High blood pressure is one of the symptoms of paraquat-induced toxicity in rats.

This study investigated whether paraquat (Pq)-induced lipidic peroxidation (LP) is accompanied by changes in blood pressure and heart rate (HR) in rats. Groups of adult male Wistar rats were studied 2 and 12 h after Pq (35 mg/kg, i.p.) administration. The LP was evaluated by monitoring thiobarbituric acid reactive substances (TBARS) in the kidneys, liver and lungs, and validated by including a group treated with an antioxidant, superoxide dismutase (CuZnSOD 50,000 IU/kg), in the study. The TBARS levels were significantly higher (p<0.05) in the kidneys of the rats studied 2 h after Pq than in their respective controls. Similarly, systolic and diastolic blood pressure (DBP) were higher (p<0.05), while HR was lower (p<0.05) than basal levels 2 and 12 h after Pq administration. In contrast, the group treated simultaneously with Pq and CuZnSOD exhibited lower levels of TBARS (p<0.05) in all studied organs compared to the control group, while the mean arterial pressure and HR did not differ from those seen in the control group. These findings indicate that acute Pq poisoning symptoms include high blood pressure.

Cholesterol and phospholipids content of yolk from fertilized and unfertilized hen eggs.

Three lipid-containing fractions (granules, low-density lipoproteins (LDL) and infranatant) of fertilized and unfertilized yolks were obtained from hen eggs, either from commercial sources or from Arbor acres hens kept by the Pena Branca Aviário Pernambuco and utilized fresh (laid during the previous 7 days). Total cholesterol (TC) and total phospholipid (TP) levels (mg/g yolk, reported as means +/- SD) were determined. In the yolk granules (insoluble fraction) the levels of TC (2.05 +/- 0.36) and TP (0.90 +/- 0.43) of fertilized egg yolks were similar to the levels of TC (2.20 +/- 0.41) and TP (0.90 +/- 0.14) of unfertilized eggs. The TC levels in the LDL from fertilized egg yolks (8.29 +/- 1.63) were not statistically different from those in unfertilized eggs (7.31 +/- 1.50). In contrast, TC was not detected in the infranatant fraction of unfertilized egg yolks, but was present in the infranatant fraction (1.39 +/- 0.69) of fertilized eggs. The TP levels of LDL (0.73 +/- 0.23) and infranatant (0.32 +/- 0.09) fractions of fertilized egg yolks were significantly lower than the levels of TP in the LDL (1.73 +/- 0.51) and infranatant (0.79 +/- 0.59) fractions of unfertilized eggs. Consequently, the TC/TP ratio (mol/mol) increased in the LDL and infranatant fractions of fertilized egg yolks when compared to unfertilized egg yolks. TC levels were similar in the total yolk of fertilized (10.76 +/- 1.32) and unfertilized (10.33 +/- 1.77) eggs, while the TP levels were significantly lower in the fertilized (1.92 +/- 0.17) than in unfertilized (3.43 +/- 0.97) eggs.(ABSTRACT TRUNCATED AT 250 WORDS)

Cholesterol and phospholipids content of yolk from fertilized and unfertilized hen eggs

Three lipid-containing (granules, low-density lipoproteins (LDL) and infranatant) of fertilized and unfertilized yolks were obtained from hen eggs, either from commercial sources or from Arbor acres henskept by the Pena Branca Aviario Pernambuco and utilized fresh (laid during the previous 7 days). Total cholesterol (TC) and total phospholipid (TP) levels (mg/g yolk, reported as means ñ SD) were determined. In the yolk granules (insoluble fraction) the levels of TC (2.05 ñ 0.36) and TP(0.90 ñ 0.43) of fertilized egg yolks were similar to the levels of TC (2.20 ñ 0.4) and TP (0.90 ñ 0.14) of unfertilized eggs. The levels TC in the LDL from fertilized egg yolks (8.29 ñ 1.63) were not statistically different from those in unfertilized eggs (7.31 ñ 1.50). In contrast, TC was not detected in the infranatant fraction of unfertilized egg yolks, but was present in the infranatant fraction (1.39 ñ 0.69) of fertilized eggs. The TP levels of LDL (0.73 ñ 0.23) and infranatant (0.32 ñ 0.09) fractions of fertilized egg yolks were significantly lower than the levels of TP in the LDL (1.73 ñ 0.51) and infranatant (0.79 ñ 0.59) fractions of unfertilized eggs. Consequently, the TC/TP ratio (mol/mol) increased in the LDL and infranatant fractions of fertilized egg yolks when compared to unfertilized egg yolks. TC levels were similar in the total yolks TC levels were similar in the total yolk of fertilized (10.76 ñ 1.32) and unfertilized (10.33 ñ 1.77) eggs, while the TP levels were significantly lower in the fertilized (1.92 ñ 0.17) than in unfertilized (3.43 ñ 0.97) eggs. These results suggest a transfer of TC from the LDL to the infranatant fraction and a large consumption of TP during the fertilization process

Studies on rat liver mitochondria. II. Formation of lipid peroxides in mitochondria preserved at 0-4 degrees C.

Levels of lipid peroxides were monitored in freshly isolated rat liver mitochondria, aged mitochondria, and preserved mitochondria by reaction with TBA (2-thiobarbituric acid) and spectrophotometric absorption at 233 nm. In aged mitochondria, the levels of lipid peroxides increased gradually during 120 hr, while in preserved mitochondria they increased rapidly up to 24-48 hr. Under such conditions, the respiratory control coefficients and the levels of total Pi were about 40% those of fresh mitochondria, and the decrease of the levels of lipid peroxides followed the decrease of the respiratory control coefficients and levels of total Pi. These results suggest that stimulation of the formation of lipid peroxides occurs when the vital activity of mitochondria is preserved.