Deficiency of the human complement regulatory protein factor H associated with low levels of component C9.

We identified a 4-year-old Brazilian boy from a family of Japanese descent and history of consanguinity, who suffered from severe recurrent pneumonia. He carries factor H (FH) deficiency associated with reduced levels of component C9 and low serum levels of C3 and factor B. His mother also presented low levels of these proteins and factor I, while his father and sister had only lower levels of FH. Western blot assays confirmed the complete absence of FH and FHL-1 polypeptides in this patient. Sequencing of the proband's FH cDNA revealed a homozygous G453A substitution, encoding an Arg(127)His change. His mother, father and sister are heterozygous for this substitution. Despite the absence of FH in the plasma, this protein was detected in the patient's fibroblasts, suggesting that Arg(127) may be important for FH secretion. Low concentrations of C9 were detected in the proband serum but no mutations in the patient's C9 gene or promoter have been identified, suggesting that this is a consequence of uncontrolled complement activation and high C9 consumption.

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.

Influence of a multideficient diet from northeastern Brazil on resting blood pressure and baroreflex sensitivity in conscious, freely moving rats.

The "regional basic diet" or RBD is a multideficient diet (providing 8% protein) which is known to produce dietary deficiencies in some populations in northeastern Brazil. The present study investigated the effects of RBD-induced malnutrition on resting blood pressure and baroreflex sensitivity in conscious rats. Malnourished rats were obtained by feeding dams the RBD during mating and pregnancy (RBD-1 group) or during nursing and a 10-day period after weaning (RBD-2 group). At 90 days of age, only RBD-2 rats weighed significantly (P<0.001) less than control rats born to dams fed a standard commercial diet (23% protein) during pregnancy and nursing. Baseline mean arterial pressure and heart rate of both RBD-1 and RBD-2 rats were comparable to those of controls. The slopes for both reflex bradycardia and tachycardia (bpm/mmHg) induced by intravenous phenylephrine and sodium nitroprusside, respectively, were unchanged in either RBD-1 (-2.08 +/- 0.11 and -3.10 +/- 0.43, respectively) or RBD-2 (-2.32 +/- 0.30 and -3.73 +/- 0.53, respectively) rats, when compared to controls (-2.09 +/- 0.10 and -3.17 +/- 0.33, respectively). This study shows that, after a prolonged period of nutritional recovery, the patterns of resting blood pressure and baroreflex sensitivity of both pre- and postnatally malnourished rats were similar to those of controls. The decreased body weight and the tendency to increased reflex tachycardia in RBD-2 rats may suggest that this type of maternal malnutrition during lactation is more critical than during pregnancy.

Influence of a multideficient diet from northeastern Brazil on resting blood pressure and baroreflex sensitivity in conscious, freely moving rats

The "regional basic diet" or RBD is a multideficient diet (providing 8 percent protein) which is known to produce dietary deficiencies in some populations in northeastern Brazil. The present study investigated the effects of RBD-induced malnutrition on resting blood pressure and baroreflex sensitivity in conscious rats. Malnourished rats were obtained by feeding dams the RBD during mating and pregnancy (RBD-1 group) or during nursing and a 10-day period after weaning (RBD-2 group). At 90 days of age, only RBD-2 rats weighed significantly (P<0.001) less than control rats born to dams fed a standard commercial diet (23 percent protein) during pregnancy and nursing. Baseline mean arterial pressure and heart rate of both RBD-1 and RBD-2 rats were comparable to those of controls. The slopes for both reflex bradycardia and tachycardia (bpm/mmHg) induced by intravenous phenylephrine and sodium nitroprusside, respectively, were unchanged in either RBD-1 (-2.08 0.11 and -3.10 0.43, respectively) or RBD-2 (-2.32 0.30 and -3.73 0.53, respectively) rats, when compared to controls (-2.09 0.10 and -3.17 0.33, respectively). This study shows that, after a prolonged period of nutritional recovery, the patterns of resting blood pressure and baroreflex sensitivity of both pre- and postnatally malnourished rats were similar to those of controls. The decreased body weight and the tendency to increased reflex tachycardia in RBD-2 rats may suggest that this type of maternal malnutrition during lactation is more critical than during pregnancy