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PubMedDate not supplied

Digital system measurement of decentration of Worst-Fechner iris claw myopia intraocular lens.

BACKGROUND: Topography measures the centration in refractive and corneal refractive surgery, but until recently there was no effective method to measure decentration in intraocular lens (IOL) implantation. PATIENTS AND METHODS: We measured the decentration of 22 phakic eyes, in 14 high myopic patients, based upon photographs of the anterior segment using a digital analysis system (IMAGEnet Topcon Corporation 1988, Tokyo, Japan). These eyes had undergone IOL implantation for the correction of myopia with Worst-Fechner iris claw lenses. Decentration was measured with respect to the centers of both the cornea and pupil. RESULTS: Mean decentration of the IOL center from the cornea center was 0.51 +/- 0.25 mm (range, 0 to 0.8374 mm). When measured with respect to the center of the pupil, the average decentration was 0.47 +/- 0.29 mm (range, 0.182 to 0.9341 mm). A positive correlation between the decentration measurements of the two methods was found (p < .01 indicated statistical significance). CONCLUSIONS: This digital imaging system (IMAGEnet) accurately measured decentration of IOLs in myopic eyes.

Adult↗
PubMed1999

[Measurement and research of posterior chamber intraocular lens tilt and decentration in vivo].

OBJECTIVE: To observe the situation of implanted lenses in vivid eyes and postoperative visual acuity affected by the lens tilt and decentration. METHODS: 64 eyes underwent extracapsular cataract extraction with posterior chamber lens implantation. Postoperatively, the lens tilt was measured by means of the 3(rd) and 4(th) Purkinje images, and the decentration of lenses was measured on the anterior segment photographs taken with a fundus camera. RESULTS: The mean tilt was (6.95 +/- 2.46) degree, and the mean decentration, (0.66 +/- 0.28) mm. There were a significant differences in the tilt and decentration between the symmetrical bag/bag and asymmetrical bag/sulcus group (P < 0.001). Bag/bag group without tear had less average decentration 0.32 mm. When tilt was more than 9.65 degrees and decentration was more than 1.02 mm, the symptom such as glare or monocular diplopia was obvious. CONCLUSIONS: These results indicate that in the bag without tear, the lenses have a perfect stability and consistent centration, and the tilt and decentration of the implanted lens affect postoperative visual quality in varying degrees.

Adult↗
PubMed1984

Medication-related nursing time in centralized and decentralized drug distribution.

The amount of time spent by nursing personnel in medication-related activities was evaluated in a centralized and a decentralized drug-distribution system. A work-sampling study was used to measure the amount of time spent by nursing personnel in various work activities before and after establishing a satellite pharmacy. Random observations of three nurses and a transcriber were made daily for five-day periods one month before and two months after the satellite pharmacy became operational. The actual number of hours worked by nursing personnel and the patient census during both study periods were also recorded. The lag time for order processing and distribution of initial doses and the accuracy of filling unit dose cassettes were measured in both drug-distribution systems. Nurses' attitudes toward the decentralized system were surveyed three months after implementation of the satellite pharmacy. The percentage of time nurses spent in medication-related activities was significantly less in the decentralized system. Actual hours spent in medication-related activities per patient day were also less in the decentralized system. Lag time for order processing decreased from 55.3 minutes in the centralized system to 15.2 minutes in the decentralized system. The number of unit dose dispensing errors per patient day also decreased after implementing the pharmacy satellite. All nurses surveyed favored the decentralized system. Decentralized drug distribution using a satellite pharmacy was associated with more efficient use of nursing time compared with centralized drug distribution.

Attitude of Health Personnel↗
PubMed1994

Decentralization and primary health care: some negative implications in developing countries.

Decentralization is a highly popular concept, being a key element of Primary Health Care policies. There are, however, certain negative implications of decentralization that must be taken into account. These are analyzed in this article with particular reference to developing countries. The authors criticize the tendency for decentralization to be associated with state limitations, and discuss the dilemma of relating decentralization, which is the enhancement of the different, to equity, which is the promotion of equivalence. Those situations in which decentralization can strengthen political domination are described. The authors conclude by setting out a checklist of warning questions and issues to be taken into account to ensure that decentralization genuinely facilitates the Primary Health Care orientation of health policy.

Developing Countries↗
PubMedDate not supplied

Decentralization and central and regional coordination of health services: the case of Switzerland.

As part of reforms in the health care delivery sector, decentralization is currently promoted in many countries as a means to improve performance and outcomes of national health care systems. Switzerland is an example of a country with a long-standing tradition of decentralized organization for many purposes, including health care delivery. Apart from the few aspects where the responsibility is at the federal level, it is the task of the 26 cantons to organize the provision of health services for the population of around 7 million people. This permits the system to be responsive to local priorities and interest as well as to new developments in medical and public health know-how. However, the increasing and complex difficulties of most health care delivery systems raise questions about the need for mechanisms for coordination at federal level, as well as about the equity and the effectiveness of the decentralized approach. The Swiss case shows that in a strongly decentralized system, health policy and strategy elaboration, as well as coordination mechanisms among the regional components of the system, are very hard to establish. This situation may lead to strong regional inequities in the financing of health care as well as to differences in the distribution of financial, human and material inputs into the health system. The study of the Swiss health system reveals also that, within a decentralized framework, the promotion of cost-effective interventions through a well-balanced approach towards promotional, preventive and curative services, or towards ambulatory and hospital care, is difficult to achieve, as agreements between relatively autonomous regions are difficult to obtain. Therefore, a decentralized system is not necessarily the most equitable and cost-effective way to deliver health care.

Efficiency, Organizational↗
PubMed1998

Causes of severe decentration and subluxation of intraocular lenses.

BACKGROUND: Severe decentration and subluxation of intraocular lenses (IOLs) may lead to double vision, glare and deterioration of vision to the point of functional aphakia. The purpose of the present study was to analyse causes for severe IOL dislocation. MATERIAL AND METHODS: Between January 1989 and January 1996, 37 patients required IOL exchange because of decentrated or subluxated posterior chamber lenses. Twenty-five of the exchanged lenses were implanted in our hospital, 12 lenses elsewhere. After explantation the lenses were examined by light and electron microscopy. RESULTS: In 10 eyes, asymmetric implantation of the posterior chamber lens was responsible for decentration. Three of the lenser concerned were multifocal IOLs. Asymmetric implantation led to a significantly higher rate of explantations in eyes with multifocal lenses (P < 0.005). In five eyes decentration developed due to asymmetric capsular shrinkage, in four eyes due to posterior synechiae. A lens subluxation developed in three eyes as a result of rupture of the posterior capsule and in nine eyes because of zonular defects. In three cases decentrations were induced by an extensive secondary cataract. Macroscopically visible changed geometry of the haptics was found in nine lenses; eight of these had polypropylene haptics. Seven lenses showed severely altered haptics on electron-microscopic examination. In four eyes subluxated lenses had to be explanted together with the capsular bag because of severe defects of the zonula, which caused decentration in nine eyes. CONCLUSIONS: Asymmetric implantation of posterior chamber lenses should be strictly avoided. Multifocal lenses require special attention concerning symmetric capsulorhexis and positioning of their haptics.

Aged↗
PubMed1995

Effects of decentralization on the levels of GAP-43 and p38 (synaptophysin) in sympathetic adrenergic neurons: a semi-quantitative study using immunofluorescence and confocal laser scanning microscopy.

The distribution of GAP-43 in superior cervical ganglion (SCG) and iris were studied in normal animals and following decentralization using immunofluorescence and confocal laser scanning microscopy (CLSM). GAP-43-like immunoreactivity (LI) was compared with p38 (synaptophysin)-LI, and tyrosin hydroxylase (TH)-LI. In the control SCG, GAP-43-LI and p38-LI were mainly localized in nerve terminals around the principal neurons. The neuronal perikarya were negative for GAP-43, but positive for p38 in a perinuclear zone, as well as positive for TH. SIF cells (Small Intensely Fluorescent cells, ganglionic interneurons) were positive for GAP-43, TH and p38. One day after decentralization, GAP-43-LI and p38-LI in nerve terminals around principal neurons had disappeared. Some of the principal neurons showed a weak GAP-43-immunoreactivity. Three days post-decentralization, GAP-43- and p38-positive nerve terminals around the neurons had reappeared in considerable numbers and the intra-ganglionic nerve bundles were positive for both antibodies. In the control irides, GAP-43-LI and p38-LI were distributed in a varicose pattern in the nerve bundles, around blood vessels and in the network of terminals. Double labelling studies showed that GAP-43-LI was colocalized with TH-LI and p38-LI. The network of terminals in the dilator plate of the irides was quantified by measuring the fluorescence intensity of randomly selected areas, using CLSM. Three days after decentralization the intensity of GAP-43-LI and p38-LI had significantly increased. TH-LI had decreased 8 days after decentralization. The results indicate that GAP-43-LI and p38-LI are normally present in the nerve fibers and terminals of both pre- and post-ganglionic neurons in adult rats. The expression of GAP-43-LI and p38-LI in post-ganglionic neurons is preganglionically regulated, as indicated by the increased expression after decentralization. The expression of p38 in these neurons is probably regulated via mechanisms that are separate from those which regulate GAP-43, since it showed a different time course than that of GAP-43-LI.

Animals↗
PubMed1993

Clinicopathologic study of the effect of radial tears and loop fixation on intraocular lens decentration.

PURPOSE: The purpose of this study is to determine the effect of loop fixation and anterior capsular tears on intraocular lens (IOL) decentration. METHODS: A retrospective measurement of IOL decentration was performed on 144 human eyes with posterior chamber (PC) IOLs obtained after death. RESULTS: Decentration in eyes with asymmetrical bag-sulcus fixation (mean +/- standard deviation, 0.64 +/- 0.39 mm) was significantly higher than eyes with symmetrical fixation. In the presence of radial tears, symmetrically fixated IOLs in either the capsular bag or the ciliary sulcus decentered to a similar degree, 0.35 +/- 0.25 mm and 0.4 +/- 0.26 mm, respectively. The least decentration was observed with capsular fixation and no radial tears (0.18 +/- 0.09 mm). This was significantly less decentration than with any other form of fixation in the presence of radial tears. CONCLUSION: This study shows that capsular fixation with no radial tears, as can be achieved by using the continuous curvilinear capsulorhexis, is associated with the least decentration.

Adult↗
PubMed1995

Relation of visual symptoms to topographic ablation zone decentration after excimer laser photorefractive keratectomy.

BACKGROUND: The authors used computer-assisted videokeratoscopy to analyze the relation of photorefractive keratectomy ablation zone decentration to subjective patient assessments of disturbing visual symptoms. METHODS: Ablation zone decentration was measured 1 month postoperatively. The study population was divided into two groups: group 1, patients whose ablation zone decentrations were less than 0.50 mm; group 2, patients whose ablation zone decentrations were greater than 0.50 mm. Visual symptoms including glare, rings or halos around lights and problems with night driving were scored preoperatively and 6 months postoperatively. The Hotelling T-square and chi-square tests were used. RESULTS: The mean decentration from the center of the ablation zone to the pupillary center was 0.30 mm and 190 degrees for group 1 compared with 0.66 mm and 198 degrees for group 2. The Hotelling T-square test showed a significant statistical preoperative/postoperative difference in group 1 (P < 0.03) for the halo symptom category. No other symptom category showed a significant statistical difference in either group for the mean scores. The Hotelling T-square test did not show a statistically significant difference between the two groups preoperatively to postoperatively regarding the mean scores of the individual patient differences for the three symptoms. The only significant statistical difference for the individual patient ratings preoperatively to postoperatively was for the halo symptom category (chi-square = 7.756; P < 0.03). CONCLUSIONS: Multivariate analysis did not show a significant statistical difference preoperatively between the two groups or postoperatively except for group 1 with regard to the halo symptom category. It appears from this study that ablation zone decentrations less than 0.89 mm from the pupillary center do not necessarily produce unwanted visual symptoms 6 months postoperatively.

Cornea↗
PubMed1995

Long-term decentration of intraocular lenses implanted with envelope capsulotomy and continuous curvilinear capsulotomy: a comparative study.

Intraocular lens (IOL) decentration was studied in a series of 569 consecutive eyes that had extracapsular cataract extraction (ECCE) and posterior chamber IOL implantation. In 383 of the eyes, an envelope capsulotomy (EC) was performed; in 186, a continuous curvilinear capsulotomy (CCC). In 33 eyes, the anterior capsule had one radial tear that reached the lens equator. In all eyes, IOL decentration was determined more than six months after surgery. Mean IOL decentration was 0.42 +/- 0.02 mm in the EC eyes and 0.27 +/- 0.01 mm in the CCC eyes (P < .001). In the CCC eyes, mean IOL decentration was 0.23 +/- 0.02 mm when the anterior capsule had no tears and 0.42 +/- 0.06 mm when it had one radial tear (P < .01). In the EC eyes, mean decentration was less with lenses with a total diameter of 11.0 mm or less and 360 degree circular loops (compressible disc and circular open-loop lenses) than with C- and J-loop lenses with a total length of 13.5 mm to 14.0 mm. With the C- and J-loop lenses in all three capsulotomy groups, mean decentration was related to the presence and number of tears in the anterior capsule: 0.58 mm in the EC eyes, 0.41 mm in the CCC with tear eyes, and 0.23 mm in the CCC without tear eyes. A similar relationship was seen with the bag-implanted lenses: 0.48 mm in the EC eyes, 0.28 mm in the CCC with tear eyes; 0.22 mm in the CCC without tear eyes.

Cataract Extraction↗
PubMed1999

Intraocular lens tilt and decentration after implantation in eyes with glaucoma.

PURPOSE: To evaluate the extent of intraocular lens (IOL) tilt and decentration after implantation in eyes with glaucoma. SETTING: Hayashi Eye Hospital, Fukuoka, Japan. METHODS: Fifty-two eyes of 52 patients with glaucoma and 52 control eyes from 52 age-matched patients had phacoemulsification with IOL implantation. Twenty-nine eyes had closed-angle glaucoma (CAG), and the other 23 eyes had open-angle glaucoma (OAG). The extent of IOL tilt and decentration was measured using Scheimpflug videophotography 1 week and 1, 3, 6, 9, and 12 months postoperatively. RESULTS: The mean tilt angle in the glaucoma group was significantly greater than in the control group throughout the follow-up. Mean decentration length was also greater in the glaucoma than in the control group, but the difference was not significant. The incidence of eyes showing a marked tilt (greater than 5 degrees) or decentration (greater than 0.5 mm) was higher in the glaucoma than in the control group. The mean tilt angle and the incidence of eyes showing a marked tilt or decentration in the CAG group were significantly greater than in the control group. CONCLUSION: Intraocular lens tilt was more extensive in the eyes with glaucoma, especially in those with CAG, than in normal eyes. Decentration was also greater in the glaucoma groups than in the control group, although the differences were not significant.

Aged↗
PubMed2002

Myocardial blood flow after chronic cardiac decentralization in anesthetized dogs: effects of ACE-inhibition.

Coronary blood flow regulation was studied in dogs with an intact or chronically decentralized intrinsic cardiac nervous system. We also examined the effect of angiotensin-converting enzyme inhibition (ACEI) on coronary autoregulatory pressure-flow relations and distribution of blood flow since the renin-angiotensin system may play a critical role in vasoregulation. Myocardial oxygen demand was reduced in the chronic decentralized dogs compared to the control dogs. The lower pressure limit of the autoregulatory pressure-flow relation was similar for the control and chronic decentralized dogs (47+/-2 and 44+/-7 mm Hg, respectively; p = NS). After ACEI, the lower pressure limit shifted leftward to 40 mm Hg (p=0.001) in both groups. Concomitant blockade of cyclooxygenase, bradykinin catabolism and nitric oxide synthase had no further effect on the lower pressure limit. Total myocardial blood flow was lower (p=0.001) in the chronic decentralized dogs compared to the control dogs, while transmural distribution of blood flow was preserved in both groups. The results show that even though myocardial oxygen requirements are lower in the chronically decentralized heart compared to controls, coronary autoregulation is maintained at levels observed in normally innervated hearts. The present findings indicate that intrinsic cardiac neurons contribute to coronary autoregulatory control and myocardial blood flow distribution even in the absence of cardiac connections to the central nervous system. In addition, in the chronic decentralized dog, ACEI allows the heart to work at lower coronary perfusion pressures while myocardial blood flow distribution is preserved.

Adrenergic beta-Antagonists↗
PubMed2000

[Decentration of donor cornea in mechanical and excimer laser trephination for penetrating keratoplasty].

BACKGROUND AND PURPOSE: Decentration of the trephination is supposed to be one of the major reasons for high and/or irregular astigmatism after penetrating keratoplasty (PK). The purpose of this study was to assess the amount and direction of donor decentration with conventional mechanical and nonmechanical laser trephination. PATIENTS AND METHODS: In this retrospective analysis 106 consecutive mechanical donor trephinations from the endothelial side (mean diameter 7.30 +/- 0.79 mm), 80 mechanical donor trephinations from the epithelial side (mean diameter 7.30 +/- 0.77 mm), and 89 nonmechanical donor trephinations from the epithelial side (Aesculap-Meditec; spot profile 1.5 x 1.5 mm, pulse energy 18-20 mJ, repetition rate 25/s) along metal aperture masks (mean diameter 7.72 +/- 0.40 mm) were included. Remaining corneoscleral rims were fixed in formalin after trephination and photographed from the endothelial side. On colour prints (13 x 18 cm; total magnification x7.33) the amount and direction of decentration were assessed morphometrically using the SummaSketch (Summagraphics, Seymour, USA) and correlated with the total area of the cornea and the trephination. RESULTS: Mean donor decentration was significantly smaller with laser trephination (0.20 +/- 0.12 mm) than with mechanical trephination from the endothelial side (0.26 +/- 0.14 mm; p = 0.001) and from the epithelial side (0.27 +/- 0.16 mm; p = 0.024). In addition, donor decentration correlated significantly inversely with the trephination area (p < 0.001), but not with the total area of the cornea (p = 0.63). A preferred direction of decentration relative to the microsurgeon could not be detected (p = 0.87). CONCLUSIONS: Centration of donor trephination can be improved by using nonmechanical instead of mechanical trephination of the cornea. Further studies are required to investigate the clinical relevance of the statistically better donor centration on astigmatism and visual acuity after PK.

Astigmatism↗
PubMed2002

Ministry of Health user fees, equity and decentralization: lessons from Honduras.

Decentralization is commonly championed as a means for achieving equity. To date, however, there has been little discussion of the mechanisms underlying this relationship, and several of the few empirical investigations that have addressed the topic have found the converse; that decentralization has exacerbated inequalities. This article examines the performance and equity in financing of the Honduras Ministry of Health's (MOH) decentralized user fee system. The MOH of Honduras established a national user fee policy in 1989. It provided a framework of rules and regulations and decentralized administration of the system to the regional offices. A survey conducted under the auspices of this study provided detailed information about the structures and operations of MOH user fee systems. The survey revealed that the systems vary markedly by region, creating horizontal inequities, and that they have numerous other shortcomings. The average price of a consultation is low, US dollars 0.16, and revenues have consistently equalled just 2% of MOH expenditures. The systems' administrative costs are equal to 67% of their revenues. Eliminating the user fee systems in all but the national and regional hospitals would actually save money and/or enable the MOH to provide more care. Average consultation prices are highest in health posts, intermediate in centres and lowest in the national hospitals, thereby encouraging the inappropriate use of the MOH's pyramidal referral system and fostering MOH inefficiency. Fee levels and exemption practices are horizontally and vertically inequitable. The likelihood of paying for an ambulatory visit is highest at a health post, 89%, and lowest at a hospital, 49%. Individuals from the poorest one-fifth of households are the most likely to have to pay for care. Honduras' experience demonstrates that a decentralized user fee system is not necessarily equitable, and that, more generally, the gains that can be realized from decentralizing user fee systems are not automatic. They must be anticipated, planned for and cultivated by a well-designed and well-implemented initiative that is not a single, one-time event, but rather a dynamic, on-going enterprise.

Ambulatory Care Facilities↗
PubMed1973

Sensitivity of the nictitating membrane of the cat to succinylcholine after decentralization and denervation.

Seven days after decentralization or denervation, the nictitating membrane of the cat becomes supersensitive to succinylcholine. The supersensitivity to succinylcholine is of a moderate degree (2-3 fold) and there is little difference between the supersensitivity induced by decentralization or denervation. In this respect, it is similar to the decentralization type of supersensitivity observed for other agonists which are not taken up by the adrenergic nerve endings (e.g. acetylcholine and methoxamine). Since succinyloholine causes an apparent contraction of the nictitating membrane through its action on the extraocular muscle and no effect on the nictitating membrane itself, it is concluded that both chronic decentralization and denervation produced a decentralization type supersensitivity in the extraocular muscles. The results suggest that supersensitivity in the extraocular muscles may contribute significantly to the decentralization supersensitivity of the nictitating membrane of the cat, in vivo, especially for those agonists which cause contractions of both the nictitating membrane and the extraocular muscle.

Animals↗
PubMed1984

Functional evidence for sprouting or decentralized parasympathetic neurons in rat urinary bladder.

The pelvic nerve, carrying parasympathetic nerve fibres, distributes bilaterally in the rat urinary bladder. Preganglionic parasympathetic denervation (decentralization) on one side and postganglionic parasympathetic denervation on the other are followed by an initial decrease in acetylcholine forming capacity and in number of acetylcholinesterase positive nerves in the bladder. However, within a few weeks a marked recovery in acetylcholine synthesis and in number of nerves, based on collateral sprouting, occurs. In this study muscle strips of the rat urinary bladder exposed to the combined surgical procedure was studied. The strips were taken from "denervated" and "decentralized" halves of the bladder. Their contractile responses to methacholine and transmural electrical field stimulation were isometrically recorded in vitro. A supersensitivity to methacholine was found to have developed, of about the same degree, in the two halves 1 week postoperatively. In the denervated halves 4 weeks postoperatively, the supersensitivity was even more marked, whereas in the decentralized halves it tended to be less than after 1 week. The responses of denervated halves to electrical stimulation were reduced 1 week postoperatively. This was also the case for decentralized halves, although the reduction was not large enough to be significant. When examined 4 weeks postoperatively the responses, in particular in denervated halves, were enlarged compared to those 1 week postoperatively. The atropine-sensitive portion of the responses increased with time. Increases in contractile responses to electrical stimulation accompanied by a tendency to desensitization to methacholine are taken as functional evidence for outgrowth of decentralized parasympathetic neurones in the decentralized halves.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed2004

Chronic decentralization potentiates neurovascular transmission in the isolated rat tail artery, mimicking the effects of spinal transection.

Spinal cord transection produces a marked increase in the response of the isolated rat tail artery to sympathetic nerve stimulation, possibly as a result of a decrease in ongoing sympathetic activity. We have tested the effects of removing ongoing nerve activity on neurovascular transmission by cutting the preganglionic input to postganglionic neurones supplying the tail artery (decentralization). Isometric contractions to nerve stimulation were compared between decentralized arteries and those from age-matched and sham-operated controls. Nerve-evoked responses of decentralized arteries were much larger than those of control arteries at 2 and 7 weeks post operatively. The extent of blockade of nerve-evoked contraction by alpha-adrenoceptor antagonists prazosin (10 nM) or idazoxan (0.1 microM) was reduced. Decentralized arteries were transiently supersensitive to the alpha1-adrenoceptor agonist phenylephrine and the alpha2-adrenoceptor agonist clonidine; the unchanged sensitivity to methoxamine and phenylephrine after 2 weeks indicated no effect on the neuronal noradrenaline uptake transporter. Decentralized arteries were hypersensitive to alpha,beta methylene-ATP, but the P2-purinoceptor antagonist suramin (0.1 mM) did not reduce nerve-evoked contractions. Enlarged responses to 60 mM K+ after both 2 and 7 weeks were correlated with the response of the arteries to nerve stimulation, suggesting that increased postjunctional reactivity contributes to the enhanced contraction. Comparison between data from decentralized arteries and our previous data from spinalized animals showed that the two lesions similarly potentiate nerve-evoked contractions and have similar but not identical postjunctional effects. The enhanced vascular responses following a reduction in tonic nerve activity may contribute to the hypertensive episodes of autonomic dysreflexia in spinally injured patients.

Animals↗
PubMed2001

Chronic decentralization of the heart differentially remodels canine intrinsic cardiac neuron muscarinic receptors.

The objective of the study was to determine if chronic interruption of all extrinsic nerve inputs to the heart alters cholinergic-mediated responses within the intrinsic cardiac nervous system (ICN). Extracardiac nerve inputs to the ICN were surgically interrupted (ICN decentralized). Three weeks later, the intrinsic cardiac right atrial ganglionated plexus (RAGP) was removed and intrinsic cardiac neuronal responses were evaluated electrophysiologically. Cholinergic receptor abundance was evaluated using autoradiography. In sham controls and chronic decentralized ICN ganglia, neuronal postsynaptic responses were mediated by acetylcholine, acting at nicotinic and muscarinic receptors. Muscarine- but not nicotine-mediated synaptic responses that were enhanced after chronic ICN decentralization. After chronic decentralization, muscarine facilitation of orthodromic neuronal activation increased. Receptor autoradiography demonstrated that nicotinic and muscarinic receptor density associated with the RAGP was unaffected by decentralization and that muscarinic receptors were tenfold more abundant than nicotinic receptors in the right atrial ganglia in each group. After chronic decentralization of the ICN, intrinsic cardiac neurons remain viable and responsive to cholinergic synaptic inputs. Enhanced muscarinic responsiveness of intrinsic cardiac neurons occurs without changes in receptor abundance.

Acetylcholine↗