Role of cAMP and Neutrophil Cyclooxygenase in Gonadotropin-Dependent Regulation of T Lymphocyte Proliferation

S. V. Shirshev and E. M. Kuklina^*

Institute of Ecology and Genetics, Ural Branch of the Russian Academy of Sciences, ul. Goleva 13, Perm', 614081 Russia; fax: (3422) 646-711; E-mail: conf@ecology.psu.ru

^* To whom correspondence should be addressed.

Received February 2, 2001; Revision received March 21, 2001

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The effect of the main pregnancy hormone, chorionic gonadotropin (CG), on proliferation of peripheral blood mononuclear cells (PBMC) was studied in the presence of autologous neutrophils; also, hormone-dependent regulation of the cAMP levels in T lymphocytes and neutrophils was evaluated. PBMC proliferation in response to a mitogen is suppressed by physiological doses of CG (10, 50, and 100 IU/ml). Autologous neutrophils enhance the suppression induced by the low dose of CG (10 IU/ml), but when cyclooxygenase was inhibited this effect was not observed; this suggests that the anti-proliferative effects of the low dose of CG can be mediated by the products generated by neutrophil cyclooxygenase. The effect of CG was associated with increased cAMP levels in T lymphocytes and neutrophils. Comparison of functional and cAMP-related effects of CG in both cell populations indicates that cAMP is involved in the anti-proliferative effects of CG.

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KEY WORDS: chorionic gonadotropin, T lymphocytes, neutrophils, proliferation, cAMP, cyclooxygenase

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