GONADOTROPIN SURGE-ATTENUATING FACTOR ATTENUATES INVITRO LH-SECRETION INDUCED BY GONADOTROPIN-RELEASING-HORMONE FROM CULTURED OVINE PITUITARY-CELLS ONLY DURING THE BREEDING-SEASON

被引:21
作者
FOWLER, PA [1 ]
TOWNSEND, C [1 ]
MESSINIS, IE [1 ]
CUNNINGHAM, P [1 ]
TEMPLETON, A [1 ]
机构
[1] UNIV IOANNINA,DEPT OBSTET & GYNAECOL,GR-45332 IOANNINA,GREECE
关键词
D O I
10.1677/joe.0.1350221
中图分类号
R5 [内科学];
学科分类号
1002 ; 100201 ;
摘要
Primary cultures of ovine pituitaries from adult ewes were used to investigate aspects of gonadotrophin surge-attenuating factor (GnSAF) bioactivity in human follicular fluid (hFF) from superovulated women. During the autumn and first half of the winter, LH secretion induced by gonadotrophin-releasing hormone (GnRH) was markedly reduced (43-5+/-5.2% of control GnRH-induced LH secretion) by incubation for 48 h with steroid-free hFF. For the rest of the year, treatment with the same batch of steroid-free hFF resulted in non-significant reduction or stimulation of GnRH-induced 1-H secretion (71.3+/-13.2 to 117.8+/-11.2% of control GnRH-induced LH secretion). Incubation of pituitary cells for 48 h with oestradiol (1 pmol/l to 1 mumol/l), progesterone (1 pmol/l to 1 mumol/l) or oestradiol and progesterone combined (1 pmol/l to 1 mumol/l) in a two-way titration for 48 h had no significant effect on GnRH-induced LH secretion (83.4+/-7.6 to 110.6+/-5.0% of control secretion). Separating hFF into fractions of different molecular mass by ultrafiltration demonstrated that GnSAF bioactivity was present in a form 10-30 kDa in size. Incubation for 48 h with these fractions had no significant effect on basal FSH secretion but significantly attenuated GnRH-induced LH secretion during the autumn. The same fractions had little effect on GnRH-induced LH secretion from pituitary cells collected during the summer. We conclude that ovine pituitaries display at least partial reduction in sensitivity to GnSAF outside the breeding season. In addition, neither oestradiol nor progesterone singly or in combination caused the observed attenuation of GnRH-induced LH secretion that is ascribed to GnSAF bioactivity.
引用
收藏
页码:221 / 227
页数:7
相关论文
共 16 条
[1]   IDENTIFICATION OF GONADOTROPIN SURGE-INHIBITING FACTOR (GNSIF) IN FOLLICULAR-FLUID AND ITS DIFFERENTIATION FROM INHIBIN [J].
DANFORTH, DR ;
SINOSICH, MJ ;
ANDERSON, TL ;
CHENG, CY ;
BARDIN, CW ;
HODGEN, GD .
BIOLOGY OF REPRODUCTION, 1987, 37 (05) :1075-1082
[2]   THE SELF-PRIMING ACTION OF LHRH INCREASES THE LOW PITUITARY LH AND FSH RESPONSE CAUSED BY OVARIAN FACTORS - OBSERVATIONS INVITRO [J].
DEKONING, J ;
TIJSSEN, AMI ;
VANREES, GP .
JOURNAL OF ENDOCRINOLOGY, 1989, 120 (03) :439-447
[3]  
FOWLER PA, 1990, J REPROD FERTIL, V90, P587
[4]   PORCINE OVARIAN INHIBIN PREPARATIONS SENSITIZE CULTURED OVINE GONADOTROPHS TO LUTEINIZING-HORMONE-RELEASING HORMONE [J].
HUANG, ES ;
MILLER, WL .
ENDOCRINOLOGY, 1984, 115 (02) :513-519
[5]   DEMONSTRATION OF A NONSTEROIDAL FACTOR IN HUMAN FOLLICULAR-FLUID THAT ATTENUATES THE SELF-PRIMING ACTION OF GONADOTROPIN-RELEASING HORMONE ON PITUITARY GONADOTROPES [J].
KNIGHT, PG ;
LACEY, M ;
PETER, JLT ;
WHITEHEAD, SA .
BIOLOGY OF REPRODUCTION, 1990, 42 (04) :613-618
[6]   ESTRADIOL ALTERS THE EFFECTIVENESS OF GONADOTROPIN-RELEASING HORMONE (GNRH) IN OVINE PITUITARY CULTURES - GNRH RECEPTORS VERSUS RESPONSIVENESS TO GNRH [J].
LAWS, SC ;
WEBSTER, JC ;
MILLER, WL .
ENDOCRINOLOGY, 1990, 127 (01) :381-386
[7]   INHIBIN INCREASES AND PROGESTERONE DECREASES RECEPTORS FOR GONADOTROPIN-RELEASING HORMONE IN OVINE PITUITARY CULTURE [J].
LAWS, SC ;
BEGGS, MJ ;
WEBSTER, JC ;
MILLER, WL .
ENDOCRINOLOGY, 1990, 127 (01) :373-380
[8]   SUPEROVULATION INDUCTION IN WOMEN SUPPRESSES LUTEINIZING-HORMONE SECRETION AT THE PITUITARY LEVEL [J].
MESSINIS, IE ;
TEMPLETON, A .
CLINICAL ENDOCRINOLOGY, 1990, 32 (01) :107-114
[9]  
MESSINIS IE, 1989, J REPROD FERTIL, V87, P633
[10]  
MESSINIS IE, 1991, CLIN ENDOCRINOL, V34, P259