Crane S C, Morgan B L
Biol Neonate. 1983;43(5-6):234-44. doi: 10.1159/000241650.
The in vitro and in vivo utilization of 14C-beta-hydroxybutyrate (BOHB) by the brain in neonatal hypothyroidism was studied in rat pups made hypothyroid by feeding dams a diet containing 0.02% propylthiouracil during pregnancy and lactation. In the in vitro studies, the oxidation of BOHB to CO2 was lower at 14 and 21 days of age in hypothyroid pups than in pair-fed controls but higher at 35 days. The incorporation of BOHB into brain lipid was significantly higher in hypothyroid pups at 14, 21 and 35 days. In contrast, in the in vivo studies, incorporation of BOHB into lipid was significantly lower in hypothyroid pups at 14 and 21 days. These results suggest that hypothyroid pups may have a normal or increased capability to use BOHB for lipid synthesis, but were unable to achieve normal rates of utilization in vivo, possibly due to a decreased substrate availability. These findings may have implications for the decreased brain lipid content characteristic of neonatal hypothyroidism.
在新生甲状腺功能减退症中，通过在孕期和哺乳期给母鼠喂食含0.02%丙基硫氧嘧啶的饲料，使幼鼠患甲状腺功能减退症，以此研究幼鼠大脑对14C-β-羟基丁酸酯（BOHB）的体外和体内利用情况。在体外研究中，甲状腺功能减退幼鼠在14日龄和21日龄时，BOHB氧化为CO2的量低于配对喂食的对照组，但在35日龄时则较高。在14日龄、21日龄和35日龄时，甲状腺功能减退幼鼠将BOHB掺入脑脂质中的量显著更高。相比之下，在体内研究中，甲状腺功能减退幼鼠在14日龄和21日龄时，将BOHB掺入脂质中的量显著更低。这些结果表明，甲状腺功能减退幼鼠可能具有正常或增强的利用BOHB进行脂质合成的能力，但在体内无法达到正常的利用率，这可能是由于底物可用性降低所致。这些发现可能与新生甲状腺功能减退症特有的脑脂质含量降低有关。
