Clinical Analysis of Myocardial Injury in Highlanders with Pulmonary Hypertension.

Background: Pulmonary hypertension (PH) is a prevalent adverse cardiovascular event at high-altitude environments. Prolonged exposure to high altitudes may result in myocardial injury, which is associated with poor clinical outcomes. This study aims to investigate the clinical characteristics of myocardial injury in patients with PH at high altitude. Methods: Consecutive patients admitted to a general tertiary hospital at the altitude of 3,650 m were selected into this retrospective study. Clinical and biochemical data were collected, as well as based on cardiac troponin I (cTnI) and echocardiography, patients were divided into myocardial injury group and non-myocardial injury group. Results: A total of 231 patients were enrolled, among whom 29 (12.6%) had myocardial injury. We found that body mass index, left ventricular end-diastolic dimension, and serum level of creatine kinase-MB (CK-MB) in myocardial injury group were significantly higher than non-myocardial injury group. Spearman correlation analysis revealed that cTnI has a significant positive correlation with CK-MB and lactic dehydrogenase instead of aspartate aminotransferase. A receiver operating characteristic curve was drawn to demonstrate that CK-MB could significantly predict the occurrence of myocardial injury with an area under the curve of 0.749, and a level of 3.035 (sensitivity = 59.3%, specificity = 90.5%) was optimal cutoff value. Conclusion: The incidence of myocardial injury in highlanders with PH is significant. CK-MB, as a convenient and efficient marker, has been found to be closely associated with cTnI and plays a predictive role in the occurrence of myocardial injury with PH in individuals exposed to high altitude.

Chronic restraint stress induces depression-like behaviors and alterations in the afferent projections of medial prefrontal cortex from multiple brain regions in mice.

INTRODUCTION: The medial prefrontal cortex (mPFC) forms output pathways through projection neurons, inversely receiving adjacent and long-range inputs from other brain regions. However, how afferent neurons of mPFC are affected by chronic stress needs to be clarified. In this study, the effects of chronic restraint stress (CRS) on the distribution density of mPFC dendrites/dendritic spines and the projections from the cortex and subcortical brain regions to the mPFC were investigated. METHODS: In the present study, C57BL/6 J transgenic (Thy1-YFP-H) mice were subjected to CRS to establish an animal model of depression. The infralimbic (IL) of mPFC was selected as the injection site of retrograde AAV using stereotactic technique. The effects of CRS on dendrites/dendritic spines and afferent neurons of the mPFC IL were investigaed by quantitatively assessing the distribution density of green fluorescent (YFP) positive dendrites/dendritic spines and red fluorescent (retrograde AAV recombinant protein) positive neurons, respectively. RESULTS: The results revealed that retrograde tracing virus labeled neurons were widely distributed in ipsilateral and contralateral cingulate cortex (Cg1), second cingulate cortex (Cg2), prelimbic cortex (PrL), infralimbic cortex, medial orbital cortex (MO), and dorsal peduncular cortex (DP). The effects of CRS on the distribution density of mPFC red fluorescence positive neurons exhibited regional differences, ranging from rostral to caudal or from top to bottom. Simultaneously, CRS resulted a decrease in the distribution density of basal, proximal and distal dendrites, as well as an increase in the loss of dendritic spines of the distal dendrites in the IL of mPFC. Furthermore, varying degrees of red retrograde tracing virus fluorescence signals were observed in other cortices, amygdala, hippocampus, septum/basal forebrain, hypothalamus, thalamus, mesencephalon, and brainstem in both ipsilateral and contralateral brain. CRS significantly reduced the distribution density of red fluorescence positive neurons in other cortices, hippocampus, septum/basal forebrain, hypothalamus, and thalamus. Conversely, CRS significantly increased the distribution density of red fluorescence positive neurons in amygdala. CONCLUSION: Our results suggest a possible mechanism that CRS leads to disturbances in synaptic plasticity by affecting multiple inputs to the mPFC, which is characterized by a decrease in the distribution density of dendrites/dendritic spines in the IL of mPFC and a reduction in input neurons of multiple cortices to the IL of mPFC as well as an increase in input neurons of amygdala to the IL of mPFC, ultimately causing depression-like behaviors.

The mediating role of trust in government in intergenerational transmission of fertility intentions.

China's one-child policy was in effect from 1982 to 2015. However, the literature examining the association between people's trust in local government and intergenerational transmission of fertility intentions is scarce. To fill this gap, we investigated the impact of individuals' sibship size on their ideal number of children, the mediating effect of their trust in local government on the issue of fertility between two successive generations, and the moderating effect of education level on sibship size related to trust in local governments. Based on the 2019 Chinese Social Survey data, 2,340 respondents aged 18-35 participated in the analysis. The results showed that (i) individuals' number of siblings significantly positively predicted their ideal number of children; (ii) individuals' number of siblings significantly negatively predicted their trust in the local government, which in turn significantly negatively influenced fertility intentions; (iii) the mediating mechanism was significant in residents with higher levels of education, but not in people with lower degrees of education. Fertility-boosting incentives can prioritize couples who are the only child in their family. It is necessary for local governments to improve their credibility and strengthen their pregnancy-related communication with groups with higher levels of education.

The association between future self-continuity and problematic mobile video gaming among Chinese college students: the serial mediation of consideration of future consequences and state self-control capacity.

BACKGROUND: To explore the relationship between future self-continuity and problematic mobile video gaming among Chinese college students and to examine the serial mediation of consideration of future consequences and state self-control capacity on the association between future self-continuity and problematic mobile video gaming, based on Identity-Based Motivation Theory. METHODS: The Problematic Mobile Video Gaming Scale, Future Self-continuity Scale, Consideration of Future Consequences Scale, and Short Version of State Self-control Capacity Scale were administered to a sample comprising 800 college students (338 males accounting for 42.3%). Multivariate analysis and latent variables analysis were utilized to explore the separate mediating role consideration of future consequences and state self-control capacity played in the association between future self-continuity and problematic mobile video gaming, and their serial mediation also was investigated. The Bootstrap method was employed to test the significance of these mediation effects. RESULTS: The negative association between future self-continuity and problematic mobile video gaming was moderately found. Students with increased consideration of future consequences from higher levels of future self-continuity have decreased their problematic mobile video gaming. Future self-continuity significantly positively predicted state self-control capacity, which in turn significantly negatively predicted problematic mobile video gaming. The serial mediation was also found. CONCLUSION: The findings revealed why differences in identification with the current and future selves become influencing factors in problematic mobile video gaming. This study observed the mediating role that consideration of future consequences and state self-control capacity play in the association between future self-continuity and problematic mobile video gaming.

Relationship between epicardial adipose tissue measured by computed tomography and premature ventricular complexes originating from different sites.

AIMS: This study aims to explore the association between the features of epicardial adipose tissue (EAT) in different zones and premature ventricular complexes (PVCs) originating from different sites by computed tomography (CT). METHODS AND RESULTS: A total of 136 patients who underwent radiofrequency ablation for PVCs were incorporated in this study. One hundred and thirty-six matched controls were included in this study using the case-control method (1:1 matching). PVCs were classified into four subgroups: (1) right ventricular outflow tract (RVOT-PVCs), (2) non-RVOT of the right ventricle (RV-PVCs), (3) left ventricular outflow tract (LVOT-PVCs), and (4) non-LVOT of the left ventricle (LV-PVCs). The volume and density of EAT were quantified by CT. Patients with PVCs had a significantly higher volume and lower density of EAT than the controls (P < 0.001). The LVOT-PVCs and LV-PVCs had a higher left ventricle periventricular EAT volume (LV-EATv) proportion (P < 0.05). The right ventricle periventricular EAT volume (RV-EATv) proportion was higher in ROVT-PVCs and LVOT-PVCs (P < 0.05). RVOT-PVC patients had a higher volume ratio and a smaller density differential (P < 0.05). Patients with LVOT-PVCs had a lower volume ratio and the LV-PVCs showed a greater density differential (P < 0.05). CONCLUSION: Higher volume and lower density of EAT were significantly associated with frequent PVCs. The RVOT-PVC patients had a higher volume ratio and a smaller density differential. The LVOT-PVCs had a lower volume ratio and the LV-PVCs showed a greater density differential. These suggest a link between EAT structural properties and PVCs and a potential role for regional EAT in the development of PVCs.

Health and Wellness Tourists' Motivation and Behavior Intention: The Role of Perceived Value.

In recent years, with the rapid change of people's health concept, health and wellness tourism has shown a vigorous development trend. However, existing literature has been lacking on travelers' behavioral intentions, influenced by their motivation in health and wellness tourism. To fill in this gap, we designed scales of tourists' behavioral intention and motivation in health and wellness tourism and investigated the aforementioned effects, with a sample of 493 visitors who have traveled in health and wellness tourism. Factor analysis and structural equation models were applied to explore the relations among motivation, perceived value, and behavioral intention in health and wellness tourism. The results indicate that health and wellness tourists' motivation significantly positively predicts their behavior intentions. Travelers' perceived value of health and wellness tourism significantly partially mediates the associations between their behavioral intention and escape motivation, attractive motivation, environmental motivation, as well as interpersonal motivation. No empirical evidence supports the mediating role of perceived value in the correlation between consumption motivation and behavioral intention. Health and wellness tourism industries are encouraged to meet the intrinsic motivation of travelers and make them perceive the value of this kind of tourism, which in turn promotes tourists' choice, evaluation, and satisfaction of health and wellness tourism.

Male antiphonal calls and phonotaxis evoked by female courtship calls in the large odorous frog (Odorrana graminea).

Acoustic communication plays a vital role in frog reproduction. In most anuran species, long-distance sound communication is one-way from males to females; during the reproductive season, males produce species-specific advertisement calls to attract gravid females, and females are generally silent but perform phonotactic movements that lead to amplexus. One exception is the concave-eared torrent frog (Odorrana tormota). In this species, females produce courtship calls that elicit antiphonal vocalizations by males, followed by precise phonotactic movements. The large odorous frog O. graminea (previously Odorrana livida) in southern China is subject to the same environmental constraints as O. tormota, with which it is sympatric; it is unclear whether their sound communication is one-way or bidirectional. Here, we provide the first data on female O. graminea vocalizations and their functions. Using playbacks of female calls, we conducted acoustic behavioral experiments in the laboratory in response to which males emitted single- or multi-note antiphonal calls with a varying fundamental frequency. Moreover, they were attracted to female call playbacks, exhibiting precise phonotaxis. The female courtship call-male response interaction thus forms a duet between partners of a receptive pair. These results demonstrate that this unique communication system likely reflects an adaptation to an environment in which short-distance communication is at a premium given the high levels of ambient noise.

WiSE CRT Is Beneficial for Heart Failure Patients as a Rescue Therapy: Evidence From a Meta-Analysis.

Background: Leadless endocardial left ventricular (LV) pacing resynchronization therapy is a novel solution for patients with heart failure (HF) in whom conventional cardiac resynchronization therapy (CRT) failed. Methods: PubMed and the Cochrane Library were searched for relevant cohort studies. Clinical outcomes of interest such as ejection fraction (EF), QRS duration (QRSd), and left ventricular end-systolic volume (LVESV) were extracted and analyzed. Results: Five studies involving 175 HF patients for WiSE CRT were included, and patients were followed-up for 6 months. The implanted success rate ranged from 76.5 to 100%. WiSE CRT resulted in significantly narrower QRSd [mean difference (MD): -38.21 ms, 95% confidence interval (CI): -44.36 to -32.07, p < 0.001], improved left ventricular ejection fraction (MD: 6.07%, 95% CI: 4.43 to 7.71, I2 = 0%, p < 0.001), reduced left ventricular end-systolic volume (MD: -23.47 ml, 95% CI: -37.18 to -9.13, p < 0.001), and reduced left ventricular end-diastolic volume (MD: -24.02 ml, 95% CI: -37.01 to -11.03, p = 0.02). Conclusion: Evidence from current studies suggests that leadless endocardial LV pacing resynchronization is effective for HF patients who failed conventional CRT or needed a device upgrade, and it may be an interesting rescue therapy.

Estradiol attenuates chronic restraint stress-induced dendrite and dendritic spine loss and cofilin1 activation in ovariectomized mice.

Ovarian hormone deprivation is associated with mood disorders, such as depression, and estradiol therapy is significantly more effective than placebos in treating major depression associated with menopause onset. However, the effect of estradiol on neuronal plasticity and its mechanisms remain to be further elucidated. In this study, behavioral assessments were used to examine the antidepressant effect of estradiol in ovariectomized (OVX) B6.Cg-TgN (Thy-YFP-H)-2Jrs transgenic mice on chronic restraint stress (CRS)-induced dendrite and dendritic spine loss; Yellow fluorescent protein (YFP) is characteristically expressed in excitatory neurons in transgenic mice, and its three-dimensional images were used to evaluate the effect of estradiol on the density of different types of dendritic spines. Quantification and distribution of cofilin1 and p-cofilin1 were determined by qPCR, Western blots, and immunohistochemistry, respectively. The results revealed that treatment with estradiol or clomipramine significantly improved depression-like behaviors. Estradiol treatment also significantly upregulated the dendritic density in all areas examined and increased the density of filopodia-type, thin-type and mushroom-type spines in the hippocampal CA1 and elevated the thin-type and mushroom-type spine density in the PFC. Consistent with these changes, estradiol treatment significantly increased the density of p-cofilin1 immunopositive dendritic spines. Thus, these data reveal a possible estradiol antidepressant mechanism, in that estradiol promoted the phosphorylation of cofilin1 and reduced the loss of dendrites and dendritic spines, which of these dendritic spines include not only immature spines such as filopodia-type, but also mature spines such as mushroom-type, and attenuated the depression-like behavior.

The Antidepressant Effects of Resveratrol are Accompanied by the Attenuation of Dendrite/Dendritic Spine Loss and the Upregulation of BDNF/p-cofilin1 Levels in Chronic Restraint Mice.

Depression afflicts more than 300 million people worldwide, but there is currently no universally effective drug in clinical practice. In this study, chronic restraint stress (CRS)-induced mice depression model was used to study the antidepressant effects of resveratrol and its mechanism. Our results showed that resveratrol significantly attenuated depression-like behavior in mice. Consistent with behavioral changes, resveratrol significantly attenuated CRS-induced reduction in the density of dendrites and dendritic spines in both hippocampus and medial prefrontal cortex (mPFC). Meanwhile, in hippocampus and mPFC, resveratrol consistently alleviated CRS-induced cofilin1 activation by increasing its ser3 phosphorylation. In addition, cofilin1 immunofluorescence distribution in neuronal inner peri-membrane in controls, and cofilin1 diffusely distribution in the cytoplasm in CRS group were common in hippocampus. However, the distribution of cofilin1 in mPFC was reversed. Pearson's correlation analysis revealed that there was a significant positive correlation found between the sucrose consumption in sucrose preference test and the dendrite density in multiple sub-regions of hippocampus and mPFC, and a significant negative correlation between the immobility time in tail suspension test and the dendrite/dendritic spine density in several different areas of hippocampus and mPFC. P-cofilin1 was significantly positively correlated with the overall dendritic spine density in mPFC as well as with the overall dendrite density or BDNF in the hippocampus. Our results suggest that the BDNF/cofilin1 pathway, in which cofilin1 may be activated in a brain-specific manner, was involved in resveratrol's attenuating the dendrite and dendritic spine loss and behavioral abnormality.

RhoA/Rock2/Limk1/cofilin1 pathway is involved in attenuation of neuronal dendritic spine loss by paeonol in the frontal cortex of D-galactose and aluminum­induced Alzheimer's disease­like rat model.

Alzheimer's disease (AD) has become the most prevalent neurodegenerative disorder. Given the pathogenesis of AD is unclear, there is currently no drug approved to halt or delay the progression of AD. Therefore, it is pressing to explore new targets and drugs for AD. In China, polyphenolic Chinese herbal medicine has been used for thousands of years in clinical application, and no toxic effects have been reported. In the present study, using D­galactose and aluminum­induced rat model, the effects of paeonol on AD were validated via the Morris water maze test, open field test, and elevated plus maze test. Neuronal morphology in frontal cortex was assessed using ImageJ's Sholl plugin and RESCONSTRUCT software. RhoA/Rock2/Limk1/cofilin1 signaling pathway­related molecules were determined by Western blotting. Cofilin1 and p­cofilin1 were analyzed by immunofluorescence. Results showed that pre­treatment with paeonol attenuated D­galactose and aluminum­induced behavioral dysfunction and AD­like pathological alterations in the frontal cortex. Accompanied by these changes were the alterations in the dendrite and dendritic spine densities, especially the mushroom­type and filopodia­type spines in the apical dendrites, as well as actin filaments. In addition, the activity and intracellular distribution of cofilin1 and the molecules RhoA/Rock2/Limk1 that regulate the signaling pathway for cofilin1 phosphorylation have also changed. Our data suggests that paeonol may be through reducing Aß levels to alleviate the loss of fibrillar actin and dendrites and dendritic spines via the Rho/Rock2/Limk1/cofilin1 signaling pathway in the frontal cortex, and ultimately improving AD­like behavior.

Dynamic Evaluation Indices in Spatial Learning and Memory of Rat Vascular Dementia in the Morris Water Maze.

The Morris water maze (MWM) is widely used to evaluate rodent spatial learning and memory. However, current evaluation measures are not comprehensive because there is a wide distribution in the measured response. Utilizing the graph cognition hypothesis, we proposed four new deviation indices to evaluate cognitive function in the MWM that compared the optimal swim track to the actual track taken. These include the sum of the lateral deviation vectors, the sum of the offset angles, the sum of the correction vectors, and the sum of the lateral deviation vectors to the initial optimal route. We compared the four new deviation indices to the classically used escape latency measures in a vascular dementia model and demonstrated a higher consistency in the normal distribution between the vascular dementia group and the control rats. Further, the new measures displayed higher sensitivity and specificity compared to what escape latency displayed in the Monte Carlo simulation. From the receiver operating characteristic curve, the diagnostic values of the new deviation indices are higher than those of escape latency. Therefore, including these new evaluation indices in MWM experiments provided a more effective analysis of cognitive function compared to using escape latency.

The Lombard effect in male ultrasonic frogs: Regulating antiphonal signal frequency and amplitude in noise.

Acoustic communication in noisy environments presents a significant challenge for vocal animals because noise can interfere with animal acoustic signals by decreasing signal-to-noise ratios and masking signals. Birds and mammals increase call intensity or frequency as noise levels increase, but it is unclear to what extend this behavior is shared by frogs. Concave-eared torrent frogs (Odorrana tormota) have evolved the capacity to produce various calls containing ultrasonic harmonics and to communicate beside noisy streams. However, it is largely unclear how frogs regulate vocalization in response to increasing noise levels. We exposed male frogs to various levels of noise with playback of conspecific female courtship calls and recorded antiphonal signals and spontaneous short calls. Males were capable of rapidly adjusting fundamental frequency and amplitude of antiphonal signals as noise levels increased. The increment in fundamental frequency and amplitude was approximately 0.5 kHz and 3 dB with every 10 dB increase in noise level, indicating the presence of noise-dependent signal characteristics. Males showed the noise-tolerant adaption in response to female calls in noise level from 40 to 90 dB SPL. The results suggest that the noise-dependent signal characteristics in O. tormota have evolved as a strategy to cope with varying torrent noise.

Little effect of natural noise on high-frequency hearing in frogs, Odorrana tormota.

Ambient noise influences acoustic communication in animals. The concave-eared frogs (Odorrana tormota) produce high-frequency sound signals to avoid potential masking from noise. However, whether environmental noise has effect on the high-frequency hearing of frogs is largely unclear. By measuring the auditory evoked near-field potentials (AENFPs) from the torus semicircularis of the midbrain at frequencies 1-23 kHz in the presence of three noise levels, we found no significant difference in the peak-to-peak amplitude, threshold and latency of AENFP between low-level (35 dB SPL) background noise and mid-level (65 dB SPL) broadcast natural noise. For a natural noise level of 85 dB SPL, AENFP amplitude decreased and threshold and latency increased at frequencies 3-13 kHz. Spike counts evoked by stimuli at the best excitatory frequency under 85 dB SPL natural noise exposure were lower in 7-kHz CF neurons than in exposures to 35 and 65 dB SPL noise. However spike counts were similar for 14- and 20-kHz CF neurons at the three exposure levels. These findings indicate that environmental noise does not mask the responses of high-frequency tuned auditory neurons, and suggest that the acoustic communication system of O. tormota is efficiently adapted to noisy habitats.

Auditory sexual difference in the large odorous frog Odorrana graminea.

Acoustic communication is an important behavior in frog courtship. Male and female frogs of most species, except the concave-eared torrent frog Odorrana tormota, have largely similar audiograms. The large odorous frogs (Odorrana graminea) are sympatric with O. tormota, but have no ear canals. The difference in hearing between two sexes of the frog is unknown. We recorded auditory evoked near-field potentials and single-unit responses from the auditory midbrain (the torus semicircularis) to determine auditory frequency sensitivity and threshold. The results show that males have the upper frequency limit at 24 kHz and females have the upper limit at 16 kHz. The more sensitive frequency range is 3-15 kHz for males and 1-8 kHz for females. Males have the minimum threshold at 11 kHz (58 dB SPL), higher about 5 dB than that at 3 kHz for females. The best excitatory frequencies of single units are mostly between 3 and 5 kHz in females and at 7-8 kHz in males. The underlying mechanism of auditory sexual differences is discussed.

Inner ear morphological correlates of ultrasonic hearing in frogs.

Three species of anuran amphibians (Odorrana tormota, Odorrana livida and Huia cavitympanum) have recently been found to detect ultrasounds. We employed immunohistochemistry and confocal microscopy to examine several morphometrics of the inner ear of these ultrasonically sensitive species. We compared morphological data collected from the ultrasound-detecting species with data from Rana pipiens, a frog with a typical anuran upper cut-off frequency of ∼3 kHz. In addition, we examined the ears of two species of Lao torrent frogs, Odorrana chloronota and Amolops daorum, that live in an acoustic environment approximating those of ultrasonically sensitive frogs. Our results suggest that the three ultrasound-detecting species have converged on small-scale functional modifications of the basilar papilla (BP), the high-frequency hearing organ in the frog inner ear. These modifications include: 1. reduced BP chamber volume, 2. reduced tectorial membrane mass, 3. reduced hair bundle length, and 4. reduced hair cell soma length. While none of these factors on its own could account for the US sensitivity of the inner ears of these species, the combination of these factors appears to extend their hearing bandwidth, and facilitate high-frequency/ultrasound detection. These modifications are also seen in the ears of O. chloronota, suggesting that this species is a candidate for high-frequency hearing sensitivity. These data form the foundation for future functional work probing the physiological bases of ultrasound detection by a non-mammalian ear.

Large odorous frogs (Odorrana graminea) produce ultrasonic calls.

We present the first data on the vocalizations of large odorous frogs (Odorrana graminea, previously Odorrana livida), from southern China. The males produce diverse broadband signals most of which contain ultrasonic harmonics. Six basic call-types were identified based on the number of call notes, fundamental frequency, call/note duration, frequency modulation patterns and spectral composition. O. graminea is one of only a few non-mammalian vertebrates able to detect ultrasound, but its tympanic membranes are not recessed. These results should stimulate further studies to provide new insights into the mechanisms underlying high-frequency communication in anurans.

Columnar and layer-specific representation of spatial sensitivity in mouse primary auditory cortex.

The primary auditory cortex (AI) is implicated in coding sound location, as revealed by behavior-lesion experiments, but our knowledge about the functional organization and laminar specificity of neural spatial sensitivity is still very limited. Using single-unit recordings in mouse AI, we show that (i) an inverse relationship between onset latency and spike count is consistently observed when all the azimuthal points are taken; (ii) a substantial proportion of penetrations perpendicular to the AI surface showed columnar organization of best azimuths; (iii) the preferred azimuth range of AI neurons demonstrated layer-specific distribution pattern. Our findings suggest that similar to other response properties, the manner of sound space information processing in the auditory cortex is also layer dependent.

Ultrasonic frogs show extraordinary sex differences in auditory frequency sensitivity.

Acoustic communication has an important role in the reproductive behaviour of anurans. Although males of the concave-eared frog (Odorrana tormota) have shown an ultrasonic communication capacity adapted to the intense, predominately low-frequency ambient noise from local streams, whether the females communicate with ultrasound remains unclear. Here we present evidence that females exhibit no ultrasonic sensitivity. Acoustic playback experiments show that the calls from male evoke phonotaxis and vocal responses from gravid females, whereas the ultrasonic components (frequencies above 20 kHz) of the calls do not elicit any phonotaxis or vocalization in the females. Electrophysiological recordings from the auditory midbrain reveal an upper frequency limit at 16 kHz in females. Laser Doppler vibrometer measurements show that the velocity amplitude of the tympanic membranes peaks at 5 kHz in females and at ∼7 kHz in males. The auditory sex differences in O. tormota imply that ultrasonic hearing has evolved only in male anurans.

Ultrasound-evoked immediate early gene expression in the brainstem of the Chinese torrent frog, Odorrana tormota.

The concave-eared torrent frog, Odorrana tormota, has evolved the extraordinary ability to communicate ultrasonically (i.e., using frequencies > 20 kHz), and electrophysiological experiments have demonstrated that neurons in the frog's midbrain (torus semicircularis) respond to frequencies up to 34 kHz. However, at this time, it is unclear which region(s) of the torus and what other brainstem nuclei are involved in the detection of ultrasound. To gain insight into the anatomical substrate of ultrasound detection, we mapped expression of the activity-dependent gene, egr-1, in the brain in response to a full-spectrum mating call, a filtered, ultrasound-only call, and no sound. We found that the ultrasound-only call elicited egr-1 expression in the superior olivary and principal nucleus of the torus semicircularis. In sampled areas of the principal nucleus, the ultrasound-only call tended to evoke higher egr-1 expression than the full-spectrum call and, in the center of the nucleus, induced significantly higher egr-1 levels than the no-sound control. In the superior olivary nucleus, the full-spectrum and ultrasound-only calls evoked similar levels of expression that were significantly greater than the control, and egr-1 induction in the laminar nucleus showed no evidence of acoustic modulation. These data suggest that the sampled areas of the principal nucleus are among the regions sensitive to ultrasound in this species.