The use of a prostacyclin analog, iloprost, as an adjunct to uterus preservation with histidine-tryptophan-ketoglutarate solution.

INTRODUCTION: Although assisted reproductive techniques have made most causes of both male and female infertility treatable, uterine factor infertility is not able to therapy. Therefore, transplantation of the uterus has been suggested as a future possible cure. Organ preservation solutions seek to reduce reperfusion injury. Since iloprost is an antioxidant with cytoprotective properties, we investigated its potential positive effects in histidine-tryptophan-ketoglutarate (HTK) solution after 4 or 24 h cold storage period of the rat uterus. METHODS: We divided 24 female Wistar-albino rats into four groups: Group 1 had the uterus tissue stored in HTK solution at 4 °C for 4h. Group 2, the tissue was stored in HTK solution combined with iloprost (10(-8) M) for 4h at 4 °C. The same procedures were repeated for 24 h for Groups 3 and 4 respectively. Tissue levels of malondialdehyde (MDA) and nitric oxide (NO), as indicators of oxidative stress were determined with histopathological evaluations. RESULTS: MDA and NO levels were compared between the group 1 vs 3; and 2 vs 4. No significant difference was observed between the groups. Cold storage for 24 h produced alterations in histological appearances that were mitigated by the addition of iloprost to HTK solution. CONCLUSION: In conclusion, addition of iloprost to HTK solution reversed the histological alterations after 24h-cold storage of the rat uterus.

Effects of varicocele on electrical field stimulation-induced biphasic twitch responses in the ipsilateral and contralateral rat vasa deferentia.

AIM: Although little is known about the mechanisms, varicocele is considered as one of the factors leading to male infertility. Since reduced motility of the vas deferens was shown to contribute to male infertility, in this study we aimed to investigate the effect of varicocele on electrical field stimulation (EFS)-induced biphasic contractions of the vas deferens in order to evaluate the effect of varicocele on the motility of the vas deferens. MATERIAL AND METHODS: A total of 26 Sprague-Dawley rats (200-250 g) were assigned randomly into two groups: sham (n = 10) and varicocele (n = 16). Varicocele was produced by partial obstruction of the left renal vein. Four weeks after the surgical procedure, vasa deferentia were harvested and EFS-induced responses were recorded from the strips prepared from ipsilateral and contralateral sides via Grass isometric force displacement transducers. Exogenous alpha-beta methyl ATP was applied at the concentration of 10(-5)M to the vasa deferentia strips, and exogenous noradrenalin was applied cumulatively at the concentrations between 10(-7) and 10(-4)M. At the end of each experiment, 80 mM KCl was applied to induce contractions. All contractions were expressed as the percentage of the 80 mM KCl-induced contractions. RESULTS: Varicocele significantly inhibited both phases of EFS-induced biphasic contractions in the ipsilateral side, whereas in the contralateral site it did not produce any change. However, there was no change in exogenously applied alpha-beta methyl ATP, noradrenalin and KCl-evoked contractions of the vasa deferentia obtained from both sides. CONCLUSIONS: These results suggest that varicocele affects the ipsilateral vas deferens motility by reducing neurotransmitter release.

The pharmacokinetics and effects of diltiazem in rabbits.

PURPOSE: To investigate the effect of diltiazem on wound healing after the creation of conjunctival flaps in rabbit eyes. Also, to investigate the pharmacokinetics of diltiazem in rabbits after subconjunctival and topical administration. METHODS: For the histopathological study, a limbal-based flap was prepared and diltiazem was injected subconjunctivally for five days after the surgery. The rabbits were euthanised 20 days after surgery. The effectiveness of diltiazem on wound healing was evaluated by histopathological examination and measurement of the thickness of subconjunctival fibrous tissue. For the pharmacokinetic study, diltiazem was applied topically or injected subconjunctivally. Aqueous paracenteses were performed 0.5, 1, 2, 4 hours thereafter. RESULTS: The histopathological study found no difference in thickness of the subconjunctival fibrous tissue in control and diltiazem-treated eyes. No significant toxicity was observed in eyes treated with diltiazem. The peak aqueous concentration was 3.8 +/- 0.4 microg/ml after topical application and 15.3 +/- 1.1 microg/ml after subconjunctival injection. The peak aqueous concentration was achieved 1/2 hours after administration in both cases. CONCLUSIONS: Diltiazem did not appear to affect wound healing at the dose tested. Topical and subconjunctival diltiazem successfully penetrated the aqueous humor of rabbit eyes.

Decreased (45)Ca(2)(+) uptake in P/Q-type calcium channels in homozygous lethargic (Cacnb4lh) mice is associated with increased beta3 and decreased beta4 calcium channel subunit mRNA expression.

The mutated gene in the lethargic (Cacnb4lh) mouse model of absence seizures encodes the beta4 subunit of voltage-gated calcium channels (VGCCs), leading to decreased mRNA expression of a beta4 subunit that is truncated and cannot bind to alpha1 subunits of VGCCs. In this study we accomplished two goals. First, we studied the functional consequence of altered VGCCs by examining the effects of a selective P/Q-type channel antagonist on KCl-induced (45)Ca(2)(+) uptake in brain synaptosomes from Cacnb4lh homozygotes and non-epileptic controls (designated by +/+). We found that depolarization-induced (45)Ca(2)(+) uptake was significantly reduced in the brains of Cacnb4lh homozygotes, and that the reduced uptake was completely accounted for by reduced function of P/Q-type calcium channel. Second, we examined VGCC subunit composition to determine if other subunits were altered in addition to the mutation affecting beta4 subunits in Cacnb4lh homozygotes; when alterations were found, we determined if they were regional or global. We used in situ hybridization histochemistry (ISHH) to analyze the neuro-anatomic distribution of beta4, beta1b, beta2, beta3, alpha1A, alpha1B, alpha1C, alpha1E, and alpha1G subunit mRNAs in brain sections from matched Cacnb4lh homozygotes and +/+ controls. Our results indicated that expression of beta4 subunit mRNA is globally reduced throughout the brains of Cacnb4lh homozygotes, in contrast to a small but significant global increase in the expression of beta3 subunit mRNA. There were no significant differences in expression of the other VGCC subunit mRNAs examined. Together, these findings indicate that a host of changes in VGCC subunit composition accompany reduced function of P/Q-type channels in homozygous lethargic mice.

Glycine is required for NMDA receptor activation: electrophysiological evidence from intact rat hippocampus.

Fimbrial/commissural stimulation evokes a prolonged negative field potential in stratum radiatum of CA1 region of the rat hippocampus, in situ, upon activation of N-methyl-D-aspartate (NMDA) receptors. This activity can be induced by iontophoresis of NMDLA (50 nA) or glycine (50-100 nA) during low-frequency stimulation. 7-Cl-Kynurenate (10-30 nA) fully antagonized the NMDA receptor-mediated negative wave induced not only by glycine (N = 3) but also by NMDLA (N = 9), suggesting that activation of NMDA receptors is not possible without glycine binding. 7-Cl-Kynurenate also depressed the extracellular negative d.c. potential shifts appearing during iontophoresis of NMDLA. Stimulation with brief, high-frequency trains evoked a negative wave of 2.1 +/- 0.2 mV and 176 +/- 4 ms (N = 20) on the hippocampal field response following the last stimulus. Ketamine (100-200 nA, N = 6) and MK-801 (50-200 nA, N = 7) blocked the negative wave by 74 +/- 13 and 62 +/- 8%, respectively, while glycine (100 nA) potentiated it by 35 +/- 2% (N = 6), indicating that it had a component mediated by NMDA receptors. 7-Cl-Kynurenate (100 nA) antagonized this activity at a comparable rate to the NMDA receptor antagonists (67 +/- 8%, N = 4). A similar negative wave of 0.9 +/- 0.2 mV and 41 +/- 3 ms (N = 12) was evoked in hippocampal slices by high-frequency orthodromic stimulation. Potentiation of this activity upon lowering Mg2+ in ACSF from 1.3 to 0.5 mM further supported that it had an NMDA-mediated component.(ABSTRACT TRUNCATED AT 250 WORDS)