Effect of Triiodothyronine Administration on the Kidney During Haemorrhagic Shock and Resuscitation
TURKISH JOURNAL OF ANAESTHESIOLOGY AND REANIMATION
Authors: Karmaniolou, Iosifina; Lamprou, Konstantinos; Staikou, Chryssoula; Giamarellos-Bourboulis, Evangelos; Theodoraki, Kassiani; Papalois, Apostolos; Mylonas, Anastasios; Orfanos, Nikolaos; Smyrniotis, Vassilios; Arkadopoulos, Nikolaos
Objective: Apoptosis, measured via caspase activity, can be used to assess renal tissue damage in haemorrhagic shock. We investigated whether Triiodothyronine could attenuate apoptosis and protect against haemorrhagic shock-induced renal injury. Methods: Haemorrhagic shock was induced in swine until the mean arterial pressure (MAP) was 35-40 mmHg for 40 minutes. Animals were randomly assigned to a control group (n=5), Group-F (Fluid resuscitation, n=6), and Group-T3 (Fluid plus Triiodothyronine, n=6). The swine were resuscitated for 1 hour aiming to MAP restoration (+/- 10% from baseline) and were followed up for another 360 minutes. Haemodynamic parameters, fluids, acid-base status, plasma urea nitrogen, creatinine levels and caspase activity in the kidney were measured. Results: Haemodynamic parameters did not differ significantly amongst the three groups. Group-T3 required less normal saline ( Group-T3: 1083 +/- 204 mL versus F: 2500 +/- 547 mL, p= 0.001) and hydroxyethyl starch (Group-T3: 558 +/- 102 mL versus F: 916 +/- 204 mL, p=0.004) during resuscitation. Additionally, Group-T3 swine experienced less acidosis following haemorrhage/resuscitation with a pH of 7.39 versus a pH of 7.26 in Group-F (p=0.004) at 360 minutes. Urea remained within normal limits in all groups, but creatinine levels were elevated at 6 hours in Group-F as compared to Group-T3 (p=0.019). Apoptosis, assessed by renal caspase-3 activity, was increased in Group-T3 (132 +/- 174 pmol minute(-1) g(-1)) and reduced in Group-F (32 +/- 18 pmol minute(-1) g(-1)) as compared to the control group, but without statistical significance (p=0.245 between Group-T3 and Group-F). Conclusion: Administration of Triiodothyronine in a swine model of haemorrhagic shock seems to interfere with renal cell apoptosis. The exact mechanism needs to be further investigated in future research.
Postpartum pulmonary circulation in pregnant rats with monocrotaline-induced pulmonary arterial hypertension
JOURNAL OF THORACIC DISEASE
Authors: Jing, He; Jin, Mu; Li, Yue; Sun, Yuwei; Lu, Jiakai; Cheng, Weiping
Background: This is the first study to evaluate changes in postpartum pulmonary circulation in a novel pregnant rat model of monocrotaline (MCT)-induced pulmonary arterial hypertension (PAH). Methods: Female rats were randomly divided into two groups: the MCT-treated pregnant group, in which rats were injected with MCT (40 mg/kg) at the age of 7 weeks, and the pregnant group, in which rats were injected with the same volume of 0.9% saline at the same age. Rats from both groups were mated at the age of 9 weeks. General condition information, hemodynamic data and pulmonary tissues were collected from pregnant rats from the two groups on the 18th day after successful mating (T1) and the 1st (T2), 3rd (T3), and 7th days after delivery (T4). Results: The MCT-treated pregnant group exhibited a greater mean pulmonary artery pressure (mPAP) (P<0.01) and Fulton's Index (P<0.01) than the pregnant group at each time point. Lung tissues from the MCT-treated pregnant group showed pulmonary vascular hyperplasia and occlusive changes. The mPAP and the occluded pulmonary artery density in the MCT-treated pregnant group increased after delivery (P<0.01) and significantly increased at T3 compared with T2 (P<0.05) but was not further increased at T4 (P>0.05). Conclusions: Pregnant rats with PAH exhibited increased mPAP after delivery accompanied by a significant increase in the occluded pulmonary artery density, which may have contributed to the increased mortality rate of pregnant rats with PAH after delivery.