Evaluation of the CaV1 1-R528 H gene knock-in mouse model of thyrotoxic hypokalemic periodic paralysis / 中国实验动物学报

Objective To establish and evaluate the CaV1?1?R528H gene knock?in mouse model of thyrotoxic hy?pokalemic periodic paralysis. Methods Thirty?six 8?week?old male CaV1?1?R528H gene knock?in mice and thirty?six 8?week?old wild?type male C57BL/6J mice were used in this study. Using three?factor two?level 2 × 2 × 2 factorial design ( the three factors including mutation, thyroxine and insulin, and two levels were with or without) , the mice were divided into 8 groups. The thyroxine groups were intraperitoneally injected with levothyroxine in a dose of 350 μg/kg once per day for 12 consecutive days to produce thyrotoxicosis. The insulin groups were intraperitoneally injected with short?acting insulin in a dose of 0?8 U/kg after the last administration of levothyroxine, and the potassium levels of different groups were meas?ured and recorded before (0 min) and after insulin injection (30 min, 60 min). Results (1) Compared with the control group, the following phenomena including irritability, dull coat, increased diet and water intake, and slow body weight gain, were observed in the thyrotoxic mice. Thyroid function tests showed that the levels of T3 and T4 in the thyrotoxic mice were significantly higher than those in the corresponding control mice (P<0?05), and the TSH level was significantly low?er than that of the corresponding control mice (P<0?05 ). (2) After administration of insulin or thyroxine alone, the po?tassium levels in the mutant and wild?type mice were not significantly different. However, after combined administration of thyroxine and insulin, the potassium levels in the mutant group were significantly lower than those in the wild?type mice at 30 min and 60 min ( P<0?05 for both). (3) The main effects and interactions:Mutation factor or thyroxine factor alone did not influence on the potassium level, only insulin showed hypokalemic effect (P<0?05). There were interactions be?tween thyroxine and mutation, and between insulin and mutation (P<0?05), but no interaction between thyroxine and in?sulin. Conclusions (1) A thyrotoxicosis state in mice is successfully developed in this study. (2) An CaV1?1?R528H gene knock?in mouse model of thyrotoxic hypokalemic periodic paralysis is successfully established.

Thyrotoxic Periodic Paralysis Associated with Transient Thyrotoxicosis Due to Painless Thyroiditis

Thyrotoxic periodic paralysis (TPP) is a rare manifestation of hyperthyroidism characterized by muscle weakness and hypokalemia. All ethnicities can be affected, but TPP typically presents in men of Asian descent. The most common cause of TPP in thyrotoxicosis is Graves' disease. However, TPP can occur with any form of thyrotoxicosis. Up to our knowledge, very few cases ever reported the relationship between TPP and painless thyroiditis. We herein report a 25-yr-old Korean man who suffered from flaccid paralysis of the lower extremities and numbness of hands. The patient was subsequently diagnosed as having TPP associated with transient thyrotoxicosis due to painless thyroiditis. The paralytic attack did not recur after improving the thyroid function. Therefore, it is necessary that early diagnosis of TPP due to transient thyrotoxicosis is made to administer definite treatment and prevent recurrent paralysis.

Parálisis periódica tirotóxica / Thyrotoxic periodic paralysis

Presentamos el caso de un hombre de 39 años quien sufrió dos episodios de parálisis por hipocaliemia asociado a hipertiroidismo. Esta entidad inusual y considerada casi exclusiva de los países asiáticos también ha sido documentada en países occidentales; por tanto, damos a conocer este caso para ser tenido en cuenta entre los diagnósticos diferenciales en los servicios de urgencias (Acta Med Colomb 2011; 36: 145-148).

We recorded the case of a 39 year-old man who suffered two episodes of paralysis and hipokalemia associated with hyperthyroidism. This unusual entity, almost exclusively of asian countries, has been documented in western countries; therefore, we present this case to be considered in the differential diagnosis in emergency departments (Acta Med Colomb 2011; 36: 145-148).