Macular hole surgery follow-up with spectral domain-optical coherence tomography-guided facedown posturing.

PURPOSE: The main treatment for macular hole (MH) is pars plana vitrectomy, with or without internal limiting membrane (ILM) peeling, followed by gas tamponade and face-down positioning (FDP). This study aims to present the anatomical and visual outcomes following MH repair with optical coherence tomography (OCT)-guided FDP. METHODS: Thirty-two patients who underwent surgery for idiopathic MH were enrolled. The requirement for the prone position was lifted for those with MH closure observed under gas on postoperative day one OCT. Patients with unclosed MHs were instructed to maintain FDP until the 3rd day. Best-corrected visual acuity at preoperative, postoperative 1st month, and the last visit, closure time post-surgery, duration of prone position, and surgical success rate were recorded. RESULTS: Among the patients, 21 underwent phacovitrectomy + ILM peeling + gas tamponade, while 11 had vitrectomy + ILM peeling + gas tamponade. On postoperative day one, 28 out of 32 MHs closed, with 3 closures on day 3 and one on day 5. There were 18 stage two (56.3%), 13 stage three (40.6%) and 1 stage four (3.1%) MHs. The mean minimum MH diameter was 381.75 ± 68.07 (min 260-max 517) microns. All patients with MH closure time over postoperative day one had non-combined vitrectomy instead of phacovitrectomy. No late complications were observed. CONCLUSIONS: OCT-guided FDP approach yields excellent closure rates with no late complications and ensures good patient comfort.

Choroidal vascularity index changes in different treatments for vitreomacular traction.

INTRODUCTION: The aim of this study was to examine if choroidal vascularity index (CVI) is different in eyes with unilateral vitreomacular traction (VMT) from their healthy fellow eyes; and whether different treatments affect the CVI. METHODS: The baseline and 8-week post treatment CVIs of 56 unilateral VMT patients that underwent spontaneous resolution (n = 30), vitreoretinal surgery (n = 16) or pneumatic vitreolysis (n = 10) were compared with fellow eyes using paired samples t-test. Partial correlation analyses correcting age and gender was used for calculations between treatment groups. P values < 0.05 were considered statistically significant. RESULTS: The mean baseline CVI for VMT and control eyes had no statistically significant difference (p = 0.81, r= -0.38). The post traction release follow-up CVI of VMT eyes and contralateral eyes had no significant difference (p = 0.12, r = 0.49). In spontaneous resolution group, vitreoretinal surgery group and pneumatic vitreolysis group the baseline and follow up CVIs of VMT eyes were statistically similar (p = 0.72, p = 0.32 and p = 0.79 respectively).Spontaneous detachment patients' CVIs showed a 0.57±5.81% increase, vitreoretinal surgery group had a reduction of 1.098±4.76%, and the pneumatic vitreolysis patients showed a CVI reduction of 0.307±4.24%. However, none of these changes was found to be statistically significant when compared between the groups (p = 0.21, r = 0.02). DISCUSSION: Previous studies have argued that vitreomacular traction might have a role on the choroidal changes seen in the vitreoretinal interface disorders. This study has shown that VMT alone does not cause any significant changes in choroidal vascular index pre or post traction release.

Synthesis of New Ester Derivatives of Salicylic Acid and Evaluation of Their COX Inhibitory Potential.

Salicylic acid is an NSAID with serious side effects on the GIS. The side effects of salicylic acid on the GIS are slightly reduced by acetylating salicylic acid. 12 new ester analogs of salicylic acid were synthesized with high yields in this study. The chemical structures of the synthesized compounds were characterized by 1 H-NMR, 13 C-NMR, and HRMS spectra. The inhibitory potential of the compounds was evaluated on COXs by in vitro and in silico studies. The COX2 inhibitory activity of the most potent inhibitor MEST1 (IC50 : 0.048 µM) was found to be much higher than the COX2 inhibitory activity of aspirin (IC50 : 2.60 µM). In docking studies, the strongest inhibitor among the compounds synthesized was predicted to be MEST1, with the lowest binding energy. Docking studies revealed that MEST1 extends from the hydrophobic channel to the top of the cyclooxygenase active site, forming various interactions with residues in the binding pocket.

"Do the Best You Can with Resources You Have to Offer": Community stakeholder views on supporting immigrant families.

First and second-generation immigrant families of young children in the United States face potential challenges that may be mitigated with stakeholder support in their communities. We examined self-reported views and behaviors among professionals (n = 76) working with families in a mid-Atlantic urban community, and whether these views correlated with demographic factors. Over half of respondents were not able/willing to report the number of immigrant families served and over half believed immigrant parents are less likely to advocate for themselves or their child. Participants were fairly split in seeking advice from others and comfort in talking with immigrant families about their culture/needs. It is essential to assess stakeholders' views on perceived roles, roadblocks, and desired supports. This analysis informs efforts to work more collaboratively with community partners to improve outreach to immigrant families during those formative years in a child's development. Implications for research, practice, and policy are discussed.

Choroidal vascularity index changes with phacovitrectomy for vitreoretinal interface disorders.

Purpose: Vitreomacular interface disorders have long been argued to change choroidal structure. The aim of this study was to determine the choroidal vascularity index (CVI) changes following internal limiting membrane peeling for epiretinal membrane (ERM) and full thickness macular hole (FTMH). Methods: Fifty-nine patients with unilateral ERM and 56 with unilateral FTMH were included in the study. Axial length, pre- and post-surgery intraocular pressure, baseline and post-phacovitrectomy CVI were calculated and compared with the normal fellow eyes. To compare the baseline and the final measurements, Wilcoxon test was used. Mann-Whitney U test was used for independent data comparisons. Median and standard deviations were compared. Results: Axial length, pre- and post-surgery intraocular pressure differences were insignificant between study and fellow eyes within all groups. CVI were significantly lower in post-vitrectomy study eyes of all groups compared with pre-surgery (P < 0.001). There were no significant changes before and after the surgeries in fellow eyes. Baseline CVI of ERM study eyes (median 65.90%) and FTHM study eyes (median 65.59%) did not differ significantly between groups (U = 1336, P = 0.07, r = 0.16). Conclusion: There are conflicting results of vitreoretinal interface disorders CVI in the literature. In this study, both FTMH and ERM eyes showed reduced CVI postoperatively compared with the baseline. Preoperatively, there were no difference between study eyes and the fellow eyes.

Effect of eyeliner and mascara use on tear film and meibomian glands.

PURPOSE: This study was conducted to see whether eyeliner, mascara, or combined eyeliner and mascara (EM) use affects tear production, tear film stability, and meibomian gland (MG) loss. METHODS: Two hundred and twenty healthy women underwent noninvasive tear break-up time (NTBUT) measurement, meibography, and Schirmer testing. Study groups were no makeup (NM) group, eyeliner-only group, mascara-only group, and those who used both EM. The one-way analysis of variance test was used for group comparisons. Chi-square test was used for meiboscale comparison. RESULTS: NTBUT (seconds) results were 11.5 ± 4.8 (no makeup), 21.3 ± 69 (eyeliner only), 21.8 ± 6.5 (mascara only), and 22.5 ± 7.0 (eyeliner-mascara). The differences between groups were significant (P < 0.0001). All makeup groups (eyeliner only, mascara only, eyeliner-mascara) had significantly diminished values compared with NM group (P < 0.001, P < 0.001 and P = 0.003, respectively). Schirmer test (millimeters) results were 22.7 ± 6.4 (NM group), 21.3 ± 6.9 (eyeliner only), 21.8 ± 6.5 (mascara only), and 22.5 ± 7.0 (eyeliner-mascara) with no significant differences between groups (P = 0.66). Meiboscale grading revealed that NM group had significantly lower values of MG loss compared with eyeliner-only (EO) (P = 0.01), mascara-only (MO) (P = 0.002), and eyeliner-mascara groups (P = 0.007). There were no significant differences between EO and MO (P = 0.31), EO and eyeliner-mascara (P = 0.39), or MO and eyeliner-mascara groups (P = 0.91). CONCLUSION: None of the makeup groups had changes in Schirmer wetting. All eye cosmetic groups have significant changes of NTBUT and meibography compared with NM subjects, and yet combined use of EM does not affect ocular surface more adversely than their separate use.

Choroidal and Macular Thickness in Eyes with Amblyopia.

OBJECTIVES: This study was performed to assess and analyze the retinal and choroidal thickness in amblyopic eyes using spectral-domain optical coherence tomography and enhanced depth imaging optical coherence tomography. METHODS: A total of 67 children with amblyopia and 31 age- and gender-matched healthy non-amblyopic control subjects were enrolled in the study. The 67 amblyopic children were divided into 3 groups: hypermetropic amblyopia (Group 1). microesotropia (Group 2). and myopic anisometropia (Group 3). All of the participants underwent a detailed ophthalmologic examination and orthoptic assessment. The subfoveal choroidal thickness was measured at 500-. 750-. 1000-. and 15000-micron intervals nasally and temporally. Central macular thickness was also measured in the subfoveal. parafoveal inferior. parafoveal superior. parafoveal nasal. and parafoveal temporal superior. inferior. nasal. and temporal quadrants. All of the parameters of the amblyopic eyes. fellow eyes. and control eyes were compared. RESULTS: In all. 34 female and 33 male patients were studied. The mean age was 8.6±2.8 years (range: 5-12 years). Comparison of the choroidal thickness and macular thickness measurements between the amblyopic and non-amblyopic eye of the same patient within each group revealed no statistically significant differences. Comparison of the findings in the amblyopic eyes of Group 1 and Group 3 with the control group revealed that the choroidal thickness measurements were smaller in the amblyopic eyes in all quadrants. however. only the nasal quadrant measurements demonstrated a statistical significance. The subfoveal macular thickness value was also smaller in both groups when compared with the control eyes. CONCLUSION: Our results indicated that amblyopia. whether anisometropic or microtropic. did not seem to significantly affect choroidal thickness.

Structural Analysis of the Retina and Choroid before and after Carotid Artery Surgery.

Purpose: To evaluate retinal and choroidal changes in patients with internal carotid artery stenosis who had undergone carotid artery stenting or endarterectomy.Methods: The study included 43 patients with internal carotid artery (ICA) stenosis that required stenting or endarterectomy and 40 healthy controls. Patients were divided into two groups according to the degree of stenosis evaluated by magnetic resonance angiography. Group 1 consisted of patients having ICA stenosis of 50 to 70%, and Group 2 has more than 70%. Enhanced depth imaging optical coherence tomography (EDI-OCT) was used to measure the retinal thickness (RT) and choroidal thickness (CT) in all subjects before surgery and at 1, 3, and 6 months after surgery.Results: Subfoveal and parafoveal CT were significantly lower in patients with ICA stenosis than the control group (p < .05, respectively). Patients with 50-70% stenosis had a significant increase in the CT at 1, 3, and 6 months after ICA stenting or endarterectomy (p < .05). Patients with >%70 stenosis did not have a significant increase in the CT at any time after ICA stenting or endarterectomy. Retinal thickness was not statistically different between the patients with ICA stenosis and the control subjects, and RT showed no significant change in patients with ICA stenosis before and after the surgery.Conclusion: Choroidal thickness was significantly thinner in patients with internal carotid artery stenosis. ICA stenting provided a recovery in the choroidal thickness in patients with moderate to advanced stenosis.

Effect of intravitreal and intraperitoneal cyanidin-3-glucoside injection in oxygen-induced retinopathy mouse model.

Purpose: To evaluate the effect of cyanidin-3-glucoside (C3G) in oxygen-induced retinopathy (OIR) mouse model. Methods: In this experimental study, 10 C57BL / 6J type mice exposed to room air comprised two control groups (n = 5 each; a negative control and a group receiving intravitreal sterile dimethyl sulfoxide [IVS DMSO]). Thirty C57BL / 6J type mice exposed to 75% ± 2% oxygen from postnatal day 7 to postnatal day 12 comprised the OIR groups. On postnatal day 12, these mice were randomized into six groups (n = 5 each): two OIR control groups (negative control and IVS DMSO), two intravitreal C3G groups (300 and 600 ng/µL), and two intraperitoneal C3G groups (0.05 and 0.1 mg/kg). We quantified neovascularization by counting endothelial cell proliferation on the vitreal side of the inner limiting membrane of the retina and examined histological and ultrastructural changes via light and electron microscopy and apoptosis by terminal deoxynucleotidyl transferase deoxy-UTP-nick end labeling. Results: The intravitreal C3G groups yielded lower endothelial cell counts compared with the intravitreal DMSO group. The intraperitoneal high-dose group had lower cell counts compared with the OIR control groups. Electron microscopy revealed significantly less mitochondrial dysmorphology in intravitreal groups and the high-dose intraperitoneal mice. We noted no difference in apoptotic cell count between the controls, low-dose intravitreal, and both intraperitoneal groups. However, apoptotic cell count was significantly higher in the high-dose intravitreal group. Conclusion: C3G suppresses endothelial cell proliferation in an OIR mouse model, leads to a reduced hyperoxia-induced mitochondrial dysmorphology, but increases apoptotic cell death in high concentrations.

A diagnostic dilemma in a patient with delayed onset endophthalmitis.

We report a case of nonpainful uveitis nine months after an uncomplicated phacoemulsification cataract surgery. Chronic postoperative endophthalmitis was suspected. Diagnostic vitrectomy and partial capsular bag removal was performed, but the specimens cultured in microbiology laboratory showed no pathogens. Systemic workup came positive for skin Tuberculosis test, and presumed intraocular tuberculosis treatment was started accordingly. Inflammation persisted, so a repeat vitrectomy was performed with removal of the lens implant with the capsule, and this time bedside culture inoculation was performed in operating room, revealing Pseudomonas infection. Delayed-onset postoperative endophthalmitis typically progresses slowly and therefore can be confused with uveitis and treated with steroid and immunosuppressant treatment regimes. Our case confirms both the value of immediate bacterial inoculation and the necessity of aggressive surgical treatment in chronic postoperative endophthalmitis cases.

Refractive outcome comparison between vitreomacular interface disorders after phacovitrectomy.

PURPOSE: To compare the refractive accuracy of intraocular lens (IOL) power calculations between patients with vitreomacular interface disorders who had phacovitrectomy for vitreomacular traction (VMT), epiretinal membranes (ERM), and macular holes. SETTING: Baskent University Department of Ophthalmology, Ankara, Turkey. DESIGN: Retrospective case series. METHODS: Refraction results 8 weeks postoperatively were compared between phacovitrectomy (3 study groups comprising eyes with VMT with intrafoveal pseudocysts, ERM, or medium-to-large macular holes) and phacoemulsification (control group comprising eyes having phacoemulsification only). The IOLMaster 700 partial coherence interferometry (PCI) device and Haigis formula were used for all calculations. RESULTS: This study included 100 eyes (100 patients), 25 in each of the 4 groups. There was no statistically significant difference in axial length (AL) between the groups (P = .305). Differences in the preoperative macular thickness were statistically significant between all groups except between the macular hole and VMT groups. Most eyes (92%) in the VMT and macular hole groups and all eyes in the VMT and phacoemulsification groups achieved a final refraction within ±1.00 diopter of the refractive aim. The mean prediction error and the mean absolute error did not differ significantly between the groups. In all groups, there was no significant correlation between prediction error and age, AL, preoperative refractive error, or preoperative or postoperative macular thickness (P > .05). CONCLUSIONS: The IOL power calculation with PCI yielded no difference in postoperative refraction errors between the vitreomacular interface disorders. There was no correlation with preoperative refraction, age, or preoperative or postoperative macular thickness.

Pseudoduplication of the optic disc in moderate myopia.

We report a case of optic disc pseudoduplication without pathological myopia. A 79-year-old woman presented with gradually decreased vision. Fundus examination showed macular drusen in both eyes and subretinal haemorrhage in the left eye. Both optic discs appeared to be tilted and the left optic disc was seen to be inferiorly duplicated. Pseudodoubling of the optic discs can be caused by optic disc and peripapillary chorioretinal colobomas and pathological myopia. Considering that our patient did not have enough axial length to merit a diagnosis of pathological myopia and no pathological fundus lesions typical of elongated sclera, we suggest that acquired pseudoduplication is not a condition unique to pathological myopia, but can occur in all myopic patients. The clinical materials, including ophthalmological examination, fundus fluorescent angiography and MRI scan of the orbit, were reported, and its pertinent literatures were reviewed.

Abducens Nerve Palsy and Ipsilateral Horner Syndrome in a Patient With Carotid-Cavernous Fistula.

The combination of abducens nerve palsy and ipsilateral Horner syndrome was first described by Parkinson and considered as a localizing sign of posterior cavernous sinus lesions. The authors present a case with right abducens nerve palsy with ipsilateral Horner syndrome in a patient with carotid-cavernous fistula because of head trauma. The patient was referred to the ophthalmology clinic with diplopia complaint after suffering a head trauma during a motorcycle accident. Cerebral angiography showed low-flow carotid-cavernous fistula.

A cannabinoid ligand, anandamide, exacerbates endotoxin-induced uveitis in rabbits.

PURPOSE: This study aimed to investigate the effects of anandamide or arachidonylethanolamide (AEA), an endogenous cannabinoid receptor agonist, on intraocular inflammation in an endotoxin-induced uveitis (EIU) model in rabbits. METHODS: Forty New Zealand albino male rabbits were used (5 groups, 8 animals in each). After establishment of sufficient anesthesia, animals were taken under surgery for intravitreal injections. A maximum amount of 50 µL of solution was injected into the central vitreous with a 30-gauge needle. In the control group, sterile saline was injected into the right eyes of the animals. Likewise, AEA (10(-5) M) in the second group, lipopolysaccharide (LPS; 100 ng) in the third group, and AEA (10(-5) M) and LPS (100 ng) in the fourth group were administered. Fifth group received 0.1 mL subtenon injection of AM251 (10(-5) M), a CB(1)-receptor antagonist, 30 min prior to intravitreal LPS (100 ng) and AEA (10(-5) M) injection. At 24 h after the surgical intervention, clinical evaluation was performed and animals were then euthanized with 100 mg/kg intravenous pentobarbital injections. Immediately after the induction of pentobarbital anesthesia, the anterior chamber of the eyes was quickly punctured using a 30-gauge needle to drain aqueous humor (AH) and obtained specimens were used for cell count, protein measurement, and microbiological contamination tests. After AH collection, enucleation was performed and enucleated material was kept for the pathological evaluation. RESULTS: AEA caused an overall worsening of EIU in studied eyes. It significantly increased the detrimental effects of endotoxin, as assessed by clinical investigation of ocular inflammation, AH leukocyte content, and AH protein concentrations. CB(1)-receptor antagonist AM251 administration reversed some components of this AEA-induced exacerbation to significant extents. CONCLUSION: AEA exacerbated EIU in rabbit eyes. AM251 has been found beneficial to prevent AEA's aggravating impact on EIU. As AEA is a treatment choice for lowering intraocular pressure in ophthalmology practice, concurrent use of CB(1)-receptor antagonists may be a questionable strategy in cases of secondary glaucoma, to avoid aggravation of the present inflammation.

Enhancement effects of nicotine on neurogenic relaxation responses in the corpus cavernosum in rabbits: the role of nicotinic acetylcholine receptor subtypes.

Nicotine acts as an agonist of nicotinic acetylcholine receptors, which belong to a superfamily of neurotransmitter-gated ion channels. We previously demonstrated that nicotine increases the electrical field stimulation (EFS)-evoked nitrergic relaxation responses via activation of nicotinic acetylcholine receptors. The aim of the present study is to investigate the subtypes of nicotinic acetylcholine receptors in rabbit corpus cavernosum. EFS-evoked relaxation responses were recorded from corpus cavernosum strips obtained from rabbits with an isometric force displacement transducers. Effects of nicotine on EFS-evoked relaxations were examined in pre-contracted tissues. Then the effect of nicotine on the EFS-evoked relaxations was examined in the presence of hexamethonium, dihydro-beta-erythroidine, mecamylamine or alpha-bungarotoxin. In our study, nicotine (3 x 10(-5), 10(-4)) transiently increased nitrergic relaxations induced by EFS in the rabbit isolated corpus cavernosum. While hexamethonium and mecamylamine near totally inhibited or abolished the neurorelaxation response to nicotine (3 x 10(-5)) on EFS, dihydro-beta-erythroidine and alpha-bungarotoxin partially inhibited these responses. These findings demonstrated that the alpha3-beta4, alpha4-beta2 and alpha7 subunits of nicotinic acetylcholine receptors play role on the nicotine-induced augmentation in EFS-evoked relaxation responses in rabbit corpus cavernosum.

Role of nicotinic acetylcholine receptor subtypes on nicotine-induced neurogenic contractile response alternation in the rabbit gastric fundus.

Nicotine is a nonspecific agonist of nicotinic acetylcholine receptors. We previously demonstrated that nicotine increases the electrical field stimulation (EFS)-evoked contractile responses possibly by facilitating neurotransmitters release from nerve terminals by a mechanism dependent on the influx of Ca(2+) from voltage gated Ca(2+) channels via activation of nicotinic acetylcholine receptor. The aim of this study is to investigate subtypes of presynaptic nicotinic acetylcholine receptors involved in nicotine induced EFS-evoked contractile response alternation in the rabbit gastric fundus. EFS-evoked contractile responses were recorded from gastric fundus strips obtained from rabbits with isometric force displacement transducers. Effects of nicotine on EFS evoked contractions were examined. Then the effect of nicotine on the EFS-evoked contractions was examined in the presence of hexamethonium, dihydro-beta-erythroidine, mecamylamine or alpha-bungarotoxin. In our study, nicotine (10(-4), 3x10(-4) M) transiently increased neurogenic contraction induced by EFS in the rabbit isolated gastric fundus. While hexamethonium, dihydro-beta-erythroidine and mecamylamine inhibited the neurocontractile response to nicotine on EFS, alpha-bungarotoxin did not alter these responses. The pA(2) values of the antagonists were 4.67 (hexamethonium, n=8), 5.33 (dihydro-beta-erythroidine, n=8) and 5.43 (mecamylamine, n=8). These findings showed that the alpha3beta4 and alpha4beta2 subunits of nicotinic acetylcholine receptors play a role on the nicotine-induced augmentation in EFS-evoked contractile responses in rabbit gastric fundus.

Hydrogen peroxide and antioxidizing enzymes involved in modulation of transient facilitatory effects of nicotine on neurogenic contractile responses in rat gastric fundus.

Nicotine acts as an agonist of nicotinic acetylcholine receptors. Nicotinic acetylcholine receptors play a role in the modulation of neurotransmitter release in both the central and the peripheral nervous system. Moderate reactive oxygen species levels modulate the regulation of physiological functions e.g. neurotransmitter release. Previously in rabbit gastric fundus we demonstrated that nicotine transiently increased neurogenic contraction induced by electrical field stimulation (EFS). In this study we aimed to investigate the effects of hydrogen peroxide (H2O2), antioxidizing enzymes catalase and superoxide dismutase (SOD) on nicotine induced increases at cholinergic neurotransmission in rabbit gastric fundus. Although H2O2 did not alter nicotine induced transient neurogenic contractions at concentrations of 10(-6) and 10(-5) M, at high concentration (10(-4) M) H2O2 inhibited nicotine induced increases. Catalase (500 units/ml), enhanced the effect of nicotine but did not alter nicotine induced transient neurogenic contractions at the concentrations of 100 and 250 units/ml. SOD (75,150 and 225 units/ml) did not alter nicotine induced transient neurogenic contractions. In conclusion, at high concentration H2O2 (10(-4) M) inhibited nicotine's transient ability to augment neurogenic contractions and catalase (500 units/ml) enhanced the effect of nicotine.

Nicotine potentiates the electrical field stimulation-evoked contraction of non-pregnant rabbit myometrium.

The women who smoke have lower fertility rates which might be due to harmful effects of nicotine on tubal function and menstrual cycle. Although the uterine contractility of the non-pregnant uterus plays an important role in the human reproduction process, the influence of nicotine on the contractile responses in uterus is not known. Nicotine increases the release of neurotransmitters following nerve stimulation both in the central and peripheral nervous system through acting on nicotinic acetylcholine receptors (nAchRs). The aim of this study was to examine whether the electrical field stimulation (EFS)-evoked contraction is altered in rabbit myometrium strips in the presence of nicotine to evaluate the changes in contractility. EFS-evoked contractile responses were recorded from myometrium strips obtained from non-pregnant rabbits in the absence and presence of nicotine. Nicotine led to the increase in the amplitudes of the EFS-evoked contractile responses in a dose-dependent manner. Therefore, the effects of hexamethonium, cadmium, indomethacin, atropine, and N(omega)-Nitro-L-arginine methyl ester hydrochloride were tested on the EFS-evoked contractions in the absence or presence of nicotine to clarify the mechanisms of nicotine-induced potentiation in EFS-evoked contractile responses. Indomethacin, a non-selective cyclooxygenase inhibitor, and hexamethonium, a ganglionic blocker, inhibited nicotine-induced increase in EFS-evoked responses, whereas other chemicals produced no effect. These results suggest that nicotine-induced potentiation may be mediated by nAchRs and prostaglandins. In conclusion, failure of quiescence in the uterus due to increased contractility by nicotine might be one of the factors contributing to infertility in female smokers.

Nicotine potentiates the neurogenic contractile response of rabbit bladder tissue via nicotinic acetylcholine receptors: nitric oxide and prostaglandins have no role in this process.

Nicotine, a nicotinic acetylcholine receptors (nAChRs) agonist, has a role in modulation of the neurotransmitter release following nerve stimulation in both the central and peripheral nervous systems. The aim of this study was to determine whether electrical field stimulation (EFS)-evoked contractions are altered in rabbit bladder in the presence of nicotine and, if an alteration occurs, to investigate the effects of nitric oxide and prostaglandins on nicotine-induced alternation in isolated rabbit bladder. EFS-evoked contractile responses from rabbit bladder obtained were recorded with isometric force displacement transducers. Nicotine was added to preparations at various concentrations. The effects of hexamethonium, cadmium (Cd(2+)), indomethacin and N-nitro-L-arginine methyl ester (L-NAME) were tested on the EFS-evoked contractions in the presence of nicotine. Nicotine led to a dose-dependent increase in the amplitude of the EFS-evoked contractile responses. Cd(2+) and hexamethonium inhibited the nicotine-induced increase in EFS-evoked responses, whereas indomethacin and L-NAME had no effect. In conclusion, nicotine increased the EFS-evoked contractile responses possibly by facilitating release of neurotransmitters from nerve terminals by a mechanism dependent on the influx of Ca(2+) from voltage-gated Ca(2+) channels (VGCCs) via activation of nAChRs in isolated rabbit bladder. Nitric oxide and prostaglandins do not have a physiological role in the regulation of neurotransmitter release.