Generation of a ChAT mouse line without the early onset hearing loss typical of the C57BL/6J strain.

The development of knockin mice with Cre recombinase expressed under the control of the promoter for choline acetyltransferase (ChAT) has allowed experimental manipulation of cholinergic circuits. However, currently available ChAT mouse lines are on the C57BL/6J strain background, which shows early onset age-related hearing loss attributed to the Cdh23 mutation (a.k.

Ultrastructural characterization of GABAergic and excitatory synapses in the inferior colliculus.

In the inferior colliculus (IC) cells integrate inhibitory input from the brainstem and excitatory input from both the brainstem and auditory cortex. In order to understand how these inputs are integrated by IC cells identification of their synaptic arrangements is required. We used electron microscopy to characterize GABAergic synapses in the dorsal cortex, central nucleus, and lateral cortex of the IC (ICd, ICc, and IClc) of guinea pigs.

Auditory cortical axons contact commissural cells throughout the guinea pig inferior colliculus.

Projections from auditory cortex (AC) affect how cells in both inferior colliculi (IC) respond to acoustic stimuli. The large projection from the AC to the ipsilateral IC is usually credited with the effects in the ipsilateral IC. The circuitry underlying effects in the contralateral IC is less clear.

Ultrastructural examination of the corticocollicular pathway in the guinea pig: a study using electron microscopy, neural tracers, and GABA immunocytochemistry.

Projections from auditory cortex (AC) can alter the responses of cells in the inferior colliculus (IC) to sounds. Most IC cells show excitation and inhibition after stimulation of the AC. AC axons release glutamate and excite their targets, so inhibition is presumed to result from cortical activation of GABAergic IC cells that inhibit other IC cells via local projections.

Analysis of excitatory synapses in the guinea pig inferior colliculus: a study using electron microscopy and GABA immunocytochemistry.

The inferior colliculus (IC) integrates ascending auditory input from the lower brainstem and descending input from the auditory cortex. Understanding how IC cells integrate these inputs requires identification of their synaptic arrangements. We describe excitatory synapses in the dorsal cortex, central nucleus, and lateral cortex of the IC (ICd, ICc and IClc) in guinea pigs.

Distribution of cholinergic cells in guinea pig brainstem.

We used an antibody to choline acetyltransferase (ChAT) to label cholinergic cells in guinea pig brainstem. ChAT-immunoreactive (IR) cells comprise several prominent groups, including the pedunculopontine tegmental nucleus, laterodorsal tegmental nucleus, and parabigeminal nucleus, as well as the cranial nerve somatic motor and parasympathetic nuclei. Additional concentrations are present in the parabrachial nuclei and superior colliculus.

Synergistic antitumour activity of vitamins C and K3 against human prostate carcinoma cell lines.

Vitamins C, K3 (VC, VK3) and a VC/VK3 combination with a VC:VK3 ratio of 100:1 were assayed for their antitumour activity against two human prostatic carcinoma cell lines. Co-administration of the vitamins enhanced the antitumour activity 5- to 20-fold even with a 1 h exposure time. While exogenous catalase destroyed the antitumour activity, hydrogen peroxide-induced lipid peroxidation was negligible.

Flow cytometric and ultrastructural aspects of the synergistic antitumor activity of vitamin C-vitamin K3 combinations against human prostatic carcinoma cells.

Transmission and scanning electron microscopy and flow cytometry were employed to characterize the cytotoxic effects of vitamin C (VC), vitamin K3 (VK3), or VC-VK3 combinations on a human prostate carcinoma cell line (DU145) following a 1-h vitamin treatment and a 24-h incubation in culture medium. Cells exposed to VC exhibited membranous blebs, aberrant microvillar morphology, mitochondria with swollen cristae and intramitochondrial deposits, as well as nucleoli with segregated components. VK3-treated cells displayed a damaged cytoskeleton and membranes, a cytoplasm which contained large lumen, condensed polysomes, and severely damaged mitochondria with residual bodies, and nuclei which exhibited chromatic condensation, pyknosis, and karyolysis.

Synergistic antitumor activity of vitamins C and K3 on human urologic tumor cell lines.

A micro-tetrazolium assay was employed to evaluate vitamin C (VC), vitamin K3 (VK3) and vitamin C/vitamin K3 combinations (VC/VK3) for their antitumor activity against eight human urologic tumor cell lines. While the individual vitamins exhibited antitumor activity at high concentrations, co-administration of the vitamins in a VC : VK3 ratio of 100 : 1 potentiated antitumor activity 4- to 61-fold even when exposure times were as short as 1 hour. Administration of exogenous catalase destroyed the antitumor activity of the vitamins and suggested that hydrogen peroxide and perhaps other reactive oxygen species were involved in the antitumor mechanism of these vitamins.