PDGFRα subepithelial interstitial cells act as a pacemaker to drive smooth muscle of the guinea pig seminal vesicle.

Smooth muscle cells (SMCs) of the guinea pig seminal vesicle (SV) develop spontaneous phasic contractions, Ca flashes and electrical slow waves in a mucosa-dependent manner, and thus it was envisaged that pacemaker cells reside in the mucosa. Here, we aimed to identify the pacemaker cells in SV mucosa using intracellular microelectrode and fluorescence Ca imaging techniques. Morphological characteristics of the mucosal pacemaker cells were also investigated using focused ion beam/scanning electron microscopy tomography and fluorescence immunohistochemistry.

Role of mucosa in generating spontaneous activity in the guinea pig seminal vesicle.

Key Points: The mucosa may have neuron-like functions as urinary bladder mucosa releases bioactive substances that modulate sensory nerve activity as well as detrusor muscle contractility. However, such mucosal function in other visceral organs remains to be established. The role of mucosa in generating spontaneous contractions in seminal vesicles (SVs), a paired organ in the male reproductive tract, was investigated.

Interstitial cell modulation of pyeloureteric peristalsis in the mouse renal pelvis examined using FIBSEM tomography and calcium indicators.

Typical and atypical smooth muscle cells (TSMCs and ASMCs, respectively) and interstitial cells (ICs) within the pacemaker region of the mouse renal pelvis were examined using focused ion beam scanning electron (FIB SEM) tomography, immunohistochemistry and Ca imaging. Individual cells within 500-900 electron micrograph stacks were volume rendered and associations with their neighbours established. 'Ribbon-shaped', Ano1 Cl channel immuno-reactive ICs were present in the adventitia and the sub-urothelial space adjacent to the TSMC layer.

Correlative light and electron microscopic observation of mitochondrial DNA in mammalian cells by using focused-ion beam scanning electron microscopy.

IntroductionMitochondrial fission and fusion events are fundamental mechanisms for quality control of mitochondrial functions. Mitochondrial DNA (mtDNA) usually divides in offspring mitochondria after fission and mtDNA dynamics are thought to be coordinated with mitochondrial turnover. Recently, several candidate mechanisms for the relationship between mtDNA division and mitochondrial fission have been suggested ([1], 2012).

En bloc staining with hydroquinone treatment for block face imaging.

IntroductionBecause recent three-dimensional (3D) ultrastructural reconstruction techniques such as serial block face scanning electron microscopy (SBFSEM), obtain their images directly from the flat surface of specimens via material contrast[1], specimens should be strongly stained with heavy metals prior to resin embedding in order to obtain higher material contrast using backscattered electrons (BSEs). To enhance membrane contrast for block face imaging (BFI), we usually stain specimens using the method published by Deerinck[2], and the images obtained show TEM-like contrast.However, recently, our research subjects have required reconstruction of a much larger volume, increasing the total image acquisition time.

Functional and morphological properties of pericytes in suburothelial venules of the mouse bladder.

Background And Purpose: In suburothelial venules of rat bladder, pericytes (perivascular cells) develop spontaneous Ca(2+) transients, which may drive the smooth muscle wall to generate spontaneous venular constrictions. We aimed to further explore the morphological and functional characteristics of pericytes in the mouse bladder.

Experimental Approach: The morphological features of pericytes were investigated by electron microscopy and fluorescence immunohistochemistry.

Beam deceleration for block-face scanning electron microscopy of embedded biological tissue.

The beam deceleration (BD) method for scanning electron microscopes (SEM) also referred to as "retarding" was applied to back-scattered electron (BSE) imaging of the flat block face of a resin embedded biological specimen under low accelerating voltage and low beam current conditions. BSE imaging was performed with 0-4 kV of BD on en bloc stained rat hepatocyte. BD drastically enhanced the compositional contrast of the specimen and also improved the resolution at low landing energy levels (1.

Helical arrangement of filaments in microvillar actin bundles.

Actin filament arrays in in vivo microvillar bundles of rat intestinal enterocyte were re-evaluated using electron tomography (ET). Conventional electron microscope observation of semi-thin cross sections (300nm thick) of high-pressure freeze fixed and resin embedded brush border has shown a whirling pattern in the center of the microvilli instead of hexagonally arranged dots, which strongly suggests that the bundle consists of a non-parallel array of filaments. A depth compensation method for the ET was developed to estimate the actual structure of the actin bundle.