The aim of this study was to investigate the effects of pomegranate (Punica granatum L., Punicaceae) seed extract on uterine contractility. Pomegranate seeds were methanolic extracted and their constituents analyzed using gas chromatography and mass spectrometry. Isometric force was measured in strips of longitudinal rat myometrium and the effects of pomegranate seed extract studied. We found beta-sitosterol to be the main constituent of the extract (16%) and its effects were also investigated. Pomegranate seed extract and beta-sitosterol increased spontaneous contractions in a concentration-dependent manner with a maximum effect at 250 mg/100 mL and 1 mg/100 mL, respectively. The amplitude and frequency of the phasic contraction were significantly increased along with basal tension. The effects of pomegranate seed extract were very similar to those of beta-sitosterol. Force produced in the presence of pomegranate seed extract was abolished by the inhibition of L-type calcium channels or myosin light chain kinase (MLCK). Contractions were not potentiated by pomegranate extract following the inhibition of K channels or inhibition of the sarcoplasmic reticulum calcium ATPase (SERCA). The actions of beta-sitosterol and the extract were not blocked by the estrogen receptor blocker, fulvestrant. We conclude that pomegranate seed extract is a potent stimulator of phasic activity in rat uterus. Our data suggest that the uterotonic effect is due to nonestrogenic effects of beta-sitosterol acting to inhibit K channels and SERCA and thereby increasing contraction via calcium entry on L-type calcium channels and MLCK. We suggest that pomegranate extract and beta-sitosterol may be a useful uterine stimulant.

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The reduction of spermatozoa survival time is a major problem of canine chilled sperm for artificial insemination. The aim of the study was to improve the quality of canine chilled sperm during storage time. We therefore, evaluated the effects of eight treatments with different levels of soybean lecithin concentration (1, 3 and 5%) and egg yolk (20%) in Tris‐citric‐fructose or Tris‐citric‐fructose‐mineral salts extender on chilled canine sperm quality during 10 days of storage. The sperm motility was analysed by computer‐assisted sperm analysis (CASA), whereas plasma membrane integrity, acrosome membrane integrity and mitochondrial membrane potential parameters were determined using a fluorescent staining combination of propidium iodide (PI), Hoechst 33342 (H342), fluorescein isothiocyanate‐conjugated Pisum sativum agglutinin (FITC‐PSA) and 5,5′,6,6′‐tetrachloro‐1,1′,3,3′‐tetraethylbenzimidazolyl‐carbocyanine iodide (JC‐1) by confocal laser scanning microscope. The results showed that egg yolk was found to be better than soybean lecithin in Tris‐citric‐fructose or Tris‐citric‐fructose‐mineral salts extender for maintaining the quality of chilled canine sperm within 10 days of storage (P < 0.05). Although egg yolk in Tris‐citric‐fructose extender could maintain the motility better than other extenders, egg yolk in Tris‐citric‐fructose‐mineral salts extender was the highest in intact plasma membrane, intact acrosome membrane and high mitochondrial membrane potential (P < 0.05). In contrast, the sperm quality of soybean lecithin in Tris‐citric‐fructose‐mineral salts extender was lower than that of soybean lecithin in Tris‐citric‐fructose extender, and soybean lecithin 1% was greater than soybean lecithin 3% and 5% in plasma membrane integrity, acrosome membrane integrity and mitochondrial membrane potential (P < 0.05). In conclusion, soybean lecithin cannot replace egg yolk in Tris‐citric‐fructose or Tris‐citric‐fructose‐mineral salts extenders, and egg yolk in Tris‐citric‐fructose‐mineral salts extender is superior to other extenders in chilling canine sperm.

The aim of this study was to investigate the effects of wild ginger (Costus speciosus (Koen) Smith, Costaceae) rhizome extract on uterine contractility. We particularly examined the effects on spontaneous phasic contractions and the mechanisms whereby it exerts its effects. Wild ginger rhizomes were ethanolic extracted and their constituents analyzed. Isometric force was measured in strips of longitudinal myometrium and the effects of the extract studied. The extract (10 mg/100 mL) increased spontaneous contractions. The amplitude and frequency of the phasic contraction were significantly increased along with basal tension. Force produced in the presence of the extract was abolished by inhibition of l-type calcium channels or myosin light chain kinase (MLCK). The actions of the extract were not blocked by the estrogen receptor blocker, fulvestrant. Although significant amounts of diosgenin were present in the extract, we found that, depending upon its concentration, diosgenin had either no effect or was inhibitory on force. Interestingly, the extract induced significant amounts of force in the absence of extracellular calcium, which could be blocked by inhibition of the sarcoplasmic reticulum calcium-ATPase (SERCA), but not fulvestrant. We conclude that wild ginger rhizome extract stimulates phasic activity in rat uterus. Our data suggest that the uterotonic effect is due to nonestrogenic effects and not those of diosgenin. Wild ginger was able to increase contraction via calcium entry on l-type calcium channels and sarcoplasmic reticulum (SR) calcium release. We suggest that wild ginger rhizome extract may be a useful uterine stimulant.

This study investigated the effects of the co-supplementation of vitamins C (0, 500, and 1000 mg kg À1 ) and E (0, 62.5, and 125 mg kg À1 ) on the growth performance, haematology and the modulation of blood stress indicators and immune parameters in hybrid catfish (Clarias macrocephalus 9 Clarias gariepinus) under combinations of thermal and acidic stress. Supplementation of vitamins C and E influenced the growth, haematological indices, serum chloride, plasma protein and immune parameters (lysozyme, total immunoglobulin and alternative complement haemolytic assay) (P < 0.05). Although vitamins C and E did not prevent a significant reduction in serum chloride, they minimized not only the modulation of blood glucose and plasma protein, but also the reduction in immune parameters (P < 0.05) owing to stress. Our results demonstrated that co-supplementation of 500 mg kg À1 vitamin C and 125 mg kg À1 vitamin E, or 1000 mg kg À1 vitamin C alone, for four weeks and co-supplementation of both vitamins at low levels (vitamins C at 500 mg kg À1 and E at 62.5 mg kg À1 ) for eight weeks had beneficial effects on the growth, amelioration of stress-mediated adverse changes in the physiological and immunosuppressive responses of hybrid catfish under stressful conditions.