Generation of Parabiotic Zebrafish Embryos by Surgical Fusion of Developing Blastulae.

Surgical parabiosis of two animals of different genetic backgrounds creates a unique scenario to study cell-intrinsic versus cell-extrinsic roles for candidate genes of interest, migratory behaviors of cells, and secreted signals in distinct genetic settings. Because parabiotic animals share a common circulation, any blood or blood-borne factor from one animal will be exchanged with its partner and vice versa. Thus, cells and molecular factors derived from one genetic background can be studied in the context of a second genetic background.

Hematopoietic stem cells develop in the absence of endothelial cadherin 5 expression.

Rare endothelial cells in the aorta-gonad-mesonephros (AGM) transition into hematopoietic stem cells (HSCs) during embryonic development. Lineage tracing experiments indicate that HSCs emerge from cadherin 5 (Cdh5; vascular endothelial-cadherin)(+) endothelial precursors, and isolated populations of Cdh5(+) cells from mouse embryos and embryonic stem cells can be differentiated into hematopoietic cells. Cdh5 has also been widely implicated as a marker of AGM-derived hemogenic endothelial cells.

The effects of chronic treatment with the dihydropyridine, Bay K 8644, on hyperexcitability due to ethanol withdrawal, in vivo and in vitro.

1. The effects of chronic treatment with the dihydropyridine, Bay K 8644, were studied on the ethanol withdrawal syndrome, in vivo and in vitro. 2.

The antimigraine drugs ergotamine and dihydroergotamine are potent 5-HT1C receptor agonists in piglet choroid plexus.

1. Fozard & Gray (1989) proposed that migraine is mediated by stimulation of 5-HT1C receptors. We have examined the interaction of two effective anti-migraine agents, ergotamine and dihydroergotamine (DHE), with these receptors.