Vitamin E attenuates nicotine- and noise-induced reproductive impairment in male albino Wistar rats.

Previous studies showed that exposure to stress or nicotine induced reproductive impairment in male rats. Here, we assessed the effect of an antioxidant (vitamin E) on nicotine-, stress- and nicotine + stress-induced reproductive impairment in male rats. Forty-eight male albino Wistar rats were divided into eight groups as follows; control, stress (generator noise 90-120 dB, 8 hr/day), nicotine (1.5 mg kg-1 day-1 ), nicotine + stress, vitamin E (100 mg kg-1 day-1 ), stress + vitamin E, nicotine + vitamin E and stress + nicotine + vitamin E. Sperm count, viability, motility and rapid progressive forward movement decreased significantly (p < 0.05), while percentage of nonmotile spermatozoa increased significantly (p < 0.05) in stress, nicotine and nicotine + stress groups, compared with control. Serum testosterone and follicle-stimulating hormone decreased significantly (p < 0.05) in stress, nicotine and nicotine + stress groups, compared with control. Serum luteinising hormone decreased (p < 0.05) significantly in stress and nicotine + stress groups, compared with the control. Histology of the testes showed loss of germ cells in numerous seminiferous tubules, and epididymal histology showed decreased sperm density in stress, nicotine and nicotine + stress groups compared with the control. These negative changes were more severe in the nicotine + stress group. Vitamin E ameliorated the negative changes in the above parameters. This may be attributable to its antioxidant property.

Contributory role of adenosine deaminase in metabolic syndrome.

Adenosine deaminase (ADA) is an enzyme of purine metabolism commonly associated with severe combined immunodeficiency disease and believed to modulate bioactivity of insulin. Its contributory role in patients with metabolic syndrome (having features such as obesity, insulin resistance, fasting hyperglycaemia, lipid abnormalities and hypertension) in South Eastern Nigeria was studied. Body mass index (BMI), fasting blood glucose (FBG), Glycated haemoglobin (GHbA1c), total cholesterol, HDL-cholesterol, LDL-cholesterol (usually impaired in metabolic syndrome) and total serum ADA activity were measured in different groups of patients with metabolic syndrome (test subjects) and apparently healthy subjects (controls). The test subjects comprised six subgroups made up of the following; obese diabetic (N=25), obese non-diabetic (N=25), Non-obese diabetic (N=25), patients with hypercholesterolaemia (N=25), LDL-cholesterolaemia (N=25) and HDL-cholesterolaemia (N=25). The results showed that the mean values of all the parameters studied (BMI, FBG, GHbA1c, total cholesterol, HDL-cholesterol and LDL-cholesterol) were higher in the test subjects than their controls. BMI did not correlate significantly with FBG, GHbA1c, and ADA in the test and control subjects respectively. The mean serum ADA activity in the test subjects of obese diabetic, obese non-diabetic and non-obese diabetic subjects was higher than in controls (p< 0.001). ADA activity was also higher in the test subjects of hypercholesterolaemia, HDL-cholesterolaemia and LDL-cholesterolaemia than in control (p< 0.001). ADA activity also correlated positively with hypercholesterolemia (r = 0.640; p<0.001), HDL-cholesterolaemia (r = 0.646; p<0.001) and LDL-cholesterolaemia (r = 0.932; p<0.001), with the highest correlation in the LDL-cholesterolaemia. In conclusion, ADA activity is increased significantly in all parameters of metabolic syndrome studied and showed a significant correlation with all the three groups of dyslipidaemic subjects studied. ADA could therefore be used in daily routine laboratory assessment of most metabolic diseases especially in obese and diabetic patients.

Effect of ethanolic extract of Carpolobia lutea G. Don (polygalaceae) root on learning and memory in CD1 mice.

Carpolobia lutea, commonly called cattle stick or poor man's candle, is used by traditional herbalists in eastern Nigeria to treat 'madness'. It has a reported analgesic and anti-nociceptive effect. The effect of its ethanolic root extract on learning and memory was investigated. Thirty mice were divided into three groups of ten each. One group of mice served as the control and was given normal saline (p.o.) while the other two groups were given acute low dose (1500mg/kg, p.o.) and high dose (2500mg/kg, p.o.) (LD50 3338.83mg/kg). The effect of the extract on cognitive memory was investigated using the Novel Object recognition task (NORT) while the effect on visuospatial learning and memory was studied using the Morris Water maze (MWM). The results obtained in the NORT show that the index of habituation was significantly lower following acute treatment with a low dose of C. lutea extract compared to control. However, the index of habituation did not differ following treatment with a high dose of C. lutea compared to control but it was higher compared to the low dose. Following treatment with a low dose of the extract, the index of discrimination was significantly higher compared to control. The index of discrimination in the high dose treatment group did not differ from control, but it was lower compared to the low dose treatment. This indicated that there was improved cognitive memory only in the low dose treatment group. In the MWM there was no significant difference in swim latency during Acquisition and Reversal training. There also was no significant difference in quadrant duration during probe trial. The swim latency during the visible platform test showed that all mice used had good visual acuity. Therefore, the ethanolic extract of C. lutea root enhanced cognitive memory. However it did not affect visuospatial learning and memory.

Pattern of neurobehaviour in albino rats in the open field following oral artesunate administration.

The neurobehavioural patterns in the open field following oral artesunate administration was studied using 40 albino rats randomly assigned to three Groups, namely A, B and C. Prior to the test, all the animals were acclimatized for 5 minutes in the open field maze. Group A (8 males and 8 females) received therapeutic doses of artesunate (1.42 mg/kg per oral (p.o.)--using oro-gastric tubes while Group B (8 males and 8 females) received pharmacological doses of 4.26 mg/kg (p.o.). Group C served as the control and were administered only distilled water (p.o.). Gross behavioural changes were noted following the therapeutic and pharmacological administration of artesunate for five days. Rats in Groups A and B showed marked decrease in loco motor activity (line crossing) and exploratory (rearing and walling) activities in comparison with the control (P<0.05). The centre square activity was significantly decreased in Groups A and B in comparison with the control (P<0.01). The number of faecal boli and urine puddles did not change significantly in Groups A and B when compared with the control (P>0.05). However, the frequency of grooming was significantly lower in Groups A and B rats than in the control (P<0.01). The frequency and duration of freezing were significantly higher in Groups A and B rats than in the control rats (P<0.01). There were no significant differences between the values for the male and female rats. There was also no dose dependent effect of artesunate on the activities studied. Oral administration of artesunate significantly decreases loco motor and exploratory behaviours in the albino rat.

Prediction formulae for lung function parameters in females of south eastern Nigeria.

This study was carried out to obtain normal lung function values for women in south eastern Nigeria with a view to establishing prediction equations for forced vital capacity (FVC), forced expiratory volume at the first second (FEV(1)) and peak expiratory flow rate (PEFR). Lung function values were measured in 600 apparently healthy Nigerian women aged between 18 and 57 years. FVC and FEV1 were significantly related to height [P < 0.001] and [P < 0.01] respectively) and body weight [P < 0.01], PEFR was also related to age [P < 0.01] and height [P < 0.001]. Prediction equations for the various lung function indices were as follows: FVC = 0.145 + (1.390Ht) - (0.0076age) + (0.0089wt); FEV1 = 0.240 + (1.045Ht) - (0.0055age) + (0.0064wt); PEFR = -38.80 + (210.83Ht) + (1.650age) + (0.252wt). Ht is height in meters, wt. is body weight in kilograms and age is age in years. The ventilatory function indices were directly proportional to weight, height and to age. All the observed or measured lung function indices were not significantly different from their predicted values using the above prediction equations. Therefore, we conclude that lung function indices are influenced by the anthropometric parameters viz: age, body weight and height, and the prediction equations stated for FVC, FEV1 and PEFR for Nigerian women between the ages 18 and 57 years are reliable.

Preliminary studies on effect of chloroquine phosphate on gastric acid secretion in rats.

It is not certain whether chloroquine-induced pruritus is mainly attributable to the liberation of histamine, a powerful gastric acid secretagogue from mast cells, which may not be beneficial in peptic ulceration. Therefore, the aim of this study was to find out whether chloroquine (CQ) can stimulate gastric acid secretion in the rat. Gastric acid output was measured by the continuous perfusion of rats stomachs under anaesthesia with normal saline at the rate of 1ml per minutes. Thirty albino rats were divided into five groups of six rats each. Three groups had intraperitoneal administration of the following; normal saline (1 ml/kg control), CQ (3 microgram/kg; test) and Histamine H2 receptor antagonist, Ranitidine [4 microgram/kg] following CQ administration respectively. The other two groups had subcutaneous administration of histamine (100 microgram/kg) alone and histamine following CQ administration respectively. The basal acid secretion, (4.71+/- +/- 0.05 mMol/10mins) in a group of rats was not significantly increased in comparison with the peak acid output [P < 0.05] following normal saline administration (1 ml; ml/kg; i.p.). Administration of CQ in a second group;significantly increased acid secretion to a peak of 7.2 +/- 1.7 mMol/10mins [P < 0.05]. Ranitidine blocked CQ -induced acid secretion in a third group. Histamine significantly increased acid secretion from control level of 4.85 +/- 0.14 mMol/10mins to 51.67 +/- 5.07 mMol/10mins [P < 0.001] in a fourth group, while CQ administered 2mins after histamine administration significantly increased acid level from 4.72 +/- 0.12 mMol/10mins to peak at 20.63 +/- 3.28 mMol/10mins [P< 0.001] in a fifth group of rats. The peak acid output in the fifth group was significantly lower than that obtained with histamine alone. In conclusion, chloroquine is a weak stimulant of gastric acid secretion rats. It inhibits histamine-stimulated acid secretion probably by occupying histamine H (2) receptors in rats.