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Purpose To elucidate the dynamic accommodative movements of the lens capsule, posterior lens and the strand that attaches to the posterior vitreous zonule insertion zone and posterior lens equator (PVZ INS-LE), and their age-related changes. Methods Twelve human subjects (ages 19–65 years) and 12 rhesus monkeys (ages 6–27 years) were studied. Accommodation was induced pharmacologically (humans) or by central electrical stimulation (monkeys). Ultrasound biomicroscopy was used to image intraocular structures in both species. Surgical procedures and contrast agents were utilized in the monkey eyes to elucidate function and allow visualization of the intraocular accommodative structures. Results Human: The posterior pole of the lens moves posteriorly during accommodation in proportion to accommodative amplitude and ciliary muscle movement. Monkey: Similar accommodative movements of the posterior lens pole were seen in the monkey eyes. Following extracapsular lens extraction (ECLE), the central capsule bows backward during accommodation in proportion to accommodative amplitude and ciliary muscle movement, while the peripheral capsule moves forward. During accommodation the ciliary muscle moved forward by ~1.0 mm, pulling forward the vitreous zonule and the PVZ INS-LE structure. During the accommodative response the PVZ INS-LE structure moved forward when the lens was intact and when the lens substance and capsule were removed. In both the monkey and the human eyes these movements declined with age. Conclusions The accommodative shape change of the central capsule may be due to the elastic properties of the capsule itself. For these capsule/lens accommodative posterior movements to occur, the vitreous face must either allow for it or facilitate it. The PVZ INS-LE structure may act as a ‘strut’ to the posterior lens equator (pushing the lens equator forward) and thereby facilitate accommodative forward lens equator movement and lens thickening. The age-related posterior restriction of the ciliary muscle, vitreous zonule and the PVZ-INS LE structure dampens the accommodative lens shape change. Future descriptions of the accommodative mechanism, and approaches to presbyopia therapy, may need to incorporate these findings.

OBJECTIVE To compare the efficacy of the nonvalved double-plate Molteno implant with two valved implants, the Krupin Eye Valve with Disc and the Ahmed Glaucoma Valve, in the treatment of recalcitrant glaucoma. PATIENTS AND METHODS The authors performed a nonrandomized retrospective review of patients who received the Molteno implant (n = 27), Krupin Eye Valve with Disc (n = 13), or Ahmed Glaucoma Valve (n = 13), with adjunctive mitomycin C. RESULTS Kaplan-Meier life-table analysis showed that the Molteno implant patients were more likely to maintain an intraocular pressure between 5 and 15 mm Hg than Ahmed Glaucoma Valve patients (P = 0.03). Success rates at 1 year were 80% (95% CI, 66-97%) for the Molteno implant, 39% (19-77%) for the Krupin Eye Valve with Disc, and 35% (15-82%) for the Ahmed Glaucoma Valve. However, Ahmed Glaucoma Valve patients were less likely to experience complications requiring reoperation or loss of two or more lines of visual acuity (P < 0.01) than Molteno implant or Krupin Eye Valve with Disc patients. CONCLUSIONS This nonrandomized study suggests that the Molteno implant with mitomycin C is more likely to result in intraocular pressures in the lower teens than the Ahmed Glaucoma Valve with mitomycin C. The findings suggest that the Ahmed implant is less likely to create problems leading to reoperations or visual acuity loss than the Molteno or Krupin implants.

Purpose The purpose of this study is to evaluate effects of vitrectomy (PPV) and lens extraction with intraocular lens implantation (PE/IOL) on molecular oxygen (pO2) distribution, aqueous humor antioxidant-oxidant balance, aqueous humor dynamics, and histopathologic changes in the trabecular meshwork (TM) in the older macaque monkey. Methods Six rhesus monkeys underwent PPV followed by PE/IOL. pO2, outflow facility, and intraocular pressure (IOP) were measured. Aqueous and vitreous humor specimens were analyzed for antioxidant status and 8-hydroxy-2'-deoxyguanosine (8-OHdG), a marker of oxidative damage. TM specimens were obtained for immunohistochemical and quantitative PCR analysis. Results pO2 at baseline revealed steep gradients in the anterior chamber and low levels in the posterior chamber (PC) and around the lens. Following PPV and PE/IOL, pO2 significantly increased in the PC, around the IOL, and angle. IOP increased following both surgical interventions, with no change in outflow facility. Histopathologic analysis did not show changes in TM cell quantification, but there was an increase in 8-OHdG. Quantitative PCR did not reveal significant differences in glaucoma-related gene expression. Aqueous and vitreous humor analysis revealed decreased ascorbate and total reactive antioxidant potential and increased 8-OHdG in the aqueous humor only in the surgical eyes. Conclusions Oxygen distribution in the older rhesus monkey is similar to humans at baseline and following surgical interventions. Our findings of histopathologic changes of TM oxidative damage and alterations in the oxidant-antioxidant balance suggest a potential correlation of increased oxygen exposure with oxidative stress/damage and the development of open angle glaucoma.

Purpose: To determine efficacy and safety of latanoprost, a prostaglandin analog for glaucoma, during 1 year of treatment. Methods: After baseline measurements, 0.005% latanoprost was topically applied once daily for 12 months in patients from Scandinavia, the United Kingdom, and the United States who had elevated intraocular pressure (IOP). Diagnoses included ocular hypertension, chronic open-angle glaucoma, exfoliation syndrome, and pigment dispersion syndrome. Treatment was masked for the first 6 months and open-label during the second 6 months. Results: Of the 272 patients initially enrolled, withdrawals were due to inadequate IOP control (1 %), increased iris pigmentation (5%), other ocular problems (3%), systemic medical problems (3%), and nonmedical reasons (14%). Latanoprost significantly ( P Conclusion: Latanoprost safely and effectively reduces IOP for 1 year in patients of diverse nationalities, providing further evidence for its usefulness in chronic glaucoma therapy.

This study is aimed to determine if the serine-threonine kinase inhibitor H-7 inhibits secondary cataract after phacoemulsification in the live rabbit eye.Eighteen rabbits underwent extracapsular lens extraction by phacoemulsification in 1 eye. The eye was treated with intravitreal H-7 (300 or 1,200 μM; n = 6 or 5) or balanced salt solution (BSS) (n = 7) immediately after the surgery and twice weekly for 10 weeks. Each eye received slit lamp biomicroscopy once a week, during which posterior capsule opacification (PCO) was evaluated. The eye was then enucleated and the lens capsule was prepared, fixed, and imaged. PCO was evaluated again on the isolated lens capsule under a phase microscope. Soemmering's ring area (SRA) and the entire lens capsule area were measured from capsule images on a computer and the percentage of SRA (PSRA) in the entire capsule area was calculated. Wet weight of the capsule (WW) was determined on a balance.No significant difference in PCO was observed in any comparison. No significant differences in SRA, PSRA, and WW were observed between the 300 μM H-7-treated eye and the BSS-treated eye. However, SRA, PSRA, and WW in the 1,200 μM H-7-treated eye were significantly smaller than those in the BSS-treated eye [28.3 ± 16.2 vs. 61.4 ± 8.86 mm(2) (P = 0.001), 33% ± 20% vs. 65% ± 15% (P = 0.01), and 65.6 ± 27.9 vs. 127.0 ±37.3 mg (P = 0.01)].Intravitreal H-7 (1,200 μM) significantly inhibits Soemmering's ring formation in the live rabbit eye, suggesting that agents that inhibit the actomyosin system in cells may prevent secondary cataract after phacoemulsification.

Purpose To determine how surgically altering the normal relationship between the lens and the ciliary body in rhesus monkeys affects centripetal ciliary body and lens movement. Methods In 18 rhesus monkey eyes (aged 6-27 years), accommodation was induced before and after surgery by electrical stimulation of the Edinger-Westphal nucleus. Accommodative amplitude was measured by coincidence refractometry. Goniovideography was performed before and after intra- and extracapsular lens extraction (ICLE, ECLE) and anterior regional zonulolysis (ARZ). Centripetal lens/capsule movements, centripetal ciliary process (CP) movements, and circumlental space were measured by computerized image analysis of the goniovideography images. Results Centripetal accommodative CP and capsule movement increased in velocity and amplitude after, compared with before, ECLE regardless of age (n = 5). The presence of the lens substance retarded capsule movement by approximately 21% in the young eyes and by approximately 62% in the older eyes. Post-ICLE compared with pre-ICLE centripetal accommodative CP movement was dampened in all eyes in which the anterior vitreous was disrupted (n = 7), but not in eyes in which the anterior vitreous was left intact (n = 2). After anterior regional zonulolysis (n = 4), lens position shifted toward the lysed quadrant during accommodation. Conclusions The presence of the lens substance, capsule zonular attachments, and Wieger's ligament may play a role in centripetal CP movement. The capsule is still capable of centripetal movement in the older eye (although at a reduced capacity) and may have the ability to produce approximately 6 D of accommodation in the presence of a normal, young crystalline lens or a similar surrogate.

Recent reports from large clinical trials have clearly demonstrated that lowering intraocular pressure (IOP) in persons with ocular hypertension has a beneficial effect on reducing the progression of glaucomatous disease. Few studies of this effect have been conducted in controlled laboratory settings, however, none have been conducted using non-human primates, the model of experimental glaucoma considered most similar to the human disease. Using data collected retrospectively from a trabeculectomy study using 16 cynomolgous monkeys with experimental ocular hypertension, we evaluated both the threshold of elevated IOP required to cause clinically observable damage to the optic nerve head and also if lowering IOP below this threshold prevents further damage. An index of the level of elevated IOP experienced by experimental eyes (the Pressure Insult) was calculated as the slope of the difference in cumulative IOP between experimental and control eyes during four intervals of time over the course of the experiment, while damage to the optic nerve head was evaluated by measuring the Cup:Disc ratio for each eye from stereoscopic photographs taken at the end of each interval. An increase in the Cup:Disc ratio was significantly associated with both the maximum IOP obtained in the experimental eye during each interval (r = 0.573, P < 0.001) and the Pressure Insult (r = 0.496, P < 0.001). Pressure Insult values less than 11 mm Hg Days/Day were not associated with glaucomatous damage in monkey eyes, whereas values greater than 11 showed a significant correlation with increasing Cup:Disc ratios (P < 0.001). Trabeculectomy to reduce the Pressure Insult below 11 was correlated with an attenuation of the rate of progression of the Cup:Disc ratio in eyes that had exhibited damage before surgery. These results contribute further to our understanding of this model of experimental glaucoma by demonstrating a threshold at which IOP needs to be elevated to stimulate damage, while also providing corroborating evidence that lowering IOP in ocular hypertensive monkeys can attenuate the progression of glaucomatous disease.

Objectives To determine the incidence of late-onset bleb-related complications following trabeculectomy with mitomycin and to report the management and outcome of bleb leaks following trabeculectomy with mitomycin. Methods A retrospective medical record review of all patients who underwent trabeculectomy with mitomycin from June 1, 1991, through April 30, 1998, at our institution was performed. The Kaplan-Meier survival method was used to estimate the probability of (1) endophthalmitis, (2) blebitis, (3) a bleb leak, and (4) the combined outcome (the first occurrence of a bleb leak, blebitis, or endophthalmitis). This survival analysis included only the first trabeculectomy in an eye, with at least 3 months of follow-up during the study period. A separate description of bleb leak management and outcome was performed. Results Two hundred thirty-nine eyes of 198 patients were included in the survival analysis. The average follow-up was 2.7 (range, 0.3-7.3) years. Twenty eyes(8%) from 19 patients experienced a bleb leak; the adjusted incidence was 3.2% per patient-year. Five eyes (2%) had an episode of blebitis. Eight eyes(3%) experienced an episode of endophthalmitis; the follow-up adjusted incidence(number of events per patient-year) was 1.3%. Twenty-seven eyes (11%) from 26 patients had at least 1 of the complications of a bleb leak, blebitis, or endophthalmitis; the adjusted incidence was 4.4% per patient-year. A Kaplan-Meier analysis estimated the 5-year probability of developing a bleb leak, blebitis, or endophthalmitis to be 17.9%, 6.3%, and 7.5%, respectively. Two hundred fifty-eight trabeculectomies in 242 eyes of 198 patients were included in the description of bleb leak management and outcome. Bleb leaks occurred in 22 eyes (9% of the 258 trabeculectomies). Seventeen eyes were successfully treated with office-based measures, and 4 ultimately underwent surgical bleb revision. One eye without infection continued to leak after 11 months of office-based therapy. Conclusions There is significant morbidity associated with a trabeculectomy with mitomycin. The incidence of a bleb leak or an infection continues at a fairly constant rate over time, such that at 5 years, up to 23% of all patients might develop one of these complications. An isolated bleb leak seems to be a relatively benign condition, as three quarters resolve with office-based methods.

Objective To determine the incidence of intraocular pressure (IOP) rise of varying degrees after laser peripheral iridotomy (LPI) in patients with and without glaucoma treated perioperatively with pilocarpine and apraclonidine. Design A retrospective chart review. Participants A total of 289 eyes in 179 patients with narrow occludable angles (NOA) (N = 148), open-angle glaucoma or ocular hypertension (OAG) (N = 115), or chronic-angle closure glaucoma (CACG) (N = 26) were reviewed. Main outcome measures The difference between preoperative and postoperative IOP, absolute postop- erative IOP, and the need for acute IOP-lowering treatment was noted. Results Only 1.1% (95% confidence interval [CI], 0.03%–5.8%; 1 of 94) of patients and 0.7% (95% CI, 0.02%–3.7%; 1 of 148) of eyes with NOA experienced a rise of more than 10 mmHg 1 to 2 hours after LPI. The incidence of postoperative IOP greater than 25 mmHg and acute postoperative IOP-lowering management was 0% (95% CI, 0%–3.8%). Intraocular pressure in 1 of 115 eyes (0.9%, 95% CI, 0.02%–4.7%) with OAG rose more than 10 mmHg, requiring acute treatment. None of the 26 CACG eyes experienced a rise of more than 10 mmHg (95% CI, 0%–13.2%). Conclusion The IOP rise that requires further intervention after LPI with the perioperative use of pilocarpine and apraclonidine is very uncommon. In patients with NOA, routine postiridotomy IOP monitoring may not be required.

Purpose: The authors assessed the efficacy of adjunctive intraoperative mitomycin C to produce lower intraocular pressures (IOPs) in patients with complicated glaucoma who underwent double-plate Molteno implantation. Methods: A pilot series of 21 consecutive patients who underwent double-plate Molteno implantation with adjunctive intraoperative mitomycin C (0.5 mg/ml) for 5 minutes was compared with a historical control group who received Molteno implants without mitomycin C (n = 18). With failure defined as an IOP greater than 21 or less than 6 mmHg at two observations 1 month apart, the addition of medication, re-operation for glaucoma, or tube removal, a life-table analysis of IOP was performed on patients with at least 3 months' follow-up. Results: Success in the mitomycin C group was higher (68% at 1 year) than the control group (17% at 1 year; P = 0.006). Loss of more than one line of vision (33%) and re-operation for complications (including flat anterior chamber, choroidal detachment, and tube blockage) (38%) were slightly but not significantly more frequent in the mitomycin C group than in the control group. Conclusion: This study suggests that intraoperative mitomycin C in conjunction with Molteno implant may offer a better chance of achieving target IOPs in the low teens in patients with complicated glaucoma than Molteno implantation alone.

PURPOSE To determine the role of the lens and the lens capsule in the three-dimensional architecture of the ciliary muscle at rest and during accommodation, in live rhesus monkeys and in histologic sections, by removing the entire lens, or only the lens nucleus and cortex, while leaving the posterior capsule in place. METHODS In 15 rhesus monkey eyes, aged 6 to 27 years, accommodation was induced by central stimulation of the Edinger-Westphal nucleus before and after intra- or extracapsular lens extraction (ICLE, ECLE). Forward ciliary body movement and ciliary body width were measured by ultrasound biomicroscopy (UBM, 50 MHz). The monkeys were then killed, the eyes were examined morphologically in 1-microm sections, and the shape of the ciliary muscle was compared with that obtained from UBM images. RESULTS The shape of the ciliary muscle in eyes undergoing ECLE (n = 5) did not differ from that in control eyes. In contrast, after ICLE (n = 10), accommodative forward ciliary body movement (P < 0.01) and thickness were decreased (P < 0.001), length was increased (P = 0.058), and the inner apex was located more posteriorly than in control eyes (P < 0.005). Histologic and in vivo data were similar and showed that the ciliary muscle maintained its triangular shape only if the lens capsule (with or without the lens substance) was present. CONCLUSIONS The posterior lens capsule and anterior zonular attachments facilitate forward accommodative ciliary body movement. Lens substance extraction procedures that leave the posterior capsule intact, similar to those used clinically, do not affect the capsule/zonular/muscular system movements, an important finding for accommodating intraocular lens development.

PURPOSE The underlying causes of presbyopia, and the functional relationship between the ciliary muscle and lens during aging are unclear. In the current study, these relationships were studied in rhesus monkeys, whose accommodative apparatus and age-related loss of accommodation are similar to those in humans. METHODS Centripetal ciliary body and lens equator movements were measured during accommodation in 28 eyes of 21 rhesus monkeys (ages, 5.7-26 years) by goniovideography. Ultrasound biomicroscopy was performed in 21 eyes of 17 monkeys. Narrowing of the angle between the anterior aspect of the ciliary body and the inner aspect of the cornea was used as a surrogate indicator of forward ciliary body movement during accommodation. RESULTS Average centripetal ciliary body movement in older eyes (age > or =17 years, n = 16) was approximately 20% (0.09 mm) less than in young eyes (age, 6-10 years, n = 6), but not enough to explain the 60% (0.21 mm) loss in centripetal lens movement nor the 76% (10.2 D) loss in accommodative amplitude. Average forward ciliary body movement was 67% (49 degrees ) less in older (n = 11) versus young (n = 6) eyes. Maximum accommodative amplitude correlated significantly with the amplitude of centripetal lens movement (0.02 +/- 0.003 mm/D; n = 28; P < 0.001) and with forward ciliary body movement (3.34 +/- 0.54 deg/D; n = 21; P = 0.01). CONCLUSIONS Decreased lens movement with age could be in part secondary to extralenticular age-related changes, such as loss of ciliary body forward movement. Ciliary body centripetal movement may not be the limiting component in accommodation in the older eye.

Purpose This study was performed to provide results 2 to 3 years after trabeculectomy with mitomycin C (MMC). Methods A consecutive series of all 68 patients who underwent trabeculectomy with MMC was analyzed using Kaplan-Meier life-table statistics and compared with other published retrospective analyses. Results At 2- and 3-year follow-up examinations, 59% (95% confidence interval [CI], 44-70%) and 47% (95% CI, 32-61%) of patients, respectively, avoided an intraocular pressure (IOP) of more than 21 mmHg or less than 20% below their preoperative level without glaucoma medication on two consecutive occasions more than 1 month apart after 3 months follow-up (75% [95% CI, 60-84%] and 70% [95% CI, 53-81%], respectively, with medication) and avoided additional glaucoma surgery. Loss of more than three lines of visual acuity on two occasions more than 1 month apart after 3 months follow-up occurred in 28% of patients (> 2 lines in 44%) at 3 years. Nonreversible causes of loss of three lines of acuity occurred in 13% of patients. Complications requiring reoperation occurred in 16% of patients and included hypotony maculopathy (4%) and late bleb leaks (4%). Conclusions At the 3-year follow-up evaluation, trabeculectomy with MMC provided an approximately 50% chance of maintaining IOPs less than 21 mmHg and a more than 20% IOP reduction without concomitant use of glaucoma medication, which increased to 70% with the addition of medication. This procedure was associated with an approximately 30% risk of substantial visual loss (approximately 15% nonreversible) and a 15% chance of reoperation for complications.

Imaging technology has rapidly developed during the past decade, and today's practitioners are faced with an increasingly bewildering list of tests to order and machines to purchase. This text attempts to help practitioners sort out which technologies are appropriate for individual patients. The content and organization of the text have origins in the New England Eye Center's Imaging in Glaucoma: The Boston Glaucoma Course 1996. Although not a direct transcript of the course, the text is written by the speakers at that meeting. The preface indicates that the intended audience is "both general ophthalmologists and glaucoma specialists" and other eye-care professionals may also benefit. The text includes discussion of all the major imaging techniques appropriate to glaucoma. Each chapter is written by an acknowledged expert in the field, and all are well-written and concise. The book is divided into 4 major sections. The first section, "Assessing the Structure of the

The third volume of the Atlas of Ophthalmic Surgery , which includes strabismus and glaucoma, is really much more than a simple atlas. The glaucoma section includes a chapter on the anatomical principles and landmarks of glaucoma surgery; a short section regarding glaucoma laser surgery; long chapters on trabeculectomy, full-thickness filtering procedures and their complications, drainage device implantation, goniotomy, trabeculotomy, and laser therapy and cryotherapy in glaucoma; and concludes with a section on combined cataract and glaucoma surgery. I was impressed with the book from the first page of the glaucoma section. The initial page on the reader's left is solid text and the accompanying diagrams are on the right. The text is complete and concise. The diagrams are in full color, well labeled, and sufficiently detailed to provide an adequate reference for new surgeons. As in all other chapters, references are provided. Beginning with the chapter on anterior chamber angle

Few areas of ophthalmology are changing as fast as the diagnosis and treatment of glaucoma.Pharmacology of Glaucomais an update of the 1983 version, which was a summary of a meeting held to celebrate the opening of the Eye Care Centre in British Columbia. On Drance's recent retirement from heading the department there, he believed it fitting to update the information on these topics to reflect the gains in knowledge made in this field over the intervening 9 years. As such, this text is an attempt to summarize the current status of medical treatment research for glaucoma as well as to share some vision of the future and what form the next decade of advances will take. The level of the text is aimed at the basic science researcher and/or astute clinician, and clearly is not intended for those new to glaucoma. The first few chapters discuss surgical pharmacology

Over the past several decades, the practice of optometry has begun to include more diagnostic and therapeutic tools. Concurrent with this expansion of privileges is a rapid development of sophisticated diagnostic techniques and treatment modalities for glaucoma. If optometrists begin to take on more of the primary care of patients with glaucoma, members of this group may believe it necessary to educate themselves on the current state of the art. Primary Care of the Glaucomas addresses this need by proposing to help the practicing optometrist manage (or comanage) patients with glaucoma without a heavy dose of "rare, esoteric information." It is intended that "this text will serve as a silent 'colleague' for optometrists in the examination room." Chapter authors include optometrists, a PhD, and a physician. The 21 chapters are organized into three sections: "Basic Understanding," "Diagnosis," and "Treatment and Management." Basic Understanding includes chapters on definition and classification and

Recent technology has greatly affected the treatment of glaucoma. New materials for setons, antimetabolite therapies, and laser sclerostomies are being actively investigated and hold promise for improving the care of glaucomatous eyes. Similar advances in the detection of glaucomatous damage and its inevitable progression are no less exciting. Much attention has been placed on psychophysical methods of functional loss measurement, including advanced computerized perimetry techniques and contrast-sensitivity measurements. The application of the new technology to the morphological changes caused by glaucoma has also been an active area of advancement. TheOptic Nerve in Glaucomaaddresses these advances and brings the reader up to date in this important area. "... will provide the practicing generalist with all the background needed to follow future developments in this fast-improving field." The preface of the text states that its purpose is to "provide the glaucoma specialist and general ophthalmologist alike a comprehensive overview of the

Treatment of 45Ca2+-loaded GH3 pituitary cells with various concentrations of digitonin revealed discrete pools (I and II) of cellular 45Ca2+ defined by differing detergent sensitivities. Markers for cytosol and intracellular organelles indicated that the two 45Ca2+ pools were correlated with the two major cellular Ca2+-sequestering organelles, endoplasmic reticulum (I) and mitochondria (II). Studies with various inhibitors were consistent with these assignments. Mitochondrial uncouplers preferentially depleted 45Ca2+ pool II while trifluoperazine selectively depleted 45Ca2+ pool I. Control experiments indicated that translocation of in situ organellar 45Ca2+ during and after permeabilization was negligible. We used the digitonin-permeabilization method to examine the effect of thyrotropin-releasing hormone (TRH) treatment on intracellular Ca2+ pools of GH3 pituitary cells. TRH was found to rapidly deplete both endoplasmic reticulum and mitochondrial exchangeable Ca2+ by 25-30%. The 45Ca2+ loss from both pools was maximal by 1 min after TRH addition and was followed by a recovery phase; mitochondrial 45Ca2+ content returned to control levels by 30 min. Previous treatment of cells with the mitochondrial uncoupler carbonyl cyanide p-trifluoromethoxy-phenylhydrazone blocked TRH-induced 45Ca2+ efflux from mitochondria, while previous treatment with valinomycin, an agent that depleted both 45Ca2+ pools, blocked any additional effect of TRH on these pools. We conclude that TRH rapidly promotes a net loss of exchangeable Ca2+ from GH3 cells as a result of hormone-induced mobilization of Ca2+ from endoplasmic reticulum and mitochondria.