Topiramate-associated acute glaucoma in a migraine patient receiving concomitant citalopram therapy: a case-report

We describe the case of a 34 year-old man with diagnosis of migraine with and without aura that developed myopia and acute glaucoma after 7 days of treatment with topiramate. The patient had also been taking citalopram daily for two months. Both topiramate and citalopram have been related to the increase of intraocular pressure and the development of glaucoma. We can't exclude that in this patient citalopram caused an increase of the ocular pressure in dose-dependent manner, facilitating topiramate-induced glaucoma. We recommend to pay particular attention in prescribing of topiramate in migraine patients who are already under treatment with citalopram or other antidepressants with a similar mechanisms of action

The effects of thymoxamine on guinea pig ileum contractions

The effects of thymoxamine on the contractions induced in guinea pig isolated ileum were examined. The drug was tested in a large range of concentrations (10-8-10-4 M). The twitch response induced by acetylcholine was potentiated by low concentrations and inhibited by high concentrations of the α-blocking drug thymoxamine. The contractions in response to carbachol were always inhibited. Thymoxamine also affected the responses of the ileum to other stimulants: angiotensin, pentagastrin, cholecystokinin. The drug (8 x 10-5, 5 x 10-4 M) inhibited the calcium contraction of high K+ depolarized preparation

EFFETTI STIMOLANTI DA DANTROLENE SODICO SU ORGANI E MUSCOLATURA LISCIA.

The effects of sodium dantrolene (DaNa), a calcium antagonist specifically acting on skeletal muscles, were evaluated on the spontaneous contractions of ileum, uterine horns and longitudinal strips of esophageal smooth muscle, in vitro. DaNa (1.81 to 15 μg/ml) caused a reversible dose-related increase of the spontaneous contractions of the three organs. DaNa (15 μg/ml) caused a 60±3% increase of the ileum spontaneous tone, and caused a 57±3% increase in the frequency of the spontaneous contractions of the uterus. The stimulatory effect of DaNa on the uterine musculature was not antagonized by atropine, methysergide or indomethacin. In the esophagus the maximum increase of the spontaneous tone and contractions (65±2%) was due to 3.7 μg/ml perfusion of DaNa. This effect was antagonized by nifedipin

Specific binding of nicergoline on alpha1-like adrenoreceptor in the rat retina

Systemic treatment with nicergoline, an ergoline derivative showing al-antagonist properties, causes vasodilatation in the eye without apparent untoward cardiovascular effects. In the present work we investigated the ability of nicergoline to inhibit the binding of radiolabelled prazosin in the rat retina and cortex. We found that nicergoline inhibited [H-3]prazosin binding in both tissues, being more potent than unlabelled prazosin in the retinal tissue. The competition curves of the ergoline derivative were well fitted by a one-site model in the cortical tissue, with an IC50 (concentration of the drugs needed to inhibit the binding of labelled prazosin by 50%) of 2.54 x 10(-8)M, and by a two-site model in the retinal tissue, with IC50 values of 7.08 x 10(-12) M and 1.82 x 10(-5)M. 2-(2,6 dimetoxyphenoxyethyl) aminomethyl-1,4-benzodioxane hydrochloride (WB4101) and phentolamine, selective ligands for the high-affinity binding site for prazosin, in particular the alpha(1A)-site, fully inhibited prazosin binding in the cortex but only partially inhibited prazosin binding in the retina, being less potent in this tissue than either nicergoline or prazosin. Our results suggest that a binding component of alpha(1)-adrenoreceptors is expressed to a lesser extent in the retina than the cortex, leading to a reduced response of the retinal tissue to prazosin, and more particularly to WB4101 and phentolamine. The selective binding of the nicergoline on this retinal adrenoreceptor may explain the peculiar efficacy of the drug in ocular pathophysiology