PROSTAGLANDIN-F2-ALPHA AND GONADOTROPIN-RELEASING-HORMONE INCREASE INTRACELLULAR FREE CALCIUM IN RAT GRANULOSA-CELLS

MOLECULAR AND CELLULAR ENDOCRINOLOGY

卷:84

Article

RODWAY, MR ; STEELE, GL ; BAIMBRIDGE, KG ; LEUNG, PCK

关键词: PROSTAGLANDIN-F2-ALPHA;    GONADOTROPIN-RELEASING HORMONE;    GRANULOSA CELL;    CALCIUM;   

DOI  :  10.1016/0303-7207(92)90080-P

来源: Elsevier

【 摘 要 】

Changes in cytosolic free calcium concentration ([Ca2+]i) in response to prostaglandin F2-alpha (PGF2-alpha) and gonadotropin-releasing hormone (GnRH) were measured in single rat granulosa cells, using the calcium-sensitive fluorescent dye, fura-2AM. In 90 out of 135 granulosa cells (67%), there was a 3- to 4-fold increase in resting [Ca2+]i within 30 s of administration of PGF2-alpha (10(-6) M). The resting [Ca2+]i returned to pre-stimulation levels in approximately 80 s. Granulosa cells were responsive to PGF2-alpha at concentrations ranging from 10(-7) M to 10(-4) M (n = 7). Within this range of concentrations, the magnitude of the calcium response did not differ. In another series of experiments, the majority (93%, n = 57) of the granulosa cells which responded to PGF2-alpha also responded to GnRH. Neither the magnitude of the [Ca2+]i response nor the time to response differed between PGF2-alpha and GnRH. Furthermore, simultaneous treatment of granulosa cells with both hormones did not generate a larger response than with either hormone alone. During perifusion with low calcium media, the characteristic [Ca2+]i response to PGF2-alpha decreased, and was eliminated within 10 min (n = 9). Similar observations were made in response to GnRH under these conditions. These data confirm that PGF2-alpha and GnRH stimulate a transient increase in [Ca2+]i in rat granulosa cells, the source of which may be shared intracellular stores.

【 授权许可】

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