Publications by authors named "Aloamaka C"

The cellular integrity of the kidney in homeostatic regulation has constantly been compromised by oxidative stress following exposure to varying nature of stressor present within the environment. The objective of the work was to evaluate the renal effect of the different stressor stimuli applied. Twenty-four adult female rats weighing averagely 160-200 g and within the ages of 12-14 weeks were used for experiment-1, while 12 offspring were utilized for experiment-2.

View Article and Find Full Text PDF

This study was designed to physiologically investigate the fate of stress related infertility conditions to focus on the regulatory response of reproductive potentials in stress-induced female Wistar rats supplemented with clomifene citrate. 42 apparently healthy female Wistar rats weighing about 120-160 g were used in the study. The animals were randomly distributed into 3 groups after acclimatization for 2 weeks.

View Article and Find Full Text PDF

Infertility is generally regarded as a major clinical problem, and it adversely affects people both psychologically and medically. In this study, the changes in gonadal oxidative stress markers and reproductive function of BALB/c mice were investigated. Forty-eight (48) BALB/c mice acquired for this study were randomly divided into four (4) groups of eight (8) mice each.

View Article and Find Full Text PDF

Crude ethanolic extracts of the leaves of Sorghum bicolor L. Moench were used as stains for tissue sections. The alkaline mixtures did not stain any of the tissues used but the acidic and neutral alcoholic mixtures stained collagen fibres, muscles and red blood cells in shades of pinkish-yellow.

View Article and Find Full Text PDF

The vascular effects of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), a meperidine analog, were studied in vitro on ring preparations of rat aorta for the purpose of characterizing its mode of action. Isometric contractions were evaluated under standard organ bath conditions. Exposure to MPTP (10(-12)-1.

View Article and Find Full Text PDF

The vasorelaxant effects of acetylcholine (Ach) and histamine have been examined on 10(-7) M-noradrenaline (NA)-precontracted ring preparations of epigastric arteries from normotensive and pregnancy-induced hypertensive women. Contractile responses to 10(-7) M-NA were significantly (p < 0.05) enhanced following removal of the endothelium.

View Article and Find Full Text PDF

This study characterises the reactivity of chorionic plate artery in pre-eclampsia to prostaglandin F2 alpha (PGF2 alpha), 5-hydroxytryptamine (5-HT), and potassium chloride (KCl) and examines the role of the vascular endothelium in these responses. Ring segments of the chorionic plate arteries of women after normal and pre-eclamptic pregnancies were contracted by PGF2 alpha, 5-HT, and KCl. The experiments were carried out in the presence and absence of endothelium, and on intact rings treated with 10(-6)M indomethacin.

View Article and Find Full Text PDF

The influence of plasma from pregnant and nonpregnant humans was examined, using magnesium-induced relaxation of precontracted rat aortic rings. The results showing magnesium-induced relaxation of aortic rings from pregnant and nonpregnant rats were compared. In rat aortic rings incubated in plasma from pregnant patients, magnesium was more potent in relaxing the precontractions induced by potassium chloride than in relaxing those induced by phenylephrine.

View Article and Find Full Text PDF

The study examined the effect of salt-induced hypertension on vascular relaxation in response to magnesium sulphate during pregnancy. Pregnant Wistar rats were fed for 6 weeks on a diet containing 0.3% (control) and 8.

View Article and Find Full Text PDF

We have examined the influence of prostanoid synthesis inhibitors on the relaxation responses induced by cicletanine in ring preparations of isolated human epigastric arteries following precontraction induced by 10(-7) M noradrenaline. Cicletanine caused concentration-dependent relaxations, uninfluenced by the cyclooxygenase inhibitors, meclofenamate (1, 10 microM) and indomethacin (1, 10 microM) but significantly (p < 0.05) attenuated by the specific prostacyclin synthesis inhibitor, tranylcypromine (0.

View Article and Find Full Text PDF

Salt-induced high blood pressure in diabetic rats was compared with that in non-diabetic (control) rats. Before the rats had eaten the high-salt diet, the diabetic group exhibited significantly greater pressor response to noradrenaline (100 ng/100 g body weight) than the controls (P < 0.05).

View Article and Find Full Text PDF

The effect of pregnancy on the supply of calcium ions for the contractile responses of rat aortic rings to phenylephrine was investigated. The contractility of intact aortic rings from pregnant rats, compared with that of similar rings from non-pregnant rats, to phenylephrine and potassium chloride was significantly decreased. Contractions of rings from non-pregnant rats, pretreated with phenylephrine or potassium chloride, in response to calcium chloride were greater than those of similarly treated rings from pregnant rats.

View Article and Find Full Text PDF

Objective: There is evidence for involvement of the endothelium in magnesium induced vasodilatation. In view of the use of magnesium in the treatment of women with pre-eclampsia, and because the mechanism of the vascular effects of magnesium in pregnancy is not fully understood, this study examined the dilator response to magnesium of aortic rings from pregnant and non-pregnant rats. The role of the endothelium was also evaluated.

View Article and Find Full Text PDF

Sodium-potassium ATPase activity and transmembrane calcium influx in the aortic smooth muscle from control and diabetic rats were assessed indirectly through the measurement of KCl relaxation and contractile responses to CaCl2 in attempts to explain the contractile responses to KCl following streptozotocin-induced diabetes mellitus. There were no significant changes in the maximum contractile responses of the aortas from 4 and 12 week diabetic rats to KCl even when significant increases in calcium influx were demonstratable. On the other hand, the diabetic aortas were significantly (P < 0.

View Article and Find Full Text PDF

1. The effects of normal human pregnant plasma on the reactivity of rabbit aortic rings with documented endothelium have been studied. The rings were incubated in plasma from either normal pregnant or non-pregnant women and the effects of incubation on their responses to noradrenaline (NA), calcium chloride stimulation and potassium chloride-induced relaxation were examined.

View Article and Find Full Text PDF

The role of endothelium in the decreased contraction to phenylephrine in aorta of pregnant Wistar rats has been studied. Contractions in response to phenylephrine were significantly decreased in aortic rings from pregnant rats compared to those from non-pregnant rats. Pretreatment of the rings with indomethacin did not significantly alter the pattern of responses.

View Article and Find Full Text PDF

1. The relaxations of aortic preparations from 1, 4 and 12 week diabetic rats to acetylcholine and histamine were studied. 2.

View Article and Find Full Text PDF

1. The responsiveness of aortic rings from 4 and 12 week streptozotocin-induced diabetic rats to D600 (Gallopamil) and nifedipine was studied. 2.

View Article and Find Full Text PDF

1. The responsiveness of isolated aortic rings from 1, 4 and 12 week streptozotocin-induced diabetic rats to noradrenaline (NA) and 5-hydroxytryptamine (5-HT) were compared with those of non-diabetic controls under standard organ bath procedure. 2.

View Article and Find Full Text PDF

The involvement of endothelium in the contractile responses of rat aortic rings to phenylephrine and potassium chloride in pregnancy was examined. Contractions in response to both agents were significantly greater in rings from non-pregnant rats than in rings from pregnant rats, and they were unaltered by treatment of the rings with indomethacin. De-endothelialization potentiated the contractions of rings from pregnant rats in response to phenylephrine, but had no significant effect on similar rings contracted with potassium chloride.

View Article and Find Full Text PDF

1. The contractile responses of aortic ring preparations from Sprague-Dawley rats made hypertensive by 6-week dietary salt loading were studied. The test and control diet contained 8.

View Article and Find Full Text PDF

The inhibitory effect of dichlorovos (an organophosphate pesticide) on Ca(2+)-dependent contractions has been studied in isolated helical strips of rat tail arteries. Isometric contractions were evaluated under standard organ bath conditions. Dichlorovos caused concentration-dependent relaxation of 10(-7) M NE-induced contractions as well as inhibition of both phasic and tonic components of NE contractions.

View Article and Find Full Text PDF

The mechanism of Ba2+-induced contraction has been examined in helical strips of Ca2+-depleted, 60 mM K+-depolarized rat aortae. The concentration-response curves to Ca2+ or Ba2+ were significantly potentiated by exposure to 3 X 10(-8) M Bay K 8644 (a Ca2+ channel agonist) in the order Ca2+ greater than Ba2+, suggesting an action of Ba2+ ions through potential-sensitive membrane Ca2+ channels. Exposure of strips to background concentration of Ca2+ (0.

View Article and Find Full Text PDF