Jarzab B, Kaminski M, Gubala E, Achtelik W, Wagiel J, Döhler K D
Department of General Biology, Silesian Academy of Medicine, Katowice, Poland.
Brain Res. 1990 May 21;516(2):257-62. doi: 10.1016/0006-8993(90)90926-3.
Sexual differentiation of the brain seems to be influenced by postnatal interaction of gonadal steroids with neurotransmitter systems, in particular the adrenergic system. Stimulation or inhibition of adrenergic receptors during early postnatal development had previously been shown to influence steroid-induced sexual differentiation of rat brain function. In the present study newborn male and female rats were treated daily for 5 days with salbutamol, a specific beta 2-receptor agonist, or with alprenolol, a beta-receptor antagonist and the volume of the sexually dimorphic nucleus of the preoptic area (SDN-POA) was examined in adulthood. This nucleus, one of the most striking sex differences in brain anatomy, is several-fold larger in male than in female rats. Postnatal treatment with salbutamol increased SDN-POA volume in female and in male rats. The effect was particularly striking in males, because any previous pre- and/or postnatal treatment of male rats with large amounts of gonadal steroids had been unable to increase the volume of the SDN-POA above normal. The beta-receptor antagonist alprenolol had no effect on SDN-POA differentiation. The results indicate that beta 2-adrenergic stimulation influences development and differentiation of the SDN-POA.
大脑的性别分化似乎受到性腺类固醇与神经递质系统，特别是肾上腺素能系统产后相互作用的影响。先前的研究表明，在出生后早期发育过程中刺激或抑制肾上腺素能受体会影响类固醇诱导的大鼠脑功能性别分化。在本研究中，对新生雄性和雌性大鼠每天用沙丁胺醇（一种特异性β2受体激动剂）或阿普洛尔（一种β受体拮抗剂）处理5天，并在成年后检查视前区性二态核（SDN-POA）的体积。这个核是大脑解剖学中最显著的性别差异之一，在雄性大鼠中比雌性大鼠大几倍。产后用沙丁胺醇处理可增加雌性和雄性大鼠的SDN-POA体积。这种效应在雄性大鼠中尤为显著，因为之前对雄性大鼠进行的任何产前和/或产后大量性腺类固醇处理都无法使SDN-POA的体积超过正常水平。β受体拮抗剂阿普洛尔对SDN-POA的分化没有影响。结果表明，β2肾上腺素能刺激会影响SDN-POA的发育和分化。
