the innate fear responses of rats induced by the odor of cat urine

In this study,we investigated whether two brain regions,the bed nucleus of the stria terminalis(BNST)and the basolateral amygdala(BLA),affected male rats(Rattus norvigicus)ability to innately discriminate between a predator odor(cat urine)and female rat urine.Muscimol,a GABAa receptor agonist,was bilaterally microinjected into either the BNST or BLA of rats through

Abnormal augmentation of the receptor potential and morphology changes of guinea pig's cochlea induced by Cisplatin

To investigate the characteristics of cochlear microphonic (CM), summating potential (SP) and compound action potential (CAP) and morphology changes of outer hair cells (OHCs) and inner hair cells (IHCs) after OHCs were selectively damaged by acute cochlear perfusion of cisplatin. Dynamic changes of CM, SP and CAP were recorded from the scala media of the third turn of the guinea pig's cochlea during Cisplatin perfusion into the whole cochlea for 2 hours. The results indicated that after one hour of the perfusion, the amplitude of CM, SP and CAP decreased at stimulus intensity < 60 dB SPL, while the amplitude increased at stimulus intensity > 70 dB SPL, as compared to those examined before perfusion of Cisplatin (the average of CM increased by 3.6 mV at 90 dB SPL, average of SP increased by 1.6 mV at 120 dB SPL, average of CAP increased by 0.23 mV at 90dB SPL). After two hours of perfusion, the amplitude of CM, SP and CAP decreased in all stimulus intensities. The staining of Succinic Dehydrogenase (SDH) was weak in OHCs, while the stain ing of IHCs remained normal. transmission electron microscopic examination of organ of Corti showed varieties of morphological changes in OHCs, such as nucleus chromosome disappear, mitochondria denaturalization and number reduction, while the structure of IHC appeared normal. SDH staining showed normal staining pattern in both IHCs and OHCs when the cochlea was perfused with artificial perilymph for 2 hours. The abnormal augmentation phenomenon of CM and SP may be induced by the abnormal control of Ca++ in IHCs and OHCs. The abnormal augmentation of CAP suggests that the suppression effects of OHCs and efferent neurotransmitter on IHCs and afferent neurotransmitter may be reduced after OHCs damaged.

DISTRIBUTION AND LOCATION OF IMMUNOREACTIVE ATRIAL NATRIURETIC PEPTIDES IN COCHLEAR STRIA VASCULARIS OF GUINEA PIG

The distribution and location of atrial natriuretic peptides(ANP) in the cochlear stria vaseularis of normal guinea pigswere studied to find out regional regulating factors of cochlearblood flow (CBF) and productive foundation of cochlearendolymph by ABC immunocytochemistry and immunoele-ctronmicroscopy. The ANP-IR products were seen in the striavascularis of the 1-4 turns of the lateral wall of the cochlea,more markedly along its margin; and were negative in the spi-ral ligaments. Immunoelectronmicroscopically, a plenty ofsphericals of 250-350nm in diameter were noted in thecytoplasm of marginal and intermediate cells, but few in thebasal cells. The results suggest that the cochlear striavascularis had the function of secreting ANP in the guinea pig.

Abnormal expression of connexin 36 plays a role in the pathogenesis of levodopa induced dyskinesia in rat model of Parkinson's disease

Objective To expore whether gap junction disturbances are involved in the pathogenesis of levodopa-induced dyskinesia(LID).Methods The hemi-parkinsonian(PD)rat was treated intraperitoneally with L-dopa methylester(20 mg/kg)and benserazid(10 mg/kg)for21 days and abnormal involuntary movement was evaluated to establish LID rat model.The experimental animals were divided into three groups:LID group,PD