Format

Send to

Choose Destination
J Clin Invest. 1991 May;87(5):1537-40.

Acute effects of tumor necrosis factor on the microcirculation in rat cremaster muscle.

Author information

1
Laboratoire de Biophysique, Hopital F. Widal, Paris, France.

Abstract

The acute effects of TNF on the microcirculation were studied by in vivo microscopy in rat cremaster muscle. The changes in arteriolar diameter after topical administration of recombinant TNF (rTNF; 10(-4)-10(4) ng/ml) were studied in second-, third-, and fourth-order arterioles (A2-A4) whose mean diameters under control conditions were 64.3, 30.7, and 14.8 microns respectively. rTNF induced a concentration-dependent vasodilation whose amplitude was largest for the smallest arterioles. At the highest concentration tested, arteriolar diameter increased by 21, 29, and 41% of control diameter for the A2, A3, and A4 arterioles, respectively. Indomethacin or mefenamic acid, two structurally different prostaglandin synthesis inhibitors, markedly inhibited the degree of vasodilation induced by rTNF in the three arteriolar orders. As regards the effect of rTNF on vasoconstriction in response to norepinephrine, vasoconstriction was greatest for the smallest arterioles, and did not change 10 min after rTNF administration for any of the three arteriolar orders. We conclude that (a) rTNF has a direct vasodilatory effect which is greatest in the smallest arterioles, (b) this vasodilation is at least partly mediated by prostaglandins, and (c) administration of rTNF in itself does not acutely alter the response of the arterioles to vasopressive drugs.

PMID:
2022725
PMCID:
PMC295234
DOI:
10.1172/JCI115165
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for American Society for Clinical Investigation Icon for PubMed Central
Loading ...
Support Center