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We measured the intraocular pressure (IOP), blood pressure (BP), heart rate (HR), and SFCT of the left eye of 54 healthy volunteers (22 men and 32 women; mean age, 21.4 ± 3.7 years) with a best-corrected visual acuity >= 20/20, mean body mass index (BMI) of 20.8 ± 2.4 kg/m SP 2 sp (range, 15.4-29.8 kg/m SP 2 sp ), and no ophthalmic, cardiovascular, or systemic disease. The mean BP (MBP) and ocular perfusion pressure (OPP) were determined from the IOP and BP. [Extracted from the article]

Purpose: To investigate the association between long-term regular exercise (exercise frequency and exercise time) and 5-year changes in intraocular pressure in a general Japanese population. Methods: This population-based, cohort study was conducted in 2007. A total of 3119 Japanese community dwellers aged ≥ 40 years underwent eye examinations including intraocular pressure measurement with a noncontact tonometer. Of these, 1871 subjects (801 men and 1070 women) who underwent intraocular pressure measurement in 2012 participated. We assessed the associations of exercise frequency and exercise time with intraocular pressure using a linear regression model, adjusted for age and possible risk factors that can affect intraocular pressure. Results: The mean 5-year intraocular pressure change ± standard deviation was − 0.84 ± 1.9 mmHg. After adjustment for age, sex, systolic blood pressure, diabetes, total cholesterol, high-density lipoprotein cholesterol, body mass index, waist circumference, smoking habit, alcohol intake, work intensity levels, and intraocular pressure at baseline, we observed that increased exercise frequency (times/week) and increased exercise time (min/week) were both significantly associated with reduced intraocular pressure (p < 0.05 each). In the subgroup analyses based on the presence/absence of possible confounding risk factors, there was no evidence of heterogeneity among all subgroups (p for heterogeneity > 0.2). Conclusions: Increased exercise frequency levels and increased exercise time are both independently associated with reduced intraocular pressure levels after adjustment for confounding factors. [ABSTRACT FROM AUTHOR]

Background: Latanoprost is a prostaglandin (PG)F2 α analogue widely recognized in the treatment of glaucoma. To investigate the action of this drug on the ocular circulation, we have studied its effects on isolated rabbit ciliary artery. The data obtained on this drug are compared with the data from PGE2 and PGF2 α. Methods: Under the microscope, ciliary artery specimens were prepared from rabbit eyes and mounted in a myograph system. The effects of latanoprost, PGE2, and PGF2 α on the isolated rabbit ciliary artery were investigated in vitro using isometric tension recording methods. Results: Exogenously applied PGF2 α, but not latanoprost, evoked contraction in the rabbit ciliary artery. After precontraction with excess-[K]0 solution, latanoprost evoked relaxation dose-dependently. Latanoprost at a concentration of 100µM induced maximum relaxation, which was not blocked by 10 µM L-nitro-L-arginine methylester (L-NAME), 1 µM 8-37 calcitonin gene-related peptide (CGRP) or 10 µM indomethacin. Moreover, latanoprost induced relaxation even in preparations without endothelium. The maximum relaxation obtained with PGE2 was somewhat less than 50% of that with latanoprost. Conclusions: These results indicate that latanoprost and PGE2 relaxed rabbit ciliary artery to different degrees. The relaxation provoked by latanoprost was not dependent on endothelium and was not caused by intrinsic PG, CGRP or nitric oxide. The mechanism of this relaxation is not yet clear. [ABSTRACT FROM AUTHOR]

• Background and methods: In an attempt to clarify the functional action of histamine and substance P on atropine-resistant miosis, we isolated rabbit and human iris sphincter muscles and investigated their mechanical properties using the isometric tension recording method. • Results: Substance P dose-dependently contracted the rabbit iris sphincter, but had no effect on the human iris sphincter. In the rabbit iris sphincter, histamine reduced the amplitude of twitch contraction evoked by field stimulation but had no effect on carbachol-induced contraction. Thioperamide, but not mepyramine or cimetidine, partially antagonized the histamine-induced reduction in the amplitude of twitch contractions. In the human iris sphincter, on the other hand, histamine dose-dependently provoked contraction and the amplitude of histamine-induced contraction was affected neither by atropine nor by indomethacin. • Conclusions: These results provide evidence that histamine has strong contractile effect on the human iris sphincter muscle; the rabbit iris sphincter muscle, however, apparently lacks functional histamine receptors. In rabbits, exogenously applied histamine only activates H receptors located on the cholinergic nerve terminal, hence the excitatory neuro-effector transmission is suppressed. Thus, histamine may have an important roles in atropine-resistant miosis in humans, but not in rabbits. [ABSTRACT FROM AUTHOR]

To investigate the functional innervation pattern in smooth muscle of bovine ophthalmic artery, we studied the effect of electrical stimulation and various drugs on the mechanical responses of this muscle using isometric tension recording methods. Electrical stimulation evoked phasic contractions which were abolished by guanethidine and tetrodotoxin (TTX), suggesting that the responses were neurogenic in origin. Phentolamine (10 M) and 10 M timolol did not affect this contractions, but 10 M phentolamine and 10 M prazosin markedly reduced the amplitude of contraction evoked by exogenously applied phenylephrine (10 M). Electrical stimulation applied during sustained contraction evoked by 5-hydroxytryptamine in the presence of guanethidine and atropine evoked relaxation which was markedly suppressed by TTX. These results indicate that bovine ophthalmic artery is innervated by adrenergic nerve fibers, and an unidentified neurotransmitter, other than noradrenaline, may play an important role in the excitatory neuroeffector transmission, and that the tissue is also innervated by non-adrenergic non-cholinergic inhibitory nerve fibers. [ABSTRACT FROM AUTHOR]

Histological and immunohistochemical studies of a granular cell tumor involving the lower lid are described. Histological examination showed it to have typical features of a granular cell tumor. Nervous-system-specific protein (S-100 protein) was detected in both the nuclei and cytoplasm of granular cells using the peroxidase-anti-peroxidase method. This result further supports the concept of the neurogenic origin of granular cell tumors. [ABSTRACT FROM AUTHOR]

Abstract Purpose. To describe the first case of multiple retinal holes in the macular region successfully treated with vitrectomy. Method. A single case report. A 44-year-old man was treated for impaired vision caused by multiple macular holes in the right eye. Results. Fundus examinations detected six retinal holes in the right macula and a giant macular hole in the left eye. Optical coherence tomography disclosed multiple vitreoretinal adhesions in the right macula. We vitrectomized the right eye to produce posterior vitreous detachment and then tamponaded the vitreous cavity with 20% SF6 gas, resulting in closure of holes and improvement of the vision. Conclusion. Multiple macular holes may be treated by surgical posterior detachment combined with gas tamponade. Vitreoretinal adhesions are a possible cause of these holes. Similar multiple holes may have coalesced into one giant hole in this patient's left eye. [ABSTRACT FROM AUTHOR]