Testicular toxicity in mice exposed to terephthalic acid in utero and during lactation.

Terephthalic acid (TPA) is a worldwide aromatic compound widely used to manufacture resins and the raw material for the polymerization reaction with ethylene glycol to produce polyethylene terephthalate, known as PET. The use of TPA extends to the synthesis of phthalates, plasticizers used in various industrialized products such as toys and cosmetics. The present study aimed to evaluate the testicular toxicity of terephthalic acid on male mice exposed in utero and during lactation to TPA in different developmental windows.

Effects of 3-Heptyl-3,4,6-trimethoxy-3H-isobenzofuran-1-one alone or/in association with cyclophosphamide on testicular function.

Chemotherapy for cancer treatment may result in a temporary or long-term gonadal damage resulting in subfertility or infertility. Cyclophosphamide (CY) is a cytotoxic alkylating agent that has been widely used in the treatment of cancer. Recent studies have shown that synthetic resorcinol lipid AMS35AA (3-Heptyl-3,4,6-trimethoxy-3H-isobenzofuran-1-one) may be an important adjuvant chemotherapy that potentiates mutagenic damage and increases apoptosis caused by CY.

Membrane cholesterol regulates different modes of synaptic vesicle release and retrieval at the frog neuromuscular junction.

We investigated the effects of cholesterol removal on spontaneous and KCl-evoked synaptic vesicle recycling at the frog neuromuscular junction. Cholesterol removal by methyl-β-cyclodextrin (MβCD) induced an increase in the frequency of miniature end-plate potentials (MEPPs) and spontaneous destaining of synaptic vesicles labeled with the styryl dye FM1-43. Treatment with MβCD also increased the size of MEPPs without causing significant changes in nicotinic receptor clustering.

Using the fluorescent styryl dye FM1-43 to visualize synaptic vesicles exocytosis and endocytosis in motor nerve terminals.

The styryl dye FM1-43 is a powerful tool to track exocytosis, endocytosis and recycling of secretory granules or vesicles. Due to its unique structure, dye molecules reversibly partition into the outer leaflet of surface membrane without permeating due to two cationic charges located in their headgroup. When a secretory cell is stimulated to evoke exocytosis, FM1-43 molecules that were inserted in the membrane are internalized during compensatory endocytosis and newly formed secretory granules or vesicles become stained with dye (staining/endocytosis).

The vesicular acetylcholine transporter is required for neuromuscular development and function.

The vesicular acetylcholine (ACh) transporter (VAChT) mediates ACh storage by synaptic vesicles. However, the VAChT-independent release of ACh is believed to be important during development. Here we generated VAChT knockout mice and tested the physiological relevance of the VAChT-independent release of ACh.

Ouabain evokes exocytosis dependent on ryanodine and mitochondrial calcium stores that is not followed by compensatory endocytosis at the neuromuscular junction.

Ouabain is a cardiotonic glycoside that inhibits the sodium potassium ATPase pump leading to sodium accumulation in nerve terminals. At the frog neuromuscular junction, ouabain induces acetylcholine release and a rapid depletion of synaptic vesicles. In the present work, we used FM1-43 vital labeling to dissect the effect of ouabain on synaptic vesicles recycling.

Mice deficient for the vesicular acetylcholine transporter are myasthenic and have deficits in object and social recognition.

An important step for cholinergic transmission involves the vesicular storage of acetylcholine (ACh), a process mediated by the vesicular acetylcholine transporter (VAChT). In order to understand the physiological roles of the VAChT, we developed a genetically altered strain of mice with reduced expression of this transporter. Heterozygous and homozygous VAChT knockdown mice have a 45% and 65% decrease in VAChT protein expression, respectively.