Learn More
Extracellular ATP has multimodal actions in the cochlea affecting hearing sensitivity. ATP-gated ion channels involved in this process were characterized in the guinea pig cochlea. Voltage-clamped hair cells exhibited a P2 receptor pharmacology compatible with the assembly of ATP-gated ion channels from P2X(2) receptor subunits. Reverse transcription-PCR(More)
Reissner's membrane forms a partition between the endolymphatic and perilymphatic cochlear compartments. Expression of the P2X2 receptor subunit which assembles to form ATP-gated ion channels was detected in guinea-pig Reissner's membrane using the reverse transcription polymerase chain reaction (RT-PCR). The P2X2 receptor subunit protein was localized to(More)
In the cochlea, extracellular ATP influences the endocochlear potential, micromechanics, and neurotransmission via P2 receptors. Evidence for this arises from studies demonstrating widespread expression of ATP-gated ion channels (assembled from P2X receptor subunits) and G protein-coupled receptors (P2Y receptors). P2X2 receptor subunits are localized to(More)
The large-scale extraction and partial purification of endogenous 3',5'-cyclic UMP, 3',5'-cyclic IMP and 3',5'-cyclic dTMP are described. Rat liver, kidney, heart, spleen and lung tissues were subjected to a sequential purification procedure involving freeze-clamping, perchlorate extraction, alumina and Sephadex ion-exchange chromatography and preparative(More)
Male reproduction is dependent upon seminal emission mediated by vas deferens contraction. This drives spermatic fluid to the prostatic urethra during ejaculation. We localize interstitial cells of Cajal (ICC), which express P2X2 receptor, subunits of ATP-gated ion channels, to rat, mouse and guinea-pig vas deferens submucosa. Reverse(More)
The large-scale extraction and purification to homogeneity of cyclic CMP and its unequivocal identification are described. Rat liver, kidney, heart, spleen and lung tissues were subjected to a sequential purification procedure involving freeze-clamping, perchlorate extraction, alumina and boronate column chromatography, polyacrylamide-gel column(More)
Spiral ganglion neurones in rat cochlea express three different isoforms of the P2X2 receptor subunit which assemble into ATP-gated ion channels. Two of these P2X2R subunit isoforms have previously been detected in other auditory tissues. The third isoform (designated P2X2-3R) has not been described. This isoform lacks 39 bp immediately prior to the stop(More)
Spiral ganglion neurones provide the primary afferent innervation to sensory hair cells within the mammalian cochlea. Recent evidence suggests that their function may be modulated by purinergic signalling mechanisms, associated with release of adenosine 5'-triphosphate (ATP). Utilising a newly developed slice preparation of the neonatal rat cochlea, we have(More)
The use of nanoparticles in medicine is ever increasing, and it is important to understand their targeted and non-targeted effects. We have previously shown that nanoparticles can cause DNA damage to cells cultured below a cellular barrier without crossing this barrier. Here, we show that this indirect DNA damage depends on the thickness of the cellular(More)
Extracellular ATP acts via ionotropic P2X receptors to mediate fast neurotransmission in the central and autonomic nervous systems. Recent data, including identification of P2X2 receptor mRNA expression by spiral ganglion neurones, suggests that purinergic signalling may influence auditory neurotransmission via ATP-gated ion channels assembled from these(More)