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Thomas W. Mittag - One of the best experts on this subject based on the ideXlab platform.
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Role of G-proteins in Ciliary Process adenylyl cyclase responses of the albino rabbit eye.
Current Eye Research, 1994Co-Authors: Thomas W. Mittag, A Tormay, Nagahisa Yoshimura, C. Severin, G. Lind, Steven M. PodosAbstract:After intravitreal injections of cholera or pertussis toxin (CTX or PTX, 0.5–1 μg/eye) into the albino rabbit eye, the in vitro responses of Ciliary Process adenylyl cyclase (AC) to isoproterenol, vasoactive intestinal peptide (VIP), and forskolin (FSK) were increased 21–40% for PTX, but for CTX-injected eyes AC responses to fluoroaluminate, VIP and FSK decreased 70–50%. The increased responses after PTX suggests that this toxin blocked an inhibitory Gi control of AC that is present in the control tissue. However, prolonged (> 24 hr) in vivo exposure to CTX appears to down-regulate the AC enzyme. In contrast to the in vivo findings, AC responsiveness was unaffected by PTX pre-treatment of membranes in vitro, while CTX pre-treatment increased basal activity (+600%), and the FSK response (+30%), but decreased responsiveness to fluoroaluminate, VIP and isoproterenol by 88–56%.Treatment of Ciliary Process membranes with 32P-NAD and CTX or PTX followed by SDS-PAGE autoradiography of labelled proteins gave two ...
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interactions between forskolin gs and divalent cations on Ciliary Process adenylyl cyclase and intraocular pressure in the rabbit eye
Experimental Eye Research, 1993Co-Authors: Thomas W. Mittag, A TormayAbstract:Abstract The major adenylyl cyclase activity (AC) of rabbit ocular Ciliary Processes was investigated by dose-response analysis with respect to interactions of its regulators [the stimulatory G-protein (αs) and forskolin] under both saturating and suboptimal divalent cation (M2+) conditions. αs was generated directly with fluoroaluminate or via receptors for vasoactive intestinal peptide or isoproterenol. Forskolin and αs when liganded simultaneously to AC at suboptimal M2+, potentiated maximal enzyme activity (approximately twice the sum of the separate activities), while the responses were additive (no potentiation) under saturating M2+ conditions. The results demonstrate that the three ligands (forskolin, M2+ and αs) mutually interact in a cooperative manner as follows: (1) The apparent kact of forskolin for AC was decreased by 1·7-1·9 log units when αs was liganded to AC. (2) Conversely, with forskolin liganded to AC the apparent kact of αs for AC also decreased by a factor of at least 3-4. (3) The nature of the divalent cation M2+ had no effect on the kact of αs for AC alone and for the AC:FSK complex, and also did not affect the apparent kact of forskolin for AC alone, or for the AC:αs complex. The nature of M2+ (Mg2+ or Mn2+) affected only the maximal catalytic rate (Emax). (4) Potentiation of adenylyl cyclase by αs + FSK was demonstrable in vivo by the increased ocular pressure response of the rabbit eye when a low topical dose of isoproterenol (125 ng per eye) and a subthreshold dose of forskolin (100 μg per eye) were given in combination.
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Effects of Al3+ and Be2+ ions combined with NaF on Ciliary Process adenylyl cyclase activity and aqueous humor dynamics in the rabbit eye.
Investigative Ophthalmology & Visual Science, 1993Co-Authors: Thomas W. Mittag, A Tormay, Cristina Severin, Rongfang Wang, T. Taniguchi, Steven M. PodosAbstract:Purpose. The activity of Al 3+ , Ga 3+ , and Be 2+ ions in the presence of NaF to directly activate G-proteins was investigated by their potentiative effect on forskolin (FSK)-activated adenylyl cyclase in rabbit Ciliary Process membranes and their effects on aqueous humor dynamics in vivo. Methods. Adenylyl cyclase (AC) was determined by radiometric conversion of ATP to cAMP by the paniculate fraction of rabbit Ciliary Processes. Intravitreal injections of sterile solutions of analytical grade salts were made into the center of the vitreous in a volume of 20 /ul. Intraocular pressure, aqueous humor flow, and uveoscleral outflow measurements were made by pneumatonometry, fluorophotometry, and fluorescein-dextran method, respectively. Outflow facility was determined by tonography in the intact eyes and by two-level constant pressure perfusion in cannulated eyes. Results. Both Al 3+ (EC50, 40 Mmol/1) and Be 2+ (EC50, 11 fimol/\) in the presence of 0.5-2 mM NaF activated the stimulatory G-protein Gs. Ga 3+ was ineffective and did not antagonize the activation by Al 3+ . Intravitreal injections of Al 3+ (1 /umol/eye) or Be 2+ (0.5 or 1 ^mol/eye) had no significant intraocular pressure (IOP) effect, nor did 1.5 or 3 jumol/eye of NaF, but when either cation was injected together with NaF, IOP decreased by up to 40% for up to 140 hr. At the time of maximum IOP effect (72 hr) aqueous humor flow determined by fluorophotometry was decreased in BeCl2+NaF-treated eyes by 40% relative to BeCl2-treated eyes; however, tonographic facility of outflow was unaffected. Uveoscleral flow was also decreased by 38% in BeCl2+NaF treated eyes. Conclusions. These findings support the hypothesis that Gs activation of Ciliary Process adenylyl cyclase decreases aqueous humor formation rate in rabbit eyes, and that activation of G-proteins mediates contraction of Ciliary muscles causing a decrease of aqueous humor outflow via the uveoscleral route. The results suggest that G-proteins putatively involved in trabecular facility changes are less sensitive to activation by BeF3~ than are other parameters of aqueous humor dynamics. Invest Ophthalmol Vis Sci. 1993;34:606-612.
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Polylysine stimulated protein phosphorylation in rabbit Ciliary Processes: casein kinase activities.
Experimental Eye Research, 1993Co-Authors: Thomas W. Mittag, A Tormay, Nagahisa Yoshimura, Steven M. PodosAbstract:Protein phosphorylation in response to polylysine was investigated in vitro in rabbit Ciliary Process homogenates by SDS-PAGE autoradiography. The degree of phosphorylation was greater in the soluble/cytoplasmic fraction than in the particulate fraction and was antagonized by heparin. Time and dose-dependent studies indicated several different kinetic patterns of phosphorylation/dephosphorylation among the approximately 15 significantly 32 P-labeled bands found in each fraction. These results are consistent with phosphorylation of endogenous substrates by casein kinase II, and dephosphorylations by type I and type II phosphoprotein phosphatase enzymes. The presence of EGF receptors in Ciliary Processes was indicated by high affinity (kD < 0·5 nM) binding sites and by intraocular pressure and blood-aqueous barrier responses to injection of low doses of EGF (100 ng per eye). EGF did not stimulate protein phosphorylation in Ciliary Process homogenates in vitro. The results show that casein kinase II is a significant kinase activity in Ciliary Processes and may have a modulatory role on signal transduction proteins involved in cellular response to hormones.
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Interaction of vanadate and iodate oxyanions with adenylyl cyclase of Ciliary Processes.
Biochemical Pharmacology, 1993Co-Authors: Thomas W. Mittag, Wen-bin Guo, Toru TaniguchiAbstract:Abstract Vanadate (VO 3 − ) was found to activate adenylyl cyclase (AC) in ocular Ciliary Process membrane. This response was additive to that of isoproterenol (ISO) and vasoactive intestinal peptide (VIP), but it was potentiative with forskolin (FSK) and also with Ca 2+ /calmodulin activation of AC activity. The potentiated response of FSK in the presence of VO 3 − was due to an increase in V max without a change in the apparent affinity of FSK or VO 3 − , and therefore differs froin the potentiated response of activated G-protein (G s ) and FSK, where the affinity of FSK was increased by 1–2 orders of magnitude. Potentiation occurred at low Mg 2+ and was not observed at free [Mg 2+ ] > 3 mM. Iodate (IO 3 − ) inhibited the FSK, ISO, and VO 3 − activations of AC in Ciliary Process membranes ( ic 50 , 0.3 mM). In vivo topical treatment of the rabbit eye with 50μL of 5% NaIO 3 had no effect alone but completely blocked the intraocular pressure response to a 50-μL topical dose of 1% FSK and partially blocked the response to a 50-μL dose of 0.001% ISO. These findings indicate that some AC enzymes may have a binding site for oxyanions which can directly regulate enzyme activity.
A Tormay - One of the best experts on this subject based on the ideXlab platform.
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Role of G-proteins in Ciliary Process adenylyl cyclase responses of the albino rabbit eye.
Current Eye Research, 1994Co-Authors: Thomas W. Mittag, A Tormay, Nagahisa Yoshimura, C. Severin, G. Lind, Steven M. PodosAbstract:After intravitreal injections of cholera or pertussis toxin (CTX or PTX, 0.5–1 μg/eye) into the albino rabbit eye, the in vitro responses of Ciliary Process adenylyl cyclase (AC) to isoproterenol, vasoactive intestinal peptide (VIP), and forskolin (FSK) were increased 21–40% for PTX, but for CTX-injected eyes AC responses to fluoroaluminate, VIP and FSK decreased 70–50%. The increased responses after PTX suggests that this toxin blocked an inhibitory Gi control of AC that is present in the control tissue. However, prolonged (> 24 hr) in vivo exposure to CTX appears to down-regulate the AC enzyme. In contrast to the in vivo findings, AC responsiveness was unaffected by PTX pre-treatment of membranes in vitro, while CTX pre-treatment increased basal activity (+600%), and the FSK response (+30%), but decreased responsiveness to fluoroaluminate, VIP and isoproterenol by 88–56%.Treatment of Ciliary Process membranes with 32P-NAD and CTX or PTX followed by SDS-PAGE autoradiography of labelled proteins gave two ...
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interactions between forskolin gs and divalent cations on Ciliary Process adenylyl cyclase and intraocular pressure in the rabbit eye
Experimental Eye Research, 1993Co-Authors: Thomas W. Mittag, A TormayAbstract:Abstract The major adenylyl cyclase activity (AC) of rabbit ocular Ciliary Processes was investigated by dose-response analysis with respect to interactions of its regulators [the stimulatory G-protein (αs) and forskolin] under both saturating and suboptimal divalent cation (M2+) conditions. αs was generated directly with fluoroaluminate or via receptors for vasoactive intestinal peptide or isoproterenol. Forskolin and αs when liganded simultaneously to AC at suboptimal M2+, potentiated maximal enzyme activity (approximately twice the sum of the separate activities), while the responses were additive (no potentiation) under saturating M2+ conditions. The results demonstrate that the three ligands (forskolin, M2+ and αs) mutually interact in a cooperative manner as follows: (1) The apparent kact of forskolin for AC was decreased by 1·7-1·9 log units when αs was liganded to AC. (2) Conversely, with forskolin liganded to AC the apparent kact of αs for AC also decreased by a factor of at least 3-4. (3) The nature of the divalent cation M2+ had no effect on the kact of αs for AC alone and for the AC:FSK complex, and also did not affect the apparent kact of forskolin for AC alone, or for the AC:αs complex. The nature of M2+ (Mg2+ or Mn2+) affected only the maximal catalytic rate (Emax). (4) Potentiation of adenylyl cyclase by αs + FSK was demonstrable in vivo by the increased ocular pressure response of the rabbit eye when a low topical dose of isoproterenol (125 ng per eye) and a subthreshold dose of forskolin (100 μg per eye) were given in combination.
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Effects of Al3+ and Be2+ ions combined with NaF on Ciliary Process adenylyl cyclase activity and aqueous humor dynamics in the rabbit eye.
Investigative Ophthalmology & Visual Science, 1993Co-Authors: Thomas W. Mittag, A Tormay, Cristina Severin, Rongfang Wang, T. Taniguchi, Steven M. PodosAbstract:Purpose. The activity of Al 3+ , Ga 3+ , and Be 2+ ions in the presence of NaF to directly activate G-proteins was investigated by their potentiative effect on forskolin (FSK)-activated adenylyl cyclase in rabbit Ciliary Process membranes and their effects on aqueous humor dynamics in vivo. Methods. Adenylyl cyclase (AC) was determined by radiometric conversion of ATP to cAMP by the paniculate fraction of rabbit Ciliary Processes. Intravitreal injections of sterile solutions of analytical grade salts were made into the center of the vitreous in a volume of 20 /ul. Intraocular pressure, aqueous humor flow, and uveoscleral outflow measurements were made by pneumatonometry, fluorophotometry, and fluorescein-dextran method, respectively. Outflow facility was determined by tonography in the intact eyes and by two-level constant pressure perfusion in cannulated eyes. Results. Both Al 3+ (EC50, 40 Mmol/1) and Be 2+ (EC50, 11 fimol/\) in the presence of 0.5-2 mM NaF activated the stimulatory G-protein Gs. Ga 3+ was ineffective and did not antagonize the activation by Al 3+ . Intravitreal injections of Al 3+ (1 /umol/eye) or Be 2+ (0.5 or 1 ^mol/eye) had no significant intraocular pressure (IOP) effect, nor did 1.5 or 3 jumol/eye of NaF, but when either cation was injected together with NaF, IOP decreased by up to 40% for up to 140 hr. At the time of maximum IOP effect (72 hr) aqueous humor flow determined by fluorophotometry was decreased in BeCl2+NaF-treated eyes by 40% relative to BeCl2-treated eyes; however, tonographic facility of outflow was unaffected. Uveoscleral flow was also decreased by 38% in BeCl2+NaF treated eyes. Conclusions. These findings support the hypothesis that Gs activation of Ciliary Process adenylyl cyclase decreases aqueous humor formation rate in rabbit eyes, and that activation of G-proteins mediates contraction of Ciliary muscles causing a decrease of aqueous humor outflow via the uveoscleral route. The results suggest that G-proteins putatively involved in trabecular facility changes are less sensitive to activation by BeF3~ than are other parameters of aqueous humor dynamics. Invest Ophthalmol Vis Sci. 1993;34:606-612.
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Polylysine stimulated protein phosphorylation in rabbit Ciliary Processes: casein kinase activities.
Experimental Eye Research, 1993Co-Authors: Thomas W. Mittag, A Tormay, Nagahisa Yoshimura, Steven M. PodosAbstract:Protein phosphorylation in response to polylysine was investigated in vitro in rabbit Ciliary Process homogenates by SDS-PAGE autoradiography. The degree of phosphorylation was greater in the soluble/cytoplasmic fraction than in the particulate fraction and was antagonized by heparin. Time and dose-dependent studies indicated several different kinetic patterns of phosphorylation/dephosphorylation among the approximately 15 significantly 32 P-labeled bands found in each fraction. These results are consistent with phosphorylation of endogenous substrates by casein kinase II, and dephosphorylations by type I and type II phosphoprotein phosphatase enzymes. The presence of EGF receptors in Ciliary Processes was indicated by high affinity (kD < 0·5 nM) binding sites and by intraocular pressure and blood-aqueous barrier responses to injection of low doses of EGF (100 ng per eye). EGF did not stimulate protein phosphorylation in Ciliary Process homogenates in vitro. The results show that casein kinase II is a significant kinase activity in Ciliary Processes and may have a modulatory role on signal transduction proteins involved in cellular response to hormones.
Steven M. Podos - One of the best experts on this subject based on the ideXlab platform.
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Role of G-proteins in Ciliary Process adenylyl cyclase responses of the albino rabbit eye.
Current Eye Research, 1994Co-Authors: Thomas W. Mittag, A Tormay, Nagahisa Yoshimura, C. Severin, G. Lind, Steven M. PodosAbstract:After intravitreal injections of cholera or pertussis toxin (CTX or PTX, 0.5–1 μg/eye) into the albino rabbit eye, the in vitro responses of Ciliary Process adenylyl cyclase (AC) to isoproterenol, vasoactive intestinal peptide (VIP), and forskolin (FSK) were increased 21–40% for PTX, but for CTX-injected eyes AC responses to fluoroaluminate, VIP and FSK decreased 70–50%. The increased responses after PTX suggests that this toxin blocked an inhibitory Gi control of AC that is present in the control tissue. However, prolonged (> 24 hr) in vivo exposure to CTX appears to down-regulate the AC enzyme. In contrast to the in vivo findings, AC responsiveness was unaffected by PTX pre-treatment of membranes in vitro, while CTX pre-treatment increased basal activity (+600%), and the FSK response (+30%), but decreased responsiveness to fluoroaluminate, VIP and isoproterenol by 88–56%.Treatment of Ciliary Process membranes with 32P-NAD and CTX or PTX followed by SDS-PAGE autoradiography of labelled proteins gave two ...
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Effects of Al3+ and Be2+ ions combined with NaF on Ciliary Process adenylyl cyclase activity and aqueous humor dynamics in the rabbit eye.
Investigative Ophthalmology & Visual Science, 1993Co-Authors: Thomas W. Mittag, A Tormay, Cristina Severin, Rongfang Wang, T. Taniguchi, Steven M. PodosAbstract:Purpose. The activity of Al 3+ , Ga 3+ , and Be 2+ ions in the presence of NaF to directly activate G-proteins was investigated by their potentiative effect on forskolin (FSK)-activated adenylyl cyclase in rabbit Ciliary Process membranes and their effects on aqueous humor dynamics in vivo. Methods. Adenylyl cyclase (AC) was determined by radiometric conversion of ATP to cAMP by the paniculate fraction of rabbit Ciliary Processes. Intravitreal injections of sterile solutions of analytical grade salts were made into the center of the vitreous in a volume of 20 /ul. Intraocular pressure, aqueous humor flow, and uveoscleral outflow measurements were made by pneumatonometry, fluorophotometry, and fluorescein-dextran method, respectively. Outflow facility was determined by tonography in the intact eyes and by two-level constant pressure perfusion in cannulated eyes. Results. Both Al 3+ (EC50, 40 Mmol/1) and Be 2+ (EC50, 11 fimol/\) in the presence of 0.5-2 mM NaF activated the stimulatory G-protein Gs. Ga 3+ was ineffective and did not antagonize the activation by Al 3+ . Intravitreal injections of Al 3+ (1 /umol/eye) or Be 2+ (0.5 or 1 ^mol/eye) had no significant intraocular pressure (IOP) effect, nor did 1.5 or 3 jumol/eye of NaF, but when either cation was injected together with NaF, IOP decreased by up to 40% for up to 140 hr. At the time of maximum IOP effect (72 hr) aqueous humor flow determined by fluorophotometry was decreased in BeCl2+NaF-treated eyes by 40% relative to BeCl2-treated eyes; however, tonographic facility of outflow was unaffected. Uveoscleral flow was also decreased by 38% in BeCl2+NaF treated eyes. Conclusions. These findings support the hypothesis that Gs activation of Ciliary Process adenylyl cyclase decreases aqueous humor formation rate in rabbit eyes, and that activation of G-proteins mediates contraction of Ciliary muscles causing a decrease of aqueous humor outflow via the uveoscleral route. The results suggest that G-proteins putatively involved in trabecular facility changes are less sensitive to activation by BeF3~ than are other parameters of aqueous humor dynamics. Invest Ophthalmol Vis Sci. 1993;34:606-612.
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Polylysine stimulated protein phosphorylation in rabbit Ciliary Processes: casein kinase activities.
Experimental Eye Research, 1993Co-Authors: Thomas W. Mittag, A Tormay, Nagahisa Yoshimura, Steven M. PodosAbstract:Protein phosphorylation in response to polylysine was investigated in vitro in rabbit Ciliary Process homogenates by SDS-PAGE autoradiography. The degree of phosphorylation was greater in the soluble/cytoplasmic fraction than in the particulate fraction and was antagonized by heparin. Time and dose-dependent studies indicated several different kinetic patterns of phosphorylation/dephosphorylation among the approximately 15 significantly 32 P-labeled bands found in each fraction. These results are consistent with phosphorylation of endogenous substrates by casein kinase II, and dephosphorylations by type I and type II phosphoprotein phosphatase enzymes. The presence of EGF receptors in Ciliary Processes was indicated by high affinity (kD < 0·5 nM) binding sites and by intraocular pressure and blood-aqueous barrier responses to injection of low doses of EGF (100 ng per eye). EGF did not stimulate protein phosphorylation in Ciliary Process homogenates in vitro. The results show that casein kinase II is a significant kinase activity in Ciliary Processes and may have a modulatory role on signal transduction proteins involved in cellular response to hormones.
Roberto Freire Santiago Malta - One of the best experts on this subject based on the ideXlab platform.
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long Ciliary Processes with no Ciliary sulcus and appositional angle closure assessed by ultrasound biomicroscopy
Journal of Glaucoma, 2006Co-Authors: Lisandro Massanori Sakata, Kenji Sakata, Remo Susanna, Viviane Mayumi Sakata, Marcelo Hatanaka, Luisa Trancoso, Julio De Leon Ortega, Roberto Freire Santiago MaltaAbstract:PURPOSE Nonpupil block mechanisms and appositional angle closure after laser iridotomy (LI) have been reported as common findings in Asians. We evaluated the presence of these findings in a cohort of Brazilian patients using ultrasound biomicroscopy (UBM). METHODS This observational case-control study included 22 open angle eyes and 31 eyes with occludable angles on gonioscopy (defined by 2 examiners). UBM radial scans through a typical Ciliary Process were obtained in both light and dark conditions, at 6 and 12-o'clock positions. Long Ciliary Processes with no Ciliary sulcus were determined on the basis of a reference line drawn perpendicular to the iris plane passing through a point located 750 mum from scleral spur. Trabecular Ciliary Processes distance was measured on 6-o'clock UBM images. RESULTS After LI, 52% of occludable angle eyes had appositional angle closure in both 6 and 12-o'clock UBM images. We also observed this finding in 14% and 23% of the control eyes (in 6 and 12-o'clock UBM images, respectively). A long Ciliary Process with no Ciliary sulcus was observed in 61% of occludable angle eyes, and also in 32% of control eyes (6-o'clock UBM images). Control eyes had longer trabecular Ciliary Processes distance than occludable angle eyes (P<0.001). CONCLUSIONS The UBM finding of long Ciliary Processes associated with the absence of Ciliary sulcus is not necessarily related to an anterior positioning of the Ciliary Processes. Whether UBM appositional angle closure after LI is associated with further angle closure Process and/or poor intra-ocular pressure control remains to be evaluated.
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Long Ciliary Processes with no Ciliary sulcus and appositional angle closure assessed by ultrasound biomicroscopy.
Journal of Glaucoma, 2006Co-Authors: Lisandro Massanori Sakata, Kenji Sakata, Remo Susanna, Viviane Mayumi Sakata, Marcelo Hatanaka, Luisa Trancoso, Julio De Leon Ortega, Roberto Freire Santiago MaltaAbstract:PURPOSE Nonpupil block mechanisms and appositional angle closure after laser iridotomy (LI) have been reported as common findings in Asians. We evaluated the presence of these findings in a cohort of Brazilian patients using ultrasound biomicroscopy (UBM). METHODS This observational case-control study included 22 open angle eyes and 31 eyes with occludable angles on gonioscopy (defined by 2 examiners). UBM radial scans through a typical Ciliary Process were obtained in both light and dark conditions, at 6 and 12-o'clock positions. Long Ciliary Processes with no Ciliary sulcus were determined on the basis of a reference line drawn perpendicular to the iris plane passing through a point located 750 mum from scleral spur. Trabecular Ciliary Processes distance was measured on 6-o'clock UBM images. RESULTS After LI, 52% of occludable angle eyes had appositional angle closure in both 6 and 12-o'clock UBM images. We also observed this finding in 14% and 23% of the control eyes (in 6 and 12-o'clock UBM images, respectively). A long Ciliary Process with no Ciliary sulcus was observed in 61% of occludable angle eyes, and also in 32% of control eyes (6-o'clock UBM images). Control eyes had longer trabecular Ciliary Processes distance than occludable angle eyes (P
Yasuo Kurimoto - One of the best experts on this subject based on the ideXlab platform.
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Angle widening and alteration of Ciliary Process configuration after cataract surgery for primary angle closure.
Ophthalmology, 2006Co-Authors: Atsushi Nonaka, Takehisa Kondo, Masashi Kikuchi, Kenji Yamashiro, Masashi Fujihara, Takuji Iwawaki, Kaoruko Yamamoto, Yasuo KurimotoAbstract:Purpose To evaluate quantitatively, by means of ultrasound biomicroscopy (UBM), changes in the anterior segment configuration, including the Ciliary Processes, induced by cataract surgery in eyes with primary angle closure. Design Retrospective interventional case series. Participants Thirty-one eyes of 31 patients with primary angle closure or primary angle-closure glaucoma were treated with cataract surgery. Before cataract surgery, 10 eyes had been treated with laser peripheral iridotomy, and 1 with laser peripheral iridoplasty. Methods Configuration of the anterior chamber was examined by means of UBM before and at 3 months after cataract surgery. Main Outcome Measures Using UBM, anterior chamber depth (ACD), angle opening distance at points 500 μm from the scleral spur (AOD500), and trabecular–Ciliary Process distance (TCPD) were measured. Results Not only ACD and AOD500, but also TCPD, increased significantly after cataract surgery, compared with measurements obtained before surgery ( P r = 0.72, P r = 0.52, P Conclusions Cataract surgery attenuated anterior positioning of the Ciliary Processes in eyes with primary angle closure, concomitant with significant widening of the angle. Cataract surgery resulted in not only complete dissolution of lens volume and pupillary block, but also attenuation of the anterior positioning of the Ciliary Processes, all of which contributed to postoperative widening of the angle in eyes with primary angle closure.