Search PubMed⌕ Search

Biomedical subjects

J Sundelin

Publications and source records attributed to J Sundelin.

41 records · Page 3Linked to original sources

Isolation and identification of a cDNA clone coding for an HLA-DR transplantation antigen alpha-chain.

Membrane-bound mRNA was isolated from Raji cells and enriched for message coding for the HLA-DR transplantation antigen alpha-chain by sucrose gradient centrifugation. Double-stranded cDNA was constructed from this mRNA fraction, ligated to plasmid pBR322, and cloned into Escherichia coli. By hybrid selection, a plasmid, pDR-alpha-1, able to hybridize with mRNA coding for the HLA-DR alpha-chain was identified. From the nucleotide sequence of one end of the insert an amino acid sequence was predicted which is identical to part of the amino-terminal sequence of an HLA-DR alpha-chain preparation isolated from Raji cells. This clearly shows that pDR-alpha-1 carries almost the complete message for an HLD-DR alpha-chain. From the nucleotide sequence of this plasmid it will be possible to predict the primary structure of an HLA-DR alpha-chain.

Amino Acid Sequence↗

Vascular effects of proteinase-activated receptor 2 agonist peptide.

Proteinase-activated receptor 2 (PAR-2) is a G protein-coupled receptor related to the thrombin receptor. PAR-2 can be activated by trypsin and by synthetic peptides corresponding to the new amino terminus generated by activating proteolytic cleavage. We show in this report that intravenous injection of PAR-2 agonist peptides has dramatic effects on arterial blood pressure in anesthetized rats. The peptide SLIGRLETQPPI, at 150 nmol/kg, transiently decreased the mean arterial pressure from 104 to 60 mm Hg. The hypotensive response was dose-dependent, and was not secondary to effects on central vasoregulatory systems, heart rate, or the kidneys. A nitric oxide synthase inhibitor attenuated the hypotensive response induced by the PAR-2 agonist peptide. Further experiments in vitro, on preparations of rat femoral artery and vein, showed that PAR-2 agonist peptide elicited a dose-dependent relaxation of both types of vessel. Removal of the endothelium abolished the agonist peptide-induced relaxation. Our results demonstrate that activation of PAR-2 can modulate vascular tone, and that this response was an effect mediated at least partly by nitric oxide. The effect on blood vessels further suggests that the physiological activator of this proteolytically activated receptor is an enzyme present and active in the blood, possibly after a vascular injury.

Amino Acid Sequence↗