Mechanism of the Stress‐Induced Attenuation of the Testicular Response to Gonadotropin: Possible Involvement of Testicular Opioids, a Pertussis Toxin‐Sensitive G‐Protein, and Phosphodiesterase
Mechanism of the Stress‐Induced Attenuation of the Testicular Response to Gonadotropin: Possible Involvement of Testicular Opioids, a Pertussis Toxin‐Sensitive G‐Protein, and Phosphodiesterase
复制标题
应激引起的睾丸对促性腺激素反应减弱的机制：可能与睾丸阿片类药物、百日咳毒素敏感 G 蛋白和磷酸二酯酶有关
作者：
M. Akinbami;David R. Mann
ABSTRACT: This study examined the potential role of testicular opioids, a pertussis toxin (PT)‐sensitive G‐protein, and phosphodiesterase in mediating the inhibitory effect of immobilization stress on testicular steroidogenesis in adult rats. The experiments were initiated with enriched preparations of Leydig cells, but the stress effect was not sustained in vitro either as a result of the disruption of the morphology of the testis and/or the time required for Leydig cell isolation. Consequently, testicular fragments from control and stressed (3‐hour immobilization) rats were used in these experiments. When fragments from stressed rats were incubated for 2 hours in the absence and presence of human chorionic gonadotropin (hCG) (0.1,1, or 10 mlU), testosterone (T) production in response to 1 and 10 mlU hCG was lower (P < 0.05 and 0.01, respectively) than that from control fragments. Basal T secretion did not differ between stressed and control fragments. Naloxone (1, 10, or 100 μM), did not alter basal or hCG‐stimulated T secretion from control fragments, but it normalized the T response to hCG from stressed fragments. Control fragments also showed a reduced T response (P < 0.05) to hCG in the presence of β‐endorphin (β‐E; 36 nM). Incubation of control fragments with PT (30 ng) did not alter basal or hCG‐stimulated T production. However, PT normalized (P < 0.01) hCG‐stimulated T secretion from stressed fragments. Methytisobutytxanthine (MIX; 0.125 mM) elevated (P < 0.01) hCG‐stimulated T production from control fragments, but hCG‐stimulated T secretion from stressed fragments remained subnormal in the presence of the phosphodiesterase inhibitor. The data suggest that acute immobilization stress inhibits gonadotropin‐induced T production in adult male rats via a mechanism involving testicular opioids and a PT‐sensitive G‐protein. We found no evidence to suggest that a stress‐ induced increase in the activity of phosphodiesterase was involved in this mechanism.
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影响因子：
--
作者：
T. Orr;Taylor Mf;Bhattacharyya Ak;Collins Dc;David R. Mann
通讯作者：
T. Orr;Taylor Mf;Bhattacharyya Ak;Collins Dc;David R. Mann
小鼠 R1.1 胸腺瘤细胞系上表达的 kappa 阿片受体通过百日咳毒素敏感的鸟嘌呤核苷酸结合调节蛋白与腺苷酸环化酶偶联。
DOI：
--
发表时间：
1993
期刊：
The Journal of pharmacology and experimental therapeutics
影响因子：
--
作者：
Lawrence,DM;Bidlack,JM
通讯作者：
Bidlack,JM
影响因子：
3.6
作者：
KLINEFELTER, GR;HALL, PF;EWING, LL
通讯作者：
EWING, LL
束缚应激对大鼠性腺原阿黑皮质素肽和垂体睾丸轴的影响。
影响因子：
6.1
作者：
Mann,DR;Orr,TE
通讯作者：
Orr,TE