EFFECTS OF AGE AND SEX ON BASAL AND DOPAMINE-INHIBITED IN-VITRO PROLACTIN-RELEASE, AND DOPAMINE-RECEPTOR BINDING, BY THE RAT ADENOHYPOPHYSIS

被引：3
作者：
KOCHMAN, K [1 ]
KOWATCH, MA [1 ]
ROTH, GS [1 ]
BLACKMAN, MR [1 ]
机构：
[1] NIA,GERONTOL RES CTR,MOLEC PHYSIOL & GENET SECT CELLULAR & MOLEC BIOL LAB,BALTIMORE,MD 21224
来源：
AGING-CLINICAL AND EXPERIMENTAL RESEARCH | 1993年 / 5卷 / 05期
关键词：
DOPAMINE; PROLACTIN; RAT ADENOHYPOPHYSIS;
D O I：
10.1007/BF03324186
中图分类号：
R592 [老年病学]; C [社会科学总论];
学科分类号：
03 ; 0303 ; 100203 ;
摘要：
We measured basal and dopamine-inhibited pituitary cell prolactin (PRL) release in vitro, and dopamine receptor binding in pituitary homogenates, from intact male and female Wistar rats of varying ages. During 48-72 hours in culture, the base-line secretion rate of PRL from pituitary cells of old (24 months) male rats was less than one-half that from cells of mature (6 months) male rats, whereas the corresponding basal secretion rate of PRL from cells of old female rats was nearly 3-fold greater than that from cells of mature female rats (p<0.001). After in vitro exposure to various concentrations of dopamine (10(-10)M to 10(-6)M), PRL secretion decreased from pituitary cells of both mature and old rats (p<0.001). However, repeated measures analysis of variance revealed an age-related, dose-dependent decrease in the magnitude of dopamine-inhibited PRL release from cells of both male and female rats (p<0.001). Dopamine receptor number did not differ with age (3-25 months), but was 2 to 3-fold greater in female than in male rats (p<0.01). Receptor affinity was decreased with age only in female rats, and was greater in female than in male rats (p<0.05). These data suggest that the decrease in dopamine-inhibited PRL release from pituitary cells of old male and female rats is not due to altered Pituitary dopamine receptor binding, despite certain sex differences.
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页码：349 / 356
页数：8
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