Antennae sense heat stress to inhibit mating and promote escaping in Drosophila females

Environmental stress is a major factor that affects courtship behavior and evolutionary fitness. Although mature virgin females of Drosophila melanogaster usually accept a courting male to mate, they may not mate under stressful conditions. Above the temperature optimal for mating (20–25?°C), copulation success of D. melanogaster declines with increasing temperature although we observed vigorous courtship attempts by males, and no copulation takes place at temperatures over 36?°C. We attempted to identify the sensory pathway for detecting heat threat that drives a female to escape rather than to engage in mating that detects hot temperature and suppresses courtship behavior. We found that the artificial activation of warmth-sensitive neurons (‘hot cells’) in the antennal arista of females completely abrogates female copulation success even at permissive temperatures below 32?°C. Moreover, mutational loss of the GR28b.d thermoreceptor protein caused females to copulate even at 36?°C. These results indicate that antennal hot cells provide the input channel for detecting the high ambient temperature in the control of virgin female mating under stressful conditions.     

The impact of experimental diabetes mellitus in rats on glomerular capillary number and sizes

Summary The structural counterpart of the increased glomerular filtration found in acute diabetes mellitus and experimental diabetes has been ascribed to the increased glomerular filtration surface. Using modern design-based stereological methods and light microscopy on perfusionfixed rat kidneys the average total surface area of capillaries per glomerulus in control rats was 291±42 10^–3 mm² (±SD) increasing to 383±55 10^–3 mm² in 10-day-diabetic rats. There was a further increase to 469±70 10^–3 mm² in 50-day-diabetic rats. The average total length of capillaries per glomerulus increased from 12.5±2.2 mm in the control rats to 16.9±2.4 mm in the 10-day-diabetic rats whereas the further increase to 19.4±3.0 mm in the 50-day-diabetic rats failed to reach statistical significance. The average number of topologically defined capillaries per glomerulus increased from 215±29 in the control rats to 260±45 and 316±29 in the 10-day-diabetic and 50-day-diabetic rats, respectively. The results showed just a slight increase in the mean length of a capillary from 58.1±6.2 m in the control rats to 65.6±2.6 m in the 10-day-diabetic rats after which it normalized in the 50-day-diabetic rats to 61.3±3.6 m. The geometric factor or resistance in Poiseuille's law did not differ between the three groups, neither did the diameter of the capillaries, nor the number of glomeruli. The implications of the formation of capillaries in renal glomeruli are discussed and it is concluded that glomerular capillaries in experimental diabetes grow mainly by the formation of new capillaries.     

Effects of maternal subtotal nephrectomy on the development of the fetal kidney: A morphometric study

The present study was designed to explore if maternal subtotal (5/6) nephrectomy affects the development of fetal rat kidneys using morphometric methods and examining whether there are any apoptotic changes in the fetal kidney. To generate 5/6 nephrectomized model rats, animals underwent 2/3 left nephrectomy on gestation day (GD) 5 and total right nephrectomy on GD 12. The fetal kidneys were examined on GDs 16 and 22. A significant decrease in fetal body weight resulting from maternal 5/6 nephrectomy was observed on GD 16, and a significant decrease in fetal renal weight and fetal body weight caused by maternal nephrectomy was observed on GD 22. Maternal 5/6 nephrectomy induced a significant increase in glomerular number, proximal tubular length, and total proximal tubular volume of fetuses on GD 22. Maternal 5/6 nephrectomy resulted in an increase in the number of apoptotic cells in the metanephric mesenchyme of the kidney on GD 16, and in the collecting tubules on GD 22. These findings suggest that maternal 5/6 nephrectomy stimulates the development of the fetal kidney while suppressing fetal growth.     

Renal Mechanisms of Association between Fibroblast Growth Factor 1 and Blood Pressure

The fibroblast growth factor 1 (FGF1) gene is expressed primarily in the kidney and may contribute to hypertension. However, the biologic mechanisms underlying the association between FGF1 and BP regulation remain unknown. We report that the major allele of FGF1 single nucleotide polymorphism rs152524 was associated in a dose-dependent manner with systolic BP (P=9.65×10⁻⁵) and diastolic BP (P=7.61×10⁻³) in a meta-analysis of 14,364 individuals and with renal expression of FGF1 mRNA in 126 human kidneys (P=9.0×10⁻³). Next-generation RNA sequencing revealed that upregulated renal expression of FGF1 or of each of the three FGF1 mRNA isoforms individually was associated with higher BP. FGF1-stratified coexpression analysis in two separate collections of human kidneys identified 126 FGF1 partner mRNAs, of which 71 and 63 showed at least nominal association with systolic and diastolic BP, respectively. Of those mRNAs, seven mRNAs in five genes (MME, PTPRO, REN, SLC12A3, and WNK1) had strong prior annotation to BP or hypertension. MME, which encodes an enzyme that degrades circulating natriuretic peptides, showed the strongest differential coexpression with FGF1 between hypertensive and normotensive kidneys. Furthermore, higher level of renal FGF1 expression was associated with lower circulating levels of atrial and brain natriuretic peptides. These findings indicate that FGF1 expression in the kidney is at least under partial genetic control and that renal expression of several FGF1 partner genes involved in the natriuretic peptide catabolism pathway, renin-angiotensin cascade, and sodium handling network may explain the association between FGF1 and BP.     

TGF-β1对鼠肾小球白蛋白通透性的影响

[目的]探讨转化生长因子-β1(TGF-β1)对大鼠离体肾小球白蛋白通透性的影响及可能的作用机制.[方法]正常雄性SD大鼠,用标准筛技术游离肾小球,应用电视显微术通过肾小球体积变化计算肾小球白蛋白的通透性(Palb).大鼠离体肾小球分别与不同浓度(1 ng/ml、2.5 ng/ml、5 ng/ml、10 ng/ml)TGF-β1孵育30 min;与10 ng/ml TGF-β1孵育不同时间(15 min、30 min、45 min、60 min);与5 ng/ml、10 ng/ml TGF-β1及超氧化物歧化酶(SOD)孵育60 min;在没有TGF-β1下与SOD一起孵育60 min,观察不同情况下Palb.[结果]大鼠离体肾小球与1或2.5 ng/ml TGF-β1孵育30 min对Palb无明显影响,与5或10 ng/ml TGF-β1孵育导致Palb显著增加(P＜0.01),且10 ng/ml TGF-β1对Palb影响更为显著;与10 ng/mlTGF-β1一起孵育15、30、45、60 min,Palb均较对照组明显增加(P＜0.01),且随时间延长Palb逐渐增加,孵育60 min时Palb最大;与5 ng/ml、10 ng/mlTGF-β1及SOD一起孵育60 min,Palb无明显增加;与SOD一起孵育Palb亦无明显增加.[结论]TGF-β1呈剂量时间依赖性增加鼠肾小球Palb,TGF-β1可能通过活性氧簇(ROS)介导P出增加,导致蛋白尿;而SOD可减少白蛋白排泄而有肾保护作用.     

关于海马内突触小球超微结构的辨认

用电镜技术对大白鼠海马ＣＡｌ区的突触小球超微结构作了观察，发现有二种形态的突触小球。一种是小球的突触神经成分均封闭在球内，另一种是小球内的苔状纤维终末与球外神经毯内的树突于形成轴－树突触。小球的中央轴突终末即是苔状纤维终末，它不仅与树突侧棘形成轴－棘突触，而且与树突形成轴－树突触。树－树突触在小球内亦可见到。本文就突触小球的结构成分和突触小球的概念等问题进行了讨论。     

Expression Profile of Human Renal Mesangial Cells Is Altered by Infection with Pathogenic Puumala Orthohantavirus

Acute kidney injury (AKI) with proteinuria is a hallmark of infections with Eurasian orthohantaviruses. Different kidney cells are identified as target cells of hantaviruses. Mesangial cells may play a central role in the pathogenesis of AKI by regulation of inflammatory mediators and signaling cascades. Therefore, we examined the characteristics of hantavirus infection on human renal mesangial cells (HRMCs). Receptor expression and infection with pathogenic Puumala virus (PUUV) and low-pathogenic Tula virus (TULV) were explored. To analyze changes in protein expression in infected mesangial cells, we performed a proteome profiler assay analyzing 38 markers of kidney damage. We compared the proteome profile of in vitro-infected HRMCs with the profile detected in urine samples of 11 patients with acute hantavirus infection. We observed effective productive infection of HRMCs with pathogenic PUUV, but only poor abortive infection for low-pathogenic TULV. PUUV infection resulted in the deregulation of proteases, adhesion proteins, and cytokines associated with renal damage. The urinary proteome profile of hantavirus patients demonstrated also massive changes, which in part correspond to the alterations observed in the in vitro infection of HRMCs. The direct infection of mesangial cells may induce a local environment of signal mediators that contributes to AKI in hantavirus infection.     

小鼠肾脏肾小体发育中的细胞凋亡

目的 研究小鼠肾脏肾小体发育中的细胞凋亡，方法 不同胚龄和出生后小鼠肾脏做常规光镜标本，然后进行TUNE染色，结果 在胚龄14天肾小体发生时就出现细胞凋亡，以后细胞凋亡指数迅速增高，在胚断18天左右达到高峰，随后缓慢下降。结论 小鼠肾脏肾小体发育的整个发育过程均存在细胞凋亡现象。细胞凋亡高峰在胚龄18天左右。