The sciatic nerve normally leaves the pelvis by passing through the greater sciatic foramen below piriformis. However, it may divide into its common fibular and tibial nerve components within the pelvis and its relationship with piriformis is variable. In this paper, we describe a new anatomical variation in which the common fibular nerve passed superior, and the tibial nerve inferior, to the superior gemellus muscle. Anatomical variations such as these may contribute to piriformis syndrome, coccygodynia and muscle atrophy.

Erectile dysfunction is a common side effect of finasteride and dutasteride treatments. The objective of this study was to investigate the structural changes in the penis using a benign prostatic hyperplasia (BPH) rodent model treated with dutasteride or finasteride. Sixty male rats were divided into the following groups: C, untreated control rats; C + D, control rats receiving dutasteride; C + F, control rats receiving finasteride; H, untreated spontaneously hypertensive rats (SHRs); H + D, SHRs treated with dutasteride; and H + F, SHRs treated with finasteride. Treatments were performed for 40 days, and penises were collected immediately thereafter. The organs were analyzed using histomorphometric methods to determine the cross-sectional penile area, as well as the surface density (Sv) of smooth muscle fibers, connective tissue, elastic system fibers, and sinusoidal spaces of the corpus cavernosum. The results were compared using a one-way ANOVA with Bonferroni's posttest. Groups C + D and C + F had a significantly smaller penile cross-sectional area, but more elastic system fiber Sv compared to Group C. Group C + D showed less smooth muscle Sv, and Group H showed more connective tissue but a smaller sinusoidal space Sv in the corpus cavernosum compared to Group C. Groups H + D and H + F had less smooth muscle Sv than Group H. Group H + D also had more connective tissue and elastic system fiber Sv than Group H. Both dutasteride and finasteride promoted penile modifications in the control rat penis, although this affect was greater in Group H animals. In this rodent model, dutasteride was the drug that most affected the corpus cavernosum.

The objective of this study was to investigate the effects of chronic stress on the testes of prepubertal and adult rats and to evaluate whether any alterations could be reversed when stress induction is ended. Seventy-six male rats were assigned to eight groups depending on the type of treatment (control or stressed), the age at which stress was initiated (prepubertal or adult), and the time of evaluation (immediate or late). Stress stimuli were applied for 6 weeks. Stressed prepubertal and adult rats evaluated immediately after the last stress stimulus were included in SP-I and SA-I groups, respectively. The late prepubertal (SP-L) and adult (SA-L) groups of stressed rats were evaluated 6 weeks after the last stress stimulus. Age-matched rats were used as controls (CP-I, CA-I, CP-L, and CA-L groups). Application of stress stimuli to rats in the SP-I group resulted in body weight and seminiferous tubule diameter reduction. The rats in the SA-I group also showed several functional (testosterone level and sperm parameter) and morphological (testicular weight and seminiferous tubule diameter) reductions. The rats in the SP-L group showed increased body weight and intertubular compartment volumetric and absolute densities and reduced tubular compartment volumetric density. The rats in the SA-L group presented only reduced sperm viability. Stress stimuli promoted changes in the rats in all the study groups. The testes of the adult rats were the most affected by chronic stress. However, the stressed adult rats recovered well from the testicular alterations.

20Animal behaviors are robust and flexible. To elucidate how these two conflicting 21 features of behavior are encoded in the nervous system, we analyzed the neural circuits 22 generating a C. elegans thermotaxis behavior, in which animals migrate toward the past 23 cultivation temperature (T c ). We identified multiple circuits that are highly overlapping 24 but individually regulate distinct behavioral components to achieve thermotaxis. When 25 the regulation of a behavioral component is disrupted following single cell ablations, the 26 other components compensate the deficit, enabling the animals to robustly migrate 27 toward the T c . Depending on whether the environmental temperature surrounding the 28 animals is above or below the T c , different circuits regulate the same behavioral 29 components, mediating the flexible switch between migration up or down toward the T c . 30These context-dependencies within the overlapping sub-circuits reveal the 31 implementation of degeneracy in the nervous system, providing a circuit-level basis for 32 the robustness and flexibility of behavior. 105C. elegans animals are known to navigate using a series of stereotyped movements, 106 designated behavioral components (Croll, 1975; Iino and Yoshida, 2009; 107 Pierce- Shimomura et al., 1999). We first attempted to extract the behavioral components 108 during thermotaxis by employing a Multi-Worm Tracker (MWT) (Swierczek et al., 109 2011). MWT simultaneously captured the positions and postures of approximately 120 110 animals ( Figure 1A), and these data were further analyzed by a custom-built MATLAB 111 script to detect the behavioral components (see Materials and methods). 112For the thermotaxis assays, we set cultivation temperature (T c ) as 20°C and the 113 temperature of the center in the assay plate as either 17°C or 23°C ( Figure 1B). Animals 114 were placed at the center of the plate, and then we evaluated the animals' migrations by 115 calculating thermotaxis index (TTX index), according to the equation shown in Figure 116 1C. TTX index is 1 when all the animals are in the coldest fraction of the plate and 8 117 when all the animals are in the warmest fraction. Consistent with our previous report 118 (Ito et al., 2006), the animals reached their T c within approximately 30 minutes in two 119 conditions ( Figure 1D and Movie S1), plate centered at 17°C or 23°C. In this study, we 120 thus focused on the first 30 minutes from the start of the assays. To analyze the 121 behaviors during the migrations toward the T c , we analyzed the animals that were 122 distributed in the center four fractions of the assay plate; 15.5-18.5°C for the TT c condition (Figure 2A). Behaviors were 124 essentially classified into three behavioral components: turns, reversals, and curves 125 ( Figure 2B). Turns were further classified into omega turns and shallow turns (Kim et 126 al., 2011; Schild and Glauser, 2013), and reversals were further classified into reversals 127 and reve...

13 Genetically encoded voltage indicators (GEVIs) based on microbial rhodopsins utilize the voltage-sensitive 14 fluorescence of the all-trans retinal (ATR) cofactor, while in electrochromic (eFRET) sensors, donor 15 fluorescence drops when the rhodopsin acts as depolarization-sensitive acceptor. We systematically 16 assessed Arch(D95N), Archon, and QuasAr, as well as the eFRET sensors MacQ-mCitrine and QuasAr-17 mOrange, in C. elegans. ATR-bearing rhodopsins reported on voltage changes in body wall muscles (BWMs) 18 and the pharynx, the feeding organ, where Arch(D95N) showed ca. 125 % F/F increase per 100 mV. The ATR 19 fluorescence is very dim, however, using the retinal analog dimethylaminoretinal (DMAR), it was boosted 20 250-fold. eFRET sensors provided sensitivities of 45 % to 78 % F/F per 100 mV, induced by BWM action 21 potentials (APs). All sensors reported differences in muscle depolarization induced by a voltage-gated Ca 2+ -22 channel mutant. Optogenetically evoked de-or hyperpolarization of motor neurons increased or eliminated 23 AP activity and caused a rise or drop in BWM sensor fluorescence. Last, we could analyze voltage dynamics 24 across the entire pharynx, showing uniform depolarization but compartmentalized repolarization of anterior 25 and posterior parts. Our work establishes all-optical, non-invasive electrophysiology in intact C. elegans. 26