The estrogen antagonist tamoxifen inhibits carrageenan induced inflammation in LEW/N female rats.
Carrageenan induces a measurable inflammatory response in susceptible animals, and mature females are more responsive to carrageenan, than males. In the present study, we tested whether the estrogen antagonist tamoxifen influences carrageenan-induced inflammatory responses. Female LEW/N rats were treated with tamoxifen and compared to a control group of animals injected with vehicle. Tamoxifen significantly reduced estrous phase of estrous cycle during treatment, consistent with its functional anti-estrogen effects. Moreover, tamoxifen significantly decreased exudate volume but did not significantly influence relative white blood cell counts in the exudate. Interestingly, tamoxifen induced differential dose-dependent alterations in peripheral blood lymphocyte subpopulations. Low dose of tamoxifen increased CD25 cells. The high tamoxifen dose significantly increased CD8 blood lymphocytes counts. Our data indicate that tamoxifen treatment decreases carrageenan-induced inflammatory response in female LEW/N rats and suggest therefore that this inflammatory response is, at least in part, estrogen related. Moreover, our results suggest a possible role for tamoxifen in treatment of inflammatory disorders.
Misiewicz
B
B
Clinical Neuroendocrinology Branch, National Institute of Mental Health, Bethesda, MD 20892, USA.
Griebler
C
C
Gomez
M
M
Raybourne
R
R
Zelazowska
E
E
Gold
P W
PW
Sternberg
E M
EM
D000818:Animals; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000627:therapeutic use*; D018414:CD8-Positive T-Lymphocytes / Q000187:drug effects; D002351:Carrageenan / Q000037:antagonists & inhibitors*; D004347:Drug Interactions; D004965:Estrogen Antagonists / Q000627:therapeutic use*; D004971:Estrus / Q000187:drug effects; D005260:Female; D007249:Inflammation / Q000097:blood / Q000139:chemically induced / Q000517:prevention & control*; D016131:Lymphocyte Subsets / Q000187:drug effects; D008214:Lymphocytes / Q000187:drug effects; D051381:Rats; D011917:Rats, Inbred Lew; D015375:Receptors, Interleukin-2 / Q000032:analysis; D013629:Tamoxifen / Q000627:therapeutic use*
D000894:Anti-Inflammatory Agents, Non-Steroidal; D004965:Estrogen Antagonists; D015375:Receptors, Interleukin-2; D013629:Tamoxifen; D002351:Carrageenan