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Cristina Ogrin

Publications and source records attributed to Cristina Ogrin.

5 recordsLinked to original sources

Suppression of thyrotropin by morphine in a severely stressed patient.

Opiates suppress TSH in experimental animals but are reported to increase TSH in human subjects. We describe a patient in severe pain treated with morphine, whose previously normal TSH fell to a level usually associated with hyperthyroidism. After returning to a normal concentration, TSH again decreased with morphine administration. This suggests that, in contrast to the stimulation of TSH secretion that has been reported in unstressed experimental subjects, morphine can inhibit TSH secretion during stress in man as it does in experimental animals. This observation is consistent with the known sensitization of opiate receptors by stress. Consideration should be given to the possibility that severe suppression of TSH by opiates in stressed patients may induce clinically significant central hypothyroidism.

Back Pain↗

Abrogation of oxidative stress improves insulin sensitivity in the Ren-2 rat model of tissue angiotensin II overexpression.

To evaluate the role of renin-angiotensin system (RAS)-mediated oxidative stress in insulin resistance (IR), we compared the effects of the angiotensin II (ANG II) receptor blocker (ARB) valsartan and a superoxide dismutase (SOD) mimetic, tempol, on whole body glucose tolerance and soleus muscle insulin-stimulated glucose uptake in transgenic hypertensive TG(mREN-2)27 (Ren-2) rats. Ren-2 rats and Sprague-Dawley (SD) controls were given valsartan (30 mg/kg) or tempol (1 mmol/l) in their drinking water for 21 days. IR was measured by glucose tolerance testing (1 g/kg glucose ip). IR index (AUC(glucose) x AUC(insulin)) was significantly higher in the Ren-2 animals compared with SD controls (30.5 +/- 7.0 x 10(6) arbitrary units in Ren-2 vs. 10.2 +/- 2.4 x 10(6) in SD, P < 0.01). Both valsartan and tempol treatment normalized Ren-2 IR index. Compared with SD controls (100%), there was a significant increase in superoxide anion production (measured by lucigenin-enhanced chemiluminescence) in soleus muscles of Ren-2 rats (133 +/- 15%). However, superoxide production was reduced in both valsartan- and tempol-treated (85 +/- 22% and 59 +/- 12%, respectively) Ren-2 rats. Insulin (INS)-mediated 2-deoxyglucose (2-DG) uptake (%SD basal levels) was substantially lower in Ren-2 rat soleus muscle compared with SD (Ren-2 + INS = 110 +/- 3% vs. SD + INS = 206 +/- 12%, P < 0.05). However, Ren-2 rats treated with valsartan or tempol exhibited a significant increase in insulin-mediated 2-DG uptake compared with untreated transgenic animals. Improvements in skeletal muscle insulin-dependent glucose uptake and whole body IR in rats overexpressing ANG II by ARB or SOD mimetic indicate that oxidative stress plays an important role in ANG II-mediated insulin resistance.

Administration, Oral↗