Burt D R, Ajah M A
Gen Comp Endocrinol. 1984 Jan;53(1):135-42. doi: 10.1016/0016-6480(84)90233-8.
The brains of goldfish and other teleosts contain high-affinity binding sites for [3H][3-methyl-His2]thyrotropin-releasing hormone [( 3H]MeTRH) which closely resemble TRH receptors in mammalian brain and pituitary gland in apparent dissociation constant (KD = 3-4 nM), in pharmacology for eight TRH analogs, and in exhibiting marked regional differences in the density of binding sites, with highest binding in the cerebrum and lowest in the cerebellum. Fish brain differs from mammalian brain in containing a prominent additional class of much lower affinity [3H]MeTRH binding sites (KD about 15 microM), of unknown nature, which also exhibit regional differences. Fish pituitary glands contain high-affinity [3H]MeTRH binding sites, but insufficient tissue has prevented full characterization. Little or no saturable binding of [3H]MeTRH was detected in several goldfish peripheral tissues.
金鱼和其他硬骨鱼的大脑含有[3H][3-甲基-His2]促甲状腺激素释放激素[(3H]MeTRH)的高亲和力结合位点，这些位点在表观解离常数(KD = 3 - 4 nM)、8种TRH类似物的药理学特性以及结合位点密度呈现显著区域差异（大脑中结合力最高，小脑中最低）方面，与哺乳动物大脑和垂体中的TRH受体极为相似。鱼类大脑与哺乳动物大脑的不同之处在于，它含有一类额外的、亲和力低得多的[3H]MeTRH结合位点（KD约为15 microM），其性质不明，也表现出区域差异。鱼垂体含有高亲和力的[3H]MeTRH结合位点，但由于组织量不足，无法进行全面表征。在几种金鱼外周组织中，未检测到[3H]MeTRH的饱和结合或仅有少量饱和结合。
