Methods: The current study was carried on 49 hypertensive rats divided into seven groups, including i) control; ii) L-NAME (10 mg/kg); iii) sodium nitroprusside (SNP) (50 μg/kg) plus L-NAME; iv and v) aqueous fraction of ZJ (150 mg/kg and 300 mg/kg) plus L-NAME; vi) and vii) ethyl acetate fractions of ZJ (150 mg/kg and 300 mg/kg) plus L-NAME. The rats were orally treated with both fractions for four weeks and received intravenous L-NAME on the 28th day. The mean arterial pressure (MAP), systolic blood pressure (SBP) and heart rate (HR) of the rats were recorded then maximal changes (Δ) of MAP, SBP and HR were calculated and compared with changes of control and L-NAME.
Results: According to the obtained results of the present study, it was shown that the administration of L-NAME significantly increased ΔMAP, ΔSBP and ΔHR, and these effects were significantly attenuated by administration of SNP. The pre-treatment with both doses (150 mg/kg and 300 mg/kg) of aqueous and ethyl acetate fractions could significantly reduce cardiovascular responses induced by L-NAME that comparable with SNP. However, a lower dose of aqueous fractions and higher dose of ethyl acetate fractions were reported with stronger effects.
Conclusion: The results of the current study showed that both the aqueous and ethyl acetate fractions of ZJ through the effect on nitric oxide system can prevent the development of HTN induced by L-NAME.
METHODS: Adult male Sprague-Dawley rats were divided into 11 groups; the control group was fed with rat chow, and the other groups were fed with chow that was mixed with 15% weight/weight palm or soy oils, which were either in a fresh form or heated once, twice, five, or ten times. Blood pressures were measured at the baseline and throughout the 24-week study. Plasma nitric oxide levels were assessed prior to treatment and at the end of the study. Following 24 weeks, the rats were sacrificed to investigate their vascular reactivity using the thoracic aorta.
RESULTS: Palm and soy oils had no detrimental effects on blood pressure, and they significantly elevated the nitric oxide contents and reduced the contractile responses to phenylephrine. However, trials using palm and soy oils that were repeatedly heated showed an increase in blood pressure, enhanced phenylephrine-induced contractions, reduced acetylcholine- and sodium nitroprusside-induced relaxations relative to the control and rats that were fed fresh vegetable oils.
CONCLUSIONS: The blood pressure-raising effect of the heated vegetable cooking oils is associated with increased vascular reactivity and a reduction in nitric oxide levels. The chronic consumption of heated vegetable oils leads to disturbances in endogenous vascular regulatory substances, such as nitric oxide. The thermal oxidation of the cooking oils promotes the generation of free radicals and may play an important contributory role in the pathogenesis of hypertension in rats.
Methods: A cross-sectional study was conducted involving 114 Malay patients with POAG seen at the eye clinic of Hospital Universiti Sains Malaysia. Patients aged between 40 and 80 years who were diagnosed with other types of glaucoma, previous glaucoma filtering surgery or other surgeries except uncomplicated cataract surgery and pterygium surgery were excluded. A total of 101 patients who were followed up for dry eyes, age-related cataracts or post cataracts extraction surgery were recruited as control subjects. Those with family history of glaucoma or glaucoma suspect were excluded. Microvascular endothelial function was assessed using laser Doppler fluximetry and the process of iontophoresis. Iontophoresis with acetylcholine (ACh) and sodium nitroprusside (SNP) was used to measure microvascular endothelium-dependent and endothelium-independent vasodilatations, respectively.
Results: In general, POAG patients demonstrated lower ACh% and AChmax values compared with controls. There was significant difference in microvascular endothelial function [ACh%: mean, 95% confidence interval = 503.1 (378.0, 628.3), and AChmax: mean, 95% confidence interval = 36.8 (30.2, 43.5)] between primary open angle glaucoma cases (p