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A chronobiological study in bipolar affective disorder
111 parasympathetic blocker) totally eliminated miosis. The CPT provoked some pain with a peak of intensity during the second minute. These preliminary data suggest that CPT may induce a complex pupillary reaction which is probably linked to a sympathetic/parasympathetic activation, although the possible involvement of neuropeptides should be investigated. This model could well be a useful tool in the study of certain functional and organic diseases (cluster headache, Horner syndrome, narcolepsy etc.) which have in common an involvement of the sensory/autonomic control mechanisms.
144 Interactions Between NMDA-gated and Voltage-dependent Conductances in Nucleus Tractus Solitarii Neurons Underlie Various Discharge Patterns: a Cellular Basis for a Multifunctional Role of NTS Neurons Fabien Tell and Andr6 Jean Laboratoire de Neurophysiologie et Neurobiologie fonctionnelles, URA CNRS 205, Facult~ de Saint J&~me, 13397 Marseille Cedex 13, France The nucleus tractus solitarii (NTS) is involved in the control of numerous autonomic functions such as swallowing and breathing. The possible role of the cellular properties of NTS cells in the organization of these functions was investigated on rat brainstem slices within the medial part of the lateral NTS. Results show that activation of N M D A receptors in a same cell elicited a repetitive firing, a rhythmic bursting or a rhythmic single discharge, depending on the membrane potential. Rhythmic patterns are due to activation of endogenous properties because membrane potential oscillations were elicited by N M D A in saline that contained tetrodotoxin. The oscillations were characterized by a jump of membrane potential followed by a ramp-shaped phase that preceded spiking. In magnesium-free medium, N M D A application no longer induced oscillations indicating that their generation is based on the N M D A channel properties. Reduction of calcium influxes did not suppress NMDA-induced depolarization but eliminated endogenous oscillations. Blockade of calcium-activated potassium conductances (IKca) by apamin increased oscillation duration. Application of 4-aminopyridine that blocks the potassium A-current (IKA) altered the oscillation shape. The ramp-shaped phase was replaced by a depolarizing jump followed by a plateau phase. Results indicate that the discharge patterns are primarily due to activation of the NMDA-gated currents, calcium and potassium currents. A specific interaction between INMDAand /'KA is involved in shaping the cell's discharge and in the switch'from one rhythmic mode to the other. If these
properties are preserved in vivo they might play an important role in the organization of rhythmic activities such as swallowing and breathing. Moreover, as recently shown in invertebrates, results suggest that the function of a same neuron may be flexible. Depending on the influences it receives, a same neuron might be involved in different functions. This might provide a cellular basis for the complex physiology of the NTS.
145 Degenerative Processes in Ganglionic Neurons of the Superior Cervical Ganglion in Cisplatin-treated Rats (3. Tredici l, G. Cavaletti 2, M.G. Petruccioli l, D. Fabbrica I and G. Pizzini 1 ~Istituto di Anatomia Umana, and :Clinica Neurologica V, Universit~ di Milano, Milan and Monza, Italy Cisplatin (DDP), an effective antineoplastic drug, can induce autonomic dysfunctions. Using an experimental model of chronic D D P administration in rats we evaluated histological and ultrastructural changes induced on the sympathetic neurons of the superior cervical ganglion. In treated rats the nucleoli showed the most evident changes. They were smaller than in controls and often closely connected to the nuclear membrane. There was segregation of the granular and fibrillar components. Morphometric data confirmed a clear-cut reduction in nuclear cross-sectional area. The pathological changes observed are similar to those reported in the dorsal root ganglion neurons. In these two sites DDP can have a direct access to the nervous tissue due to the absence of an efficient blood-nerve barrier.
146 A Chronobiological Study in Bipolar Affective Disorder H. Uemura, K. Hori, K. Komori, E. Suzuki and S. Mizuno Department of Neuropsychiatry, School of Medicine, Keio University, 35 Shinanomachi Shinjuku-ku, Tokyo 160, Japan We measured plasma free and total MHPG, plasma cortisol and deep temperature for 24 hours to find differences in the relationship between the circadian rhythm of noradrenergic activity and those of other biological phenomena in five bipolar inpatients and 10 normal controls. All patients were under medication and their mood states were three depressive and two manic. Obtained data were analyzed by means of population mean-cosinor analysis. Estimated rhythm parameters
112 (mesor, amplitude, acrophase) of the two groups were compared. As a result there was significant population rhythm of plasma free and total MHPG in the controls, but not in the patients. Mesor of plasma free MHPG in the patients as a group was lower and acrophase of plasma cortisol was 2 hours earlier. All parameters of deep temperature were not different. These findings suggest that instable circadian rhythm of noradrenergic activity and stability of deep temperature rhythm and phase advance of hypothalamic-pituitary-adrenal axis may be specific in bipolar affective disorder•
147 Heart Rate Variability and Holter Recording Pitfalls P.L. Vannucchi ], S. Romano 4, L. Sabatini 2, G. Burgio 1 and C. Pelagatti 3
1Unit of Angiologic Medicine, 2Cardiology Service, 3Unit of Anaesthesiology, S.M. NuovaHospital, and 4Department of Clinical Physiopathology, University of Florence, Italy Introduction: The evaluation of 24-h heart rate variability (HRV) by Holter instruments gives very important prognostic clinical information for the patients affected by cardiac ischemic disease. The last Holter generation (Avionics Del Mar 750) has a digital output of the RR time intervals and clock hour information for disk storage and late numerical analysis. During the recording session some ECG signals are altered by a lot of disturbances and not recognised. The question arises: What happens to the R-R interval sequence in this situation? Method: We checked our Holter recordings simply grouping the R-R intervals attributed to the same clock minute by the instrument itself and checking if their total duration was summing up to one minute, within one R-R period resolution, at average. That was not always the case. Results: We compared the time plot of R-R addition within each nominal minute with the Hoiter plot of heart rate estimation (figure 1) and found that the time spans, in which R-R sums were constantly less
.
than 1 min, corresponded to periods of abnormal bradycardia. We manually observed those periods on original recordings and found very noisy ECG signal sequences. Conclusion: We suggest that underestimation of HR in the automatic digital Holter R-R output may arise in the presence of a mistake in ECG signal recognition and de-codification due to noise. We believe that a check of the sum of R-R within one minute real time is required before any kind of HRV analysis is performed.
148 Comparison of Autonomic and Somatic Nerve Fiber Regeaeratioa E. Verdfi, M. Buti and X. Navarro
Universitat Autrnoma de Barcelona, BeUaterra, Spain Functional reinnervation of sweat glands (SG), skin and muscle in the mouse paw after sciatic nerve lesions was evaluated to allow comparisons of the regeneration efficiency of autonomic and somatic nerve fibers. Unmyelinated sudomotor axons reinnervated SG from 14 days postoperation after a crush and from 25 days after a cut. The number of secreting glands, imprinted in silicone molds, increased progressively in number to a maximum of 93% and 66% of the control counts by 90 days, respectively. Positive responses to pinprick, mediated by small nociceptive fibers, were first observed in the paw at 19 days after a crush and at 26 days after a section, and were present in 100% and 95% of areas tested by 90 days. Compound muscle action potentials, evoked by stimulation of alphamotor fibers of the sciatic nerve, were recorded from plantar muscles starting 22 and 33 days postoperation in both groups of mice. The action potential amplitude increased to average values of 88% and 27% of controls by 90 days. These results indicate that, after injuries of peripheral nerves, small nerve fibers, autonomic and somatic, regenerate at a slightly faster rate and achieve a higher degree of remnervation than large myelinated fibers. 149 P a r ~ Autmmmic ~ Sensorimotor Nem'opathy with ~ i a ~ ~ ~ e f : ~ S. Watanabe t , K. Shlmazu l, T. H o s o k a w a 1, N. Tamura x, A. Kaneko t, K. HamaguehP, Y. Shimizu 2 and A. Iwasaki 2
R-R interval summed over 1 minute
1Department of Neurology and 2FirstDepartment of Pathology, Saitama Medical School, Saitama Neuropsychiatry Institute, Saitama, Japan o
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In the majority o f cases of paraneop!astic autonomic
144 Interactions Between NMDA-gated and Voltage-dependent Conductances in Nucleus Tractus Solitarii Neurons Underlie Various Discharge Patterns: a Cellular Basis for a Multifunctional Role of NTS Neurons Fabien Tell and Andr6 Jean Laboratoire de Neurophysiologie et Neurobiologie fonctionnelles, URA CNRS 205, Facult~ de Saint J&~me, 13397 Marseille Cedex 13, France The nucleus tractus solitarii (NTS) is involved in the control of numerous autonomic functions such as swallowing and breathing. The possible role of the cellular properties of NTS cells in the organization of these functions was investigated on rat brainstem slices within the medial part of the lateral NTS. Results show that activation of N M D A receptors in a same cell elicited a repetitive firing, a rhythmic bursting or a rhythmic single discharge, depending on the membrane potential. Rhythmic patterns are due to activation of endogenous properties because membrane potential oscillations were elicited by N M D A in saline that contained tetrodotoxin. The oscillations were characterized by a jump of membrane potential followed by a ramp-shaped phase that preceded spiking. In magnesium-free medium, N M D A application no longer induced oscillations indicating that their generation is based on the N M D A channel properties. Reduction of calcium influxes did not suppress NMDA-induced depolarization but eliminated endogenous oscillations. Blockade of calcium-activated potassium conductances (IKca) by apamin increased oscillation duration. Application of 4-aminopyridine that blocks the potassium A-current (IKA) altered the oscillation shape. The ramp-shaped phase was replaced by a depolarizing jump followed by a plateau phase. Results indicate that the discharge patterns are primarily due to activation of the NMDA-gated currents, calcium and potassium currents. A specific interaction between INMDAand /'KA is involved in shaping the cell's discharge and in the switch'from one rhythmic mode to the other. If these
properties are preserved in vivo they might play an important role in the organization of rhythmic activities such as swallowing and breathing. Moreover, as recently shown in invertebrates, results suggest that the function of a same neuron may be flexible. Depending on the influences it receives, a same neuron might be involved in different functions. This might provide a cellular basis for the complex physiology of the NTS.
145 Degenerative Processes in Ganglionic Neurons of the Superior Cervical Ganglion in Cisplatin-treated Rats (3. Tredici l, G. Cavaletti 2, M.G. Petruccioli l, D. Fabbrica I and G. Pizzini 1 ~Istituto di Anatomia Umana, and :Clinica Neurologica V, Universit~ di Milano, Milan and Monza, Italy Cisplatin (DDP), an effective antineoplastic drug, can induce autonomic dysfunctions. Using an experimental model of chronic D D P administration in rats we evaluated histological and ultrastructural changes induced on the sympathetic neurons of the superior cervical ganglion. In treated rats the nucleoli showed the most evident changes. They were smaller than in controls and often closely connected to the nuclear membrane. There was segregation of the granular and fibrillar components. Morphometric data confirmed a clear-cut reduction in nuclear cross-sectional area. The pathological changes observed are similar to those reported in the dorsal root ganglion neurons. In these two sites DDP can have a direct access to the nervous tissue due to the absence of an efficient blood-nerve barrier.
146 A Chronobiological Study in Bipolar Affective Disorder H. Uemura, K. Hori, K. Komori, E. Suzuki and S. Mizuno Department of Neuropsychiatry, School of Medicine, Keio University, 35 Shinanomachi Shinjuku-ku, Tokyo 160, Japan We measured plasma free and total MHPG, plasma cortisol and deep temperature for 24 hours to find differences in the relationship between the circadian rhythm of noradrenergic activity and those of other biological phenomena in five bipolar inpatients and 10 normal controls. All patients were under medication and their mood states were three depressive and two manic. Obtained data were analyzed by means of population mean-cosinor analysis. Estimated rhythm parameters
112 (mesor, amplitude, acrophase) of the two groups were compared. As a result there was significant population rhythm of plasma free and total MHPG in the controls, but not in the patients. Mesor of plasma free MHPG in the patients as a group was lower and acrophase of plasma cortisol was 2 hours earlier. All parameters of deep temperature were not different. These findings suggest that instable circadian rhythm of noradrenergic activity and stability of deep temperature rhythm and phase advance of hypothalamic-pituitary-adrenal axis may be specific in bipolar affective disorder•
147 Heart Rate Variability and Holter Recording Pitfalls P.L. Vannucchi ], S. Romano 4, L. Sabatini 2, G. Burgio 1 and C. Pelagatti 3
1Unit of Angiologic Medicine, 2Cardiology Service, 3Unit of Anaesthesiology, S.M. NuovaHospital, and 4Department of Clinical Physiopathology, University of Florence, Italy Introduction: The evaluation of 24-h heart rate variability (HRV) by Holter instruments gives very important prognostic clinical information for the patients affected by cardiac ischemic disease. The last Holter generation (Avionics Del Mar 750) has a digital output of the RR time intervals and clock hour information for disk storage and late numerical analysis. During the recording session some ECG signals are altered by a lot of disturbances and not recognised. The question arises: What happens to the R-R interval sequence in this situation? Method: We checked our Holter recordings simply grouping the R-R intervals attributed to the same clock minute by the instrument itself and checking if their total duration was summing up to one minute, within one R-R period resolution, at average. That was not always the case. Results: We compared the time plot of R-R addition within each nominal minute with the Hoiter plot of heart rate estimation (figure 1) and found that the time spans, in which R-R sums were constantly less
.
than 1 min, corresponded to periods of abnormal bradycardia. We manually observed those periods on original recordings and found very noisy ECG signal sequences. Conclusion: We suggest that underestimation of HR in the automatic digital Holter R-R output may arise in the presence of a mistake in ECG signal recognition and de-codification due to noise. We believe that a check of the sum of R-R within one minute real time is required before any kind of HRV analysis is performed.
148 Comparison of Autonomic and Somatic Nerve Fiber Regeaeratioa E. Verdfi, M. Buti and X. Navarro
Universitat Autrnoma de Barcelona, BeUaterra, Spain Functional reinnervation of sweat glands (SG), skin and muscle in the mouse paw after sciatic nerve lesions was evaluated to allow comparisons of the regeneration efficiency of autonomic and somatic nerve fibers. Unmyelinated sudomotor axons reinnervated SG from 14 days postoperation after a crush and from 25 days after a cut. The number of secreting glands, imprinted in silicone molds, increased progressively in number to a maximum of 93% and 66% of the control counts by 90 days, respectively. Positive responses to pinprick, mediated by small nociceptive fibers, were first observed in the paw at 19 days after a crush and at 26 days after a section, and were present in 100% and 95% of areas tested by 90 days. Compound muscle action potentials, evoked by stimulation of alphamotor fibers of the sciatic nerve, were recorded from plantar muscles starting 22 and 33 days postoperation in both groups of mice. The action potential amplitude increased to average values of 88% and 27% of controls by 90 days. These results indicate that, after injuries of peripheral nerves, small nerve fibers, autonomic and somatic, regenerate at a slightly faster rate and achieve a higher degree of remnervation than large myelinated fibers. 149 P a r ~ Autmmmic ~ Sensorimotor Nem'opathy with ~ i a ~ ~ ~ e f : ~ S. Watanabe t , K. Shlmazu l, T. H o s o k a w a 1, N. Tamura x, A. Kaneko t, K. HamaguehP, Y. Shimizu 2 and A. Iwasaki 2
R-R interval summed over 1 minute
1Department of Neurology and 2FirstDepartment of Pathology, Saitama Medical School, Saitama Neuropsychiatry Institute, Saitama, Japan o
•
a
•
to
•
I1 ri~a
i
I
.a
~ .4j
•
.
7
In the majority o f cases of paraneop!astic autonomic