King P A, Beyenbach K W, Goldstein L
J Exp Zool. 1982 Oct 10;223(2):103-14. doi: 10.1002/jez.1402230202.
Previous in vivo clearance studies (Schrock et al., '82) have revealed that taurine is secreted by marine fish kidneys. In the present study taurine secretion by the flounder (Pseudopleuronectes americanus) renal tubule was investigated by assaying the transport of 14C-taurine in vitro. Collections from isolated fluid-secreting flounder tubules confirmed the presence of a tubular mechanism for taurine secretion. The flounder renal tubule concentrated taurine in the lumen at a lumen/bath ratio of 25, with the movement across the peritubular membrane identified as the concentrating step of taurine transport. Studies with teased flounder renal tubules identified transport as Na+ and C1- dependent. Taurine transport was inhibited by beta alanine, gamma-aminobutyric acid, and hypotaurine. In a study of the hormonal control of taurine transport, only the adrenal steroid dexamethasone stimulated taurine uptake by the flounder renal tubules. Transport was not affected by the second messengers adenosine 3'5'-cyclic monophosphate, guanosine 3'5'-cyclic monophosphate, adenosine, or Ca++ ionophore (A12384).
先前的体内清除研究（施罗克等人，1982年）表明，牛磺酸由海鱼肾脏分泌。在本研究中，通过体外测定14C-牛磺酸的转运，对牙鲆（美洲拟庸鲽）肾小管分泌牛磺酸的情况进行了研究。从分离出的分泌液体的牙鲆肾小管收集的样本证实了存在牛磺酸分泌的管状机制。牙鲆肾小管以管腔/浴液比例为25在管腔中浓缩牛磺酸，确定跨肾小管周围膜的移动为牛磺酸转运的浓缩步骤。对分离的牙鲆肾小管的研究确定转运依赖于Na+和Cl-。牛磺酸转运受到β-丙氨酸、γ-氨基丁酸和次牛磺酸的抑制。在一项关于牛磺酸转运的激素控制的研究中，只有肾上腺类固醇地塞米松刺激牙鲆肾小管摄取牛磺酸。转运不受第二信使3',5'-环磷酸腺苷、3',5'-环磷酸鸟苷、腺苷或Ca++离子载体（A23187）的影响。
