Zoology Section, Mahila Mahavidyalaya, Banaras Hindu University, Varanasi, India.
Fish Physiol Biochem. 2012 Jun;38(3):757-67. doi: 10.1007/s10695-011-9558-0. Epub 2011 Oct 15.
Neurosteroids are those which are synthesized in the central nervous system independently of supply by peripheral endocrine glands. In the present study, brain contents of the steroid hormones, estradiol-17β (E(2)), testosterone (T), corticosteroids, and progestins were investigated in both male and female catfish Heteropneustes fossilis in prespawning (vitellogenic) and spawning (post-vitellogenic) phases using ELISA or HPLC. The data show that the measured steroid hormones showed both stage-specific and sex-related variations. Brain E(2) was significantly higher in males in the prespawning phase and in females in the spawning phase. Testosterone was significantly higher in males in comparison with females in the prespawning phase. Cortisol was significantly higher in the prespawning and spawning phases in males than in females. Corticosterone level was low in the brain. 21-deoxycortisol and deoxycorticosterone were significantly higher in the prespawning phase than in the spawning phase. Male brain recorded the highest concentration of deoxycorticosterone. Progesterone (P(4)) was high in the prespawning phase and low in the spawning phase in both sexes. Levels of 17-hydroxy-4-pregnene-3,20-dione and 17,20β-dihydroxy-4-pregnen-3-one (17,20β-DP) and the metabolites of P(4) were the highest in females in the prespawning phase. The stage-specific and sexual differences in the content of the steroids suggest their biosynthesis in the brain, which may have implications in brain functions, in addition to reproductive regulation.
神经甾体是指在中枢神经系统中独立于外周内分泌腺供应而合成的甾体。在本研究中，采用 ELISA 或 HPLC 法检测了处于产卵前期（卵黄生成期）和产卵期（产卵后期）的雄性和雌性鲶鱼 Heteropneustes fossilis 脑中的甾体激素雌二醇-17β（E(2)）、睾酮（T）、皮质类固醇和孕激素的含量。结果表明，所测甾体激素均表现出阶段特异性和性别相关性变化。产卵前期雄性脑中 E(2)明显高于雌性，产卵期雌性脑中 E(2)明显高于雄性。产卵前期雄性脑中睾酮明显高于雌性。与雌性相比，雄性在产卵前期和产卵期的皮质醇水平均较高。脑内皮质酮水平较低。21-脱氧皮质醇和脱氧皮质酮在产卵前期明显高于产卵后期。雄性脑记录的脱氧皮质酮浓度最高。孕酮（P(4)）在产卵前期雌性和雄性中均较高，而在产卵后期则较低。17-羟-4-孕烯-3,20-二酮和 17,20β-二羟-4-孕烯-3-酮（17,20β-DP）以及 P(4)的代谢产物在产卵前期雌性中含量最高。甾体含量的阶段特异性和性别差异表明其在脑中的生物合成，这可能对脑功能具有重要意义，除了对生殖调节的影响。
