Cytokine-mediated regulation of rat ovarian function: interleukin-1 stimulates the accumulation of a 92-kilodalton gelatinase

It is known that the mammalian ovary possesses a complete interleukin-1 (IL-1) system replete with ligands, receptors, and a receptor antagonist. To further assess the hypothesis that IL-1 may play an intermediary role in gonadotropin-triggered ovulation, we have set out to determine whether IL-1 is capable of promoting ovarian collagenase biosynthesis, an established component of the ovulatory cascade. Untreated cultured whole ovarian dispersates from immature (25 day old) rats constitutively elaborated several collagenolytic species as assessed in a gelatin matrix. A major 72 kilodalton (kDa) gelatinase (GL) was particularly apparent. Treatment with IL-1 beta produced selective dose- and cell density-dependent increments in the accumulation of a 92-kDa GL species. Administration of an IL-1 receptor antagonist neutralized the IL-1-induced stimulation of the 92-kDa GL in a dose-dependent fashion thereby supporting the presumption that the IL-1 effect is receptor mediated. Studies of comparable cellular de...