Francis V. Udoh

Effects of extracts of seed and leaf of Piper guineense on skeletal muscle activity in rat and frog

The pharmacological effects of leaf and seed extracts of Piper guineense were investigated on phrenic nerve hemidiaphragm activity following electrical stimulation in vitro. Copyright

Activity of alkaloid extract of Carica papaya seeds on reproductive functions in male wistar rats

ABSTRACT Activity of the alkaloid extract of Carica papaya. Linn seed on male reproductive physiology was investigated. Male rats were divided into two groups. Each group of 20 male rats was further divided into 4 subgroups of 5 rats. Each rat was treated with C. papaya. seed extract (10, 50, and 150 mg kg−1day−1) daily for 3 days for fecundity study, semen analysis, and testis histopathology, respectively. Twenty male rats treated with C. papaya. seed extract (10, 50, and 150 mg kg−1 day−1), abstained from sex for 7 days and divided into 4 groups, were mated with fertile female rats: another set of 30 male rats, divided into 4 groups, treated with the seed extract (10, 50, and 150 mg kg−1 day−1), respectively, was used for semen analysis and testis histopathology. The results showed that oral administration of C. papaya. seed extract prevented ovum fertilization, reduced sperm cell counts, revealed sperm cell degeneration, and induced testicular cell lesion. These observations led to the conclusion that C. papaya. seed extract oral administration could induce reversible male infertility and therefore could be used for pharmaceutical development of a male contraceptive.

Hepatotoxicity of the Methanol Extract of Carica papaya. (Paw-Paw) Seeds in Wistar Rats

Abstract Activity of Carica papaya. Linn. (commonly known as paw-paw.) seed extract in liver physiology of albino (Wistar) rats was studied. The MeOH extract of C. papaya. seeds were Soxhlet extracted. Tolerated doses of C. papaya. were estimated in acute toxicity studies and administered orally, single or repeated doses, for 30 days to adult male rats weighing between 190 and 200 g, which were divided into four groups of five rats per group. Group 1 received 10 mg/kg; group 2 received 50 mg/kg; group 3 received 200 mg/kg; group 4 received normal saline (1 ml/rat) as control. Twenty-four hours after treatments, the animals of all groups were sacrificed and blood samples collected by heart puncture into centrifugal tubes. The blood samples were allowed to coagulate before centrifuged at 400 rpm at 4°C for 15 min to separate the serum for enzyme assays. A portion of liver was cut off and fixed in 10% normal saline. The result showed that C. papaya. seed extract treatments caused elevation of rat serum levels of acid phosphatase (ACP), alkaline phosphatase (ALP), and aspartate amino transferase (AST). Also revealed was mild to severe metaplasia of hepatocytes in a dose-related manner as well as proliferation of Kupfer cells and hepatic cells cirrhosis. These biochemical and pathological changes indicated liver cell damage and malfunction. These results, therefore, suggest that seeds of C. papaya. should be used in herbal medicine with care to avoid toxicity.

Uterine muscle reactivity to repeated administration and phytochemistry of the leaf and seed extracts of Piper guineense

The leaf and seed of Piper guineense were separately extracted and the effects of repeated treatments on rat uterine contractions and their chemical composition were investigated. Repeated treatments with the extracts enhanced spontaneous uterine muscle contractions in a dose related pattern for up to 14 days which was followed by a marked decrease in uterine response in those treated for 30 days. Similarly, the pretreatment with the extracts maximally enhanced oxytocin induced uterine contraction in those rats treated for 3 days, this was followed by a gradual reversal of the effect when treatment was repeated for up to 14 days. This enhanced uterine contraction was inhibited following treatment for 30 days.

Influence of Nauclea latifolia Leaf Extracts on Some Hepatic Enzymes of Rats Fed on Coconut Oil and Non-Coconut Oil Meals

Abstract This work focuses primarily on the comparative response of rat liver enzymes to oral administration of the water-soluble fraction of 95% ethanol extract of Nauclea latifolia. Sm. (Rubiaceae) leaves with 10% coconut oil meal and normal rat chow fed for 8 weeks. Forty-eight mature male albino rats of the Wistar strain weighing between 200 and 230 g were divided into two experimental groups. In experiment 1, group 1 (n = 6) was fed normal rat chow for 8 weeks, and groups 2, 3, and 4 (n = 6) were on normal rat chow for 8 weeks before treatment with 170, 340, and 510 mg/kg body weight, respectively, of oral dose of the water-soluble fraction of the ethanol extract of N. latifolia. leaves. In experiment 2, group 1 (n = 6) was fed the 10% coconut oil meal as the experimental control, and groups 2, 3, and 4 (n = 6) were fed the 10% coconut oil meal for 8 weeks before commencing treatment for 2 weeks with the extract of N. latifolia. leaves. The effects of the N. latifolia. leaf extract on some marker enzymes were analyzed. There was a significant increase (p < 0.05) of aspartate aminotransferase (AST) activity in all the groups when compared to the control, but the increase was higher in the 10% coconut oil meal fed groups. Alanine aminotransferase (ALT) activity decreased significantly (p > 0.05) in experiment 1 animals when compared with control. Increase in ALT activity was however observed in experiment 2 (p < 0.05). Alkaline phosphatase (ALP) and lactate dehydrogenase (LDH) activities did not change in both experiments. There was no significant (p > 0.05) change in γ-GT activity in experiment 1, but in experiment 2 glutamyl transferase (GGT) decreased in the water-soluble fraction of the ethanol extract. N. latifolia. leaf extract is capable of reducing the activity of γ-GT if raised by other factors. We also concluded that feeding animals with 10% coconut oil meal predisposes them to more adverse effects by the extract of N. latifolia. leaves.

Effects of Daniellia oliveri stem bark and leaf extracts on rat skeletal muscle

The stem bark and leaves of Daniellia oliveri were screened phytochemically and the effects of their respective methanol extracts on the skeletal muscle of rats were investigated using the isolated phrenic nerve hemidiaphragm muscle preparation. Both were found to contain tannins, cardiac and saponin glycosides. In addition, the bark, but not leaves, contained cyanogenetic glycosides. The methanol extracts were found to possess neuromuscular blocking properties. The leaf extract appeared to act primarily by inhibiting the influx of extracellular Ca2+ principally by inhibiting K+ channels. The inhibitory action of the bark extract appeared to be mediated by interference with transmitter release and an action on multiple sites. Copyright

Effect of Extract of Leaf and Seed of Piper guineense on Some Smooth Muscle Activity in Rat, Guinea-pig and Rabbit

Extracts of the leaf and seed of Piper guineense were separately prepared and their pharmacological effects screened using smooth muscle of the gastrointestinal tract and uterus. The leaf extract enhanced both the frequency and tone of spontaneous contractions of rabbit jejunum and induced contraction of guinea‐pig ileum, which were blocked by atropine. The seed extract had the opposite effect on rabbit jejunum, an inhibition which was antagonized by prazocin, and little or no effect on guinea‐pig ileum. Both extracts had a stimulant effect on rat uterine muscle, the seed extract to a lesser extent.

Changes in smooth muscle sensitivity to agonist drugs during development

The receptors in the expansor secundariorum muscle of chicks were characterized pharmacologically and the changes in their response to nerve stimulation and agonist drugs determined during development. The muscle responded to noradrenergic nerve stimulation, noradrenaline and 5-hydroxytryptamine without any change in sensitivity during development. Expansor muscles from 15-day-old chicks were more sensitive to isoprenaline than muscles from older animals. The muscle from 15-day-old chicks responded to acetylcholine and histamine; the sensitivity to both drugs decreased progressively with increasing age of the chicks and disappeared by day 40 posthatching. The normal developmental decrease in response to acetylcholine and histamine were prevented by surgical denervation of the muscle; an intervention that also induced supersensitivity to noradrenaline greater than isoprenaline greater than 5-hydroxytryptamine. The muscle responded to potassium chloride without any change in sensitivity during development or following surgical denervation. These findings indicate that sympathetic nerves influence the responsiveness of the expansor secundariorum muscle to drugs, especially the development decrease in response to acetylcholine and histamine.

Dynamic Activity of the Ethanolic and Water Extracts of the Leaf of Gnetum africanum, Repeated Treatment on Uterine Muscle Morphology of Rats

Objective To investigate the effect of ethanolic and water extracts of the leaves of Gnetum africanum on the morphology of uterine smooth muscles of rats. Methods Three tolerated doses of the extracts, 10 mg/kg, 200 mg/kg and 700 mg/kg per day, were obtained from the results of acute toxicity test and administered orally to three respective groups of female rats for 3 d and saline group of rats served as the negative control (0 mg/ml), 17β-estradiol group of rats served as the positive group, 5 rats per group. Rats from each of the groups were sacrificed on the 4th day and their uteri were carefully isolated and examined. Results The study revealed that both extracts of the leaves of Gnetum africanum influenced the uterine muscle weight and growth of both adult and immature female rats in a similar manner as 17β-estradiol. Conclusion The leaves of Gnetum africanum may be phytoestrogenic and could influence fetal implantation or ova fertilization, therefore, abuse in the use of the leaves of Gnetum africanum as vegetable in some Nigerian meal. Meanwhile this effect is reversible, the plant-extracts could be possibly developed as a female contraceptive to control birth rate.

Effects of stem bark and leaf extracts of Bridelia ferruginea on rat bladder smooth muscle.

The effects of ethanol extracts of Bridelia ferruginea leaves and stem bark on purinergic neurotransmission in the rat bladder were investigated. The stem bark extract potentiated the contraction of the bladder evoked by exogenous adenosine 5-triphosphate (ATP) but depressed KCl-induced contractions in a dose-related pattern; these two opposite actions might account for the lack of effect on field stimulation of the bladder purinergic nerves. The leaf extract depressed purinergic nerve-mediated contraction of the rat bladder in a dose-related fashion. This action could be attributed to blockade of purinergic neurotransmission since the leaf extract did not affect KCl-induced contractions.