Cardiac dysrhythmias in the conscious dog after surgically induced autonomic imbalance.

The ventrolateral cardiac nerve in the dog is a primary branch of the left sympathetics and represents a direct neural link between the central nervous system and the heart. Its electric excitation elicits characteristic shifts in pacemaker and tachydysrhythmias related to its explicit innervation of the inferior atrial, atrioventricular (A-V) junctional and ventricular tissues. Total denervation of the canine heart, sparing the ventrolateral cardiac nerve, produced a long-term model in which only these portions of the heart retained their sympathetic innervation. The trained unanesthetized model dog was subjected to severe exercise in order to determine the effects of elevated levels of sympathetic tone upon these important regions of the conduction system. Reproducible tachydysrhythmias were elicited in all six animals completing the regimen of periodic testing over a period of 136 to 378 days after operation. The abnormal rhythms consisted of shifting cardiac pacemakers and supraventricular A-V junctional and ventricular tachycardias with frequent premature systoles. Comparable abnormalities were not observed in a similarly tested sham-operated animal or in dogs with a totally denervated heart. The exercise-induced dysrhythmias gradually disappeared with time, presumably in relation to autonomic reinnervation of the heart. The characteristic patterns of ventrolateral cardiac nerve and upon its presumed influence upon Purkinje fiber and A-V nodal automaticity and temporal dispersion of refractoriness in myocardial tissues.

Cryosurgery on postganglionic fibers (posterior nasal branches) of the pterygopalatine ganglion for vasomotor rhinitis.

Clinical experience with a newly designed device for cryosurgery on autonomic nerves in cases of vasomotor rhinitis is reported. The device consists of a handy spray of liquid nitrogen and a slender probe 2.5 mm in diameter. The posterior nasal branches of the pterygopalatine ganglion were destructed by freezing for 5-8 sec with a jet of supercooled nitrogen gas delivered onto the pterygopalatine foramen under anesthesia with 4% lidocaine. Satisfactory results were obtained by this procedure in 77 of 102 cases of vasomotor rhinitis which had failed to respond to antihistaminics. This original technique of cryosurgery which is not time-consuming and can be performed on an ambulatory basis will prove useful in clinical practice.

Cytologic alterations in nasal mucosa after sphenopalatine artery ligation in patients with vasomotor rhinitis.

BACKGROUND: Vasomotor rhinitis (VR) seems to be related to an imbalance between cholinergic and adrenergic activity in the autonomic nervous system. The nerve fibers of the sympathetic and parasympathetic nervous systems reach the nose through the posterior nasal nerve, which, after crossing the sphenopalatine foramen, distributes to the mucosa following the branches of the sphenopalatine vessels. This study was designed to evaluate the effect of sphenopalatine artery ligation on nasal function and nasal cytology in patients with VR. METHODS: Thirty patients with VR and bilateral inferior turbinate hypertrophy (ITH) were randomly assigned to receive endoscopic inferior turbinoplasty either with or without sphenopalatine artery ligation. Pre- (baseline) and postsurgical (1-year follow-up) assessment included fiber endoscopy, active anterior rhinomanometry, measurement of mucociliary transport time (MTt), and nasal cytology examination. RESULTS: At 1-year follow-up there was a statistically significant improvement in nasal resistances in both groups but not on intergroup comparison; MTt significantly decreased in both groups (p < 0.01) and was significantly better (p < 0.05) in the group that had undergone sphenopalatine artery ligation. Among the patients in this group, significantly fewer were found to have altered ciliated cells (p < 0.005) or a hyperchromatic supranuclear stria (p < 0.005) on nasal cytology; the differences were statistically significant also on intergroup comparison (p < 0.005 and p < 0.001, respectively). CONCLUSION: In patients with vasomotor rhinopathy and ITH, improvement in symptoms, nasal resistance, ciliated cell trophism, and MTt was observed after sphenopalatine artery ligation.

Gender difference in a subpopulation of rat superior cervical ganglion neurons.

The number of superior cervical ganglion (SCG) neurons is equivalent in males and females on the day of birth. By 15 days, after most of the normal neuron death has occurred, males have 20-30% more neurons than females; and this difference persists in the adult. The present study was undertaken to determine whether this difference exists uniformly throughout the ganglion, or only in a subpopulation of these neurons. To study subpopulations of SCG neurons, bilateral transection of the internal carotid nerve, the external carotid nerve, or both postganglionic nerves was performed on neonatal male and female Sprague-Dawley rats on the day of birth. Littermate sham operates served as controls. Numbers of neurons were counted in SCGs of animals on either postnatal day 4 or 15, before or after normal development of the SCG sex difference. At 4 days, the number of SCG neurons in sham-operated males had females were not different, while at 15 days, sham-operated males had more SCG neurons than did sham-operated females. The number of neurons remaining in the SCG following neonatal transection of the internal carotid nerve were not different in males and females at either 4 or 15 days postnatal. The number of SCG neurons remaining following neonatal transection of the external carotid nerve was greater in males than in females at both 4 and 15 days postnatal. It was concluded that the gender difference in survival of SCG neurons lies in neurons projecting through the internal carotid nerve. The number of neurons projecting out the external carotid nerve is equivalent in males and females.

[Molecular forms of acetylcholinesterase in the chicken ciliary ganglion; changes after denervation, axotomy and double section]. / Formes moléculaires de l'acétylcholinestérase dans le ganglion ciliaire du Poulet; évolution après dénervation, axotomie et double section.

Four main molecular forms of acetylcholinesterase (AChE), with sedimentation coefficients of 5, 7.5, 11.5 and 20 S, are found in Chicken ciliary ganglion. After denervation, the loss in 11.5 and 20 S forms occuring in 48 hrs coincides with the disappearance of presynaptic structures. In contrast, axotomy induces an early and durable increase in 7.5 S form. From these results, it is inferred that 11.5 and 20 S forms are predominant in presynaptic structures and 7.5 S form is mainly postsynaptic. In addition, the effects observed after simultaneous denervation and axotomy show a reciprocal control between pre- and postsynaptic elements. Finally, a trans-synaptic effect is exerted on 20 S AChE in controlateral ganglion after preganglionic sections.

Effect of early postnatal division of the postganglionic nerves on the development of principal cells and small intensely fluorescent cells in the rat superior cervical ganglion.

The three main postganglionic nerve branches of the superior cervical ganglion were divided on one side in 3--4-day-old rats. Five, 10, 20 and 60 days after the operation, the number of principal cells and small intensely fluorescent (SIF) cells, and the ganglion volume were estimated from a complete series of sections through each ganglion, in which catecholamines were histochemically demonstrated by formaldehyde-induced fluorescence. As compared with the contralateral, intact ganglion, the operated ganglion showed a rapid loss of principal cell bodies to about 1/20th of the control value, and the normally large postnatal increase in the volume of the ganglion failed to take place in the operated ganglion. Sham operation experiments showed that these changes were due to nerve division rather than disturbed blood supply and manipulation. The number of SIF cells increased in the intact ganglia from about 200 cells/ganglion at birth and reached the adult value, about 600 cells/ganglion by the 23rd postnatal day. An essentially similar postnatal increase in Sif cell number occurred in the experimental ganglia in spite of the marked loss of principal cells. The relative number of SIF cells increased from less than 1% of all cells (SIF cells and principal cells) in the control ganglia to over 10% in the operated ganglia, in which large aggregates of SIF cells formed 20 and 60 days after nerve division. It is concluded that different sets of developmental rules may apply to the SIF cells and the principal cells.

Effects of pre-ganglionic decentralization or post-ganglionic excision of the superior cervical ganglia on brain edema and heat stroke in rats.

The preventive effect of pre-ganglionic decentralization (Sympathetic trunk resectioN) or postganglionic excision (ganglionectomy) of the superior cervical ganglia on thermal injury induced brain edema or the development of heat stroke was assessed in rats. Brain edema was induced by cold or heat injury to the cortex in 24 rats. The results showed that decentralization, but not excision, of the superior cervical ganglia greatly inhibited the formation of brain edema which was subsequently induced. When heat stroke was induced by exposing 24 rats to an ambient temperature of 41 degree C, the latency for the onset of the heat stroke and the survival time after the heat stroke were greatly prolonged by the former surgical procedure, but shortened by the later one. The present study demonstrates the potential benefit to brain edema and heat stroke of the pretreatment with decentralization of the superior cervical ganglia.