Neuronal prostaglandin E2 receptor subtype EP3 mediates antinociception during inflammation.

The pain mediator prostaglandin E2 (PGE2) sensitizes nociceptive pathways through EP2 and EP4 receptors, which are coupled to Gs proteins and increase cAMP. However, PGE2 also activates EP3 receptors, and the major signaling pathway of the EP3 receptor splice variants uses inhibition of cAMP synthesis via Gi proteins. This opposite effect raises the intriguing question of whether the Gi-protein-coupled EP3 receptor may counteract the EP2 and EP4 receptor-mediated pronociceptive effects of PGE2.

Tailoring and histochemical application of fluorescent homo-dimeric styryl dyes using frozen sections: from peroxidase substrates to new cytochemical probes for mast cells, keratin, cartilage and nucleic acids.

Homo-dimers of styryl dyes were chemically tailored in order to become specific cytochemical probes for use in the life sciences. Histochemical applications using fixed cryotome sections are discussed. It is concluded, that homo-dimerization of specific styryl substrates of peroxidase (PO) by way of their covalent linkage, does not necessarily lead to improved detection sensitivity of endogenous and immuno-bound peroxidase (PO) activity.

Effects of prostaglandin D2 on tetrodotoxin-resistant Na+ currents in DRG neurons of adult rat.

Tetrodotoxin-resistant (TTX-R) Na(+) channels play a key role in the generation of action potentials in nociceptive dorsal root ganglion (DRG) neurons and are an important target for the proinflammatory mediator prostaglandin E(2), which augments these currents. Prostaglandin D(2) (PGD(2)) is released in the tissue together with prostaglandin E(2), and it was reported to be antiinflammatory, but its effect on primary afferent neurons is unclear. In the present study we localised G(s)-protein-coupled DP1 and G(i)-protein-coupled DP2 receptors in DRG neurons, and we assessed the effect of PGD(2) on TTX-R Na(+) currents in patch-clamp recordings from small- to medium-sized cultured DRG neurons from adult rats.

Detection of endogenous and immuno-bound peroxidase--the status quo in histochemistry.

The discovery of synthetic dyes goes back to 1856 and launched the development of the whole chemical and pharmaceutical industry. In life sciences synthetic dyes represent indispensable tools for the microscopic and macroscopic level. Small dyes have the advantage of their easy adaptability to various measuring equipments.

Two-photon microscopy of deep intravital tissues and its merits in clinical research.

Multiphoton excitation laser scanning microscopy, relying on the simultaneous absorption of two or more photons by a molecule, is one of the most exciting recent developments in biomedical imaging. Thanks to its superior imaging capability of deeper tissue penetration and efficient light detection, this system becomes more and more an inspiring tool for intravital bulk tissue imaging. Two-photon excitation microscopy including 2-photon fluorescence and second harmonic generated signal microscopy is the most common multiphoton microscopic application.