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PubMed1994

A comparison between the adult rat and neonate rat of the architecture of sympathetic preganglionic neurones projecting to the superior cervical ganglion, stellate ganglion and adrenal medulla.

Sympathetic preganglionic neurones (SPN) projecting to the superior cervical ganglion (SCG) and adrenal medulla (AM) in the neonate (< 14 days) and SCG, stellate ganglion (SG) and AM in the adult rat (> 3 months) were retrogradely labelled with cholera B horseradish peroxidase (CBHRP). Labelled neurones were found in 4 four distinct nuclei: the nucleus intermediolateralis thoracolumbalis pars principalis (ILp), a nucleus equivalent to the intemediolateral cell column (IML); the nucleus intermediolateralis thoracolumbalis pars funicularis (ILf); the nucleus intercalatus spinalis (IC) and the nucleus intercalatus pars paraependymatis (ICpe) or central autonomic area (CA). These were represented to a similar extent in both neonate and adult. Neonate and adult SCG, SG and AM-SPN had a similar segmental distribution cervical 8 (C8) to thoracic 5 (T5) for SCG-SPN and thoracic 3 (T3) to thoracic (T13) for AM-SPN whereas adult SG-SPN were distributed over segments C8 to T9. Most labelled neurones (70%) were located in the ILp with one segment containing the highest proportion of SPN. Three morphologically distinct neurones were evident. Fusiform and roundbodied were the most common. Fusiform somata of the ILp were orientated both mediolaterally and rostrocaudally in the neonate but only rostrocaudally in the adult. Dendrites of the SPN in the adult and neonate extended in a dense rostrocaudal band along the ILp, more diffusely into the white matter of the Ilf and in bundles medially towards the central canal (CC). The neonate showed some significant differences. In the ILp, the cell bodies were less tightly packed into a narrow band and into clusters and the dendrites were more diffuse. It was concluded that at 12 days postnatally the organisation of the sympathetic nuclei had still nor reached the adult form. However, there is no extensive realignment of dendrites in the adult so the ILp remains an 'open' nucleus like the neonate.

Adrenal Medulla↗
PubMed1996

Can the neurotrophic hypothesis explain degeneration and loss of plasticity in mature and ageing autonomic nerves?

The causes of age-related degeneration in the peripheral nervous system remain unclear. The search for clues has focused on developmental mechanisms and particularly on the neurotrophic hypothesis and its principal player, nerve growth factor, reduced levels of which are thought to cause degeneration of some autonomic and central neurons in old age. Nerve growth factor may well be important in the mature and ageing nervous system, but recent experiments on sympathetic nerves in ageing rats suggest that lack of NGF is not the only limiting factor in neuronal growth and survival. Other candidates include laminin, which is bound in the extracellular matrix and may act in synergy with NGF to regulate neuronal maintenance and growth in maturity. Reduced, region-specific patterns of availability of one or both of these substances may underlie age-related degeneration in autonomic nerves. Different combinations of these factors may influence particular aspects of neuronal plasticity, such as collateral sprouting and regeneration. In addition to extrinsic factors, it appears increasingly likely that altered neuronal responsiveness to neurotrophic factors in old age contributes to structural and functional deficits in autonomic nerves.

Aging↗
PubMed1996

Power spectral analysis of heart-rate variability reflects the level of cardiac autonomic activity in rabbits.

Power spectral analysis of heart rate (HR) variability was tested in conscious rabbits to assess the reliability of this method for assessing cardiac autonomic function in normal rabbits under resting conditions. Evaluation of power spectrum was performed in 5 rabbits under normal resting conditions and after sympathetic, parasympathetic and combined sympathetic plus parasympathetic blockade. Rabbits were randomly assigned to undergo sympathetic (propranolol) or parasympathetic (methscopolamine) blockade at the initial step followed by combined blockade. The power spectrum of heart-rate variability in rabbits was presented as one broad spectral component at frequencies mainly between 0 and 0.5 Hz. This component was considerably modulated by both sympathetic and parasympathetic influences with substantial overlap of sympathetic- and parasympathetic-related components of the spectrogram. Nevertheless, it was clearly shown that power of heart-rate variability at frequencies from 0.4373 Hz to 0.5625 Hz was determined only by parasympathetic influences, and sympathetic modulation of HR was presented mainly at frequencies from 0.0625 Hz to 0.1875 Hz. Spectral subcomponent analysis of the power spectrum of HR variability may be useful to follow changes in cardiac autonomic function in rabbits.

Adrenergic beta-Antagonists↗
PubMed1996

Acrylamide-induced neuropathic changes in rat enteric nerves: similarities with effects of streptozotocin-diabetes.

The effect of acrylamide intoxication (a widely used model for autonomic neuropathy) on the fluorescence intensity and density of catecholamine- and peptide-containing nerve fibres and tissue content of noradrenaline and the peptides vasoactive intestinal polypeptide, calcitonin gene-related peptide, substance P and neuropeptide Y in the enteric nerves of rat ileum was examined. Histochemical and immunohistochemical techniques were used to localize catecholamine- and peptide-containing nerve fibres. The tissue content of noradrenaline was measured using high-performance liquid chromatography, and an enzyme-linked immunosorbent assay technique was used to determine the tissue content of the peptides investigated. Acrylamide intoxication caused a significant decrease in the density of catecholamine-containing nerve fibres and tissue content of noradrenaline in the myenteric plexus of rat ileum. A decrease in tissue content and immunoreactivity of calcitonin gene-related peptide and an increase in vasoactive intestinal polypeptide was seen in the myenteric plexus of ileum from acrylamide-intoxicated rats. In the submucous plexus, the acrylamide treatment caused a decrease in calcitonin gene-related peptide immunoreactivity and an increase in vasoactive intestinal polypeptide and neuropeptide Y immunoreactivity. There was no change in either tissue content or immunoreactivity of substance P in both myenteric and submucous plexuses of the treated rat ileum. These changes have a striking similarity with those found in the enteric nerves of streptozotocin-diabetic rat ileum, suggesting the possible presence of an underlying common mechanism(s) in the development of neuropathic changes in the autonomic nerves of acrylamide-intoxicated and streptozotocin-diabetic rats.

Acrylamide↗
PubMed1996

Localization of nicotinamide adenine dinucleotide phosphate diaphorase (NADPH-d) activity in the gastrointestinal sphincters in the guinea pig.

The distribution of nicotinamide adenine dinucleotide phosphate-diaphorase (NADPH-d), a marker for nitric oxide synthase (NOS), in the nerves of gastrointestinal sphincters in guinea pigs was investigated to throw some light on the role of nitric oxide (NO) in these sphincteric regions. The nerve fibres with NADPH-d activity were observed chiefly in the circular muscle layer of the wall of gastrointestinal sphincters. Compared with the adjacent non-sphincteric regions, the proportions of NADPH-d positive myenteric neurons in the lower esophageal sphincter (LES), pyloric sphincter (PS) and internal anal sphincter (IAS) were higher (P < 0.05). The densities of NADPH-d-positive fibres in the circular muscle of above sphincteric regions were also higher (in LES P < 0.01; in PS and IAS P < 0.05). Within the circular muscle of LES, some discrete NADPH-d-positive intrinsic nerve cell bodies, usually smaller than their outlying myenteric neurons, were also observed. The dense distribution of NADPH-d-positive fibres within the circular muscles of gastrointestinal sphincteric regions suggests that NO, as a non-adrenergic non-cholinergic (NANC) inhibitory neurotransmitter, might play an important role in the neuronal regulation of the guinea-pig gastrointestinal sphincters.

Animals↗
PubMed1996

Isolation of synaptosomes from the rat urinary bladder.

Synaptosomes are nerve-end particles (NEP) isolated by using the technique of differential centrifugation. The synaptosome offers a good model for biochemical and pharmacological studies of the nerve endings. No report has been made on synaptosome isolation from the urinary bladder. The purpose of our work was to develop the use of synaptosome in the research of neurophysiology and neuropharmacology of the urinary bladder. Synaptosome-rich fraction was prepared from tissue homogenate of male Wistar rat urinary bladder by differential centrifugation (1000, 17,000 and 100,000 g) with discontinuous sucrose gradient. Electron microscopy showed synaptosomes as thin-walled bags containing a large number of synaptic vesicles. Two types of synaptosomes were easily discerned: those containing small agranular vesicles, and those containing dense-cored vesicles. The acetylcholine, norepinephrine, epinephrine and dopamine contents in the preparation were measured by the method of high-performance liquid chromatography. The respective concentrations were 300.4 +/- 30.1, 962.8 +/- 58.5, 617.3 +/- 59.8 and 1354.8 +/- 144.2 pmol/mg synaptosomal protein. In conclusion, it has been demonstrated that synaptosome-rich fractions can be prepared from the rat urinary bladder. Thus it is possible to apply this methodology for the investigation of the neurobiology of urinary bladders.

Animals↗
PubMed1996

Effect of metoclopramide on muscle sympathetic nerve activity in humans.

The aim of this study was to determine the effect of metoclopramide on the sympathetic nervous system. Muscle sympathetic nerve activity was increased in two stages after metoclopramide injection. The initial increase in sympathetic nerve activity may result from the unloading of arterial baroreceptors because there was a negative correlation between mean blood pressure and muscle sympathetic nerve activity. The later increase in muscle sympathetic nerve activity may be attributed to the central activation of the sympathetic nervous system because there was a positive correlation between mean blood pressure and muscle sympathetic nerve activity. These results suggest that metoclopramide activates the sympathetic nervous system by two different mechanisms.

Adrenergic Fibers↗
PubMed1996

Myenteric neurons with different projections have different dendritic tree patterns: a morphometric study in the pig ileum.

Morphometric analysis was performed of two types of myenteric neurons with at first glance, very similar morphology, but different projections in the pig ileum. 50 type IV cells projecting vertically to the outer submucosal plexus, and 50 solitary type V neurons projecting aborally, within the myenteric plexus, were evaluated. Using a computer-aided morphometric device, the following parameters were recorded: somal area, longest somal diameter, number of primary dendrites, dendritic length, number of dendritic branching points and number of terminal segments. In addition to other significant differences, the most prominent discriminating parameter between the two populations of nerve cells estimated in this study was the length of the longest dendrite of each cell type. The longest dendrite of an individual type V neuron is a manifold longer than the corresponding somal diameter, in contrast to type IV neurons where it is at most twice the somal diameter. In addition, all type IV and type V single dendritic lengths were arranged in histogramms, where the type V dendrites showed two frequency peaks. Thus, we assume that solitary type V neurons can develop two populations of dendrites: a short and a long one. These results demonstrate that myenteric neurons with different projections (and hence different functions) display strikingly different dendritic morphology.

Animals↗
PubMed1996

Non-noradrenergic sympathetic neurons project to extramuscular feed arteries and proximal intramuscular arteries of skeletal muscles in guinea-pig hindlimbs.

This study set out to examine the non-noradrenergic sympathetic innervation of extramuscular and intramuscular arterial vessels supplying hindlimb muscles of guinea-pigs, using multiple-labelling fluorescence immunohistochemistry. Non-noradrenergic axons, identified by their immunoreactivity (IR) to vasoactive intestinal peptide (VIP) and neuropeptide Y (NPY), innervated nearly all (> or = 88%) extramuscular feed arteries supplying muscles of the medial thigh. The distribution of non-noradrenergic axons along extramuscular feed arteries was often patchy, with increased density near some branch points. The density of axons with VIP-IR and NPY-IR at the adventitia-medial junction of the largest extramuscular arteries was similar to the density of noradrenergic axons identified by IR to tyrosine hydroxylase (TH) and NPY. The proportion of arterial vessels innervated by VIP-IR axons decreased in more distal, intramuscular arterial segments, and when present, the VIP-IR axons were fewer in number than TH-IR axons innervating the same segments. Distal arterioles (< 20 microns diameter) were never innervated by VIP-IR axons, but always by TH-Ir axons. The non-noradrenergic sympathetic neurons are almost certainly vasodilator neurons. The prominent innervation of extramuscular feed arteries by sympathetic non-noradrenergic neurons has not been reported previously, even in cats and dogs where there is good physiological evidence for a sympathetic vasodilator response in skeletal muscles. The present morphological results provide compelling reasons for re-evaluating the functional role of sympathetic vasodilation in skeletal muscles of rodents, particularly in relation to the role of feed arteries in neural regulation of muscle blood flow.

Animals↗
PubMed1996

Immunohistochemical characterisation of viscerofugal neurons projecting to the inferior mesenteric and major pelvic ganglia in the male rat.

Viscerofugal neurons in the myenteric plexus project out of the gut to the sympathetic neurons of the prevertebral ganglia and form the afferent arm of the intestino-intestinal inhibitory reflexes. In this study, we retrogradely labelled viscerofugal neurons in the middle and distal colon, and rectum which project to or through the inferior mesenteric ganglion and major pelvic ganglia. We found that 57-81% of these neurons contained immunoreactivity to calbindin, 37-70% contained immunoreactivity to bombesin, and 22-37% contained immunoreactivity to nitric oxide synthase, irrespective of the ganglion to which they projected. However, only 0-12% of viscerofugal neurons labelled in the rectum from the inferior mesenteric ganglion or intermesenteric nerves contained immunoreactivity to vasoactive intestinal peptide (VIP). In contrast, about 45% of viscerofugal neurons labelled from the pelvic ganglia contained VIP. We also have utilised immunoreactivity to bombesin to demonstrate, for the first time, the presence of viscerofugal terminals surrounding some sympathetic neurons in the major pelvic ganglia. The enteric origin of these terminals was confirmed by their degeneration following severance of the connections between the pelvic ganglia and the lower bowel. Our observation that some pelvic neurons receive viscerofugal input suggests that they can integrate peripheral and central messages. However, the majority of pelvic neurons do not receive viscerofugal input and would be predicted simply to relay central messages.

Animals↗
PubMed1996

Projections of neurons in the intestinal nerve of Remak to the chicken intestine.

To date, the exact site of the extrinsic postganglionic neurons innervating the intramural plexuses in the chicken intestine is unknown. In this study, neurons in the intestinal nerve of Remak (INR) were immunohistochemically labelled by injecting cholera toxin subunit B (CTb) into each one of the jejunal, ileal, cecal and rectal walls. The CTb-immunoreactive (IR) neurons were counted, and some sections from the rectal portion of INR (rectal INR) were also immunostained for either tyrosine hydroxylase (TH) or methionine enkephalin (mENK). Following injection of CTb into the jejunum or ileum, only a few CTb-IR neurons were found in the jejunal or ileal part of INR caudal to the injection site. Following injection into the more caudal intestine, CTb-IR neurons were seen in the rectal INR. Of the 3490 CTb-IR neurons that were counted in the rectal INR, 40% projected into the rostral rectum, 24% into the caudal rectum, 17% into the ileum, 10% into the cecum and only 9% into the middle rectum. Rostrocaudally dividing the rectal INR into three parts, one third of the CTb-IR neurons in the rostral part projected into the rostral rectum, the majority of CTb-IR ones in the middle part innervated the rostral rectum, and half of CTb-IR neurons in the caudal part ran into the caudal rectum. Consequently, the rostral rectum received the densest innervation, and almost all the neurons in the rectal INR exhibited an ascending projection. By double labelling, CTb-IR neurons containing TH or mENK were observed in the rectal INR after the rectal injection. The mENK-IR neurons localized in middle and caudal parts of rectal INR amounted to one third of the total CTb-IR neurons, and mainly projected into the rostral and caudal rectum. TH-and mENK-immunonegative neurons were restricted to the rostral part of rectal INR and the more rostral level.

Animals↗
PubMed1988

Multiple neuropeptides in nerves supplying mammalian lymph nodes: messenger candidates for sensory and autonomic neuroimmunomodulation?

By the use of light microscopic (LM) immunohistochemistry, the presence of peptides and of dopamine beta-hydroxylase (DBH) in nerves supplying mammalian (guinea pig, rat, cat, pig, mouse, human) lymph nodes were examined. In all species, lymph nodes of various somatic and visceral regions were found to contain nerve fibers which stained for neuropeptide Y (NPY), vasoactive intestinal polypeptide (VIP), peptide histidine isoleucine (PHI), substance P (SP), calcitonin gene-related peptide (CGRP) or DBH. SP- and CGRP-immunoreactive (ir) fibers completely overlapped and exhibited the widest distribution. They were present in perivascular, paravascular and many non-vascular fibers travelling in close contact with lymphoid cells. In contrast, NPY-ir fibers coincided with those staining for DBH, prevailed in perivascular plexus and only rarely branched off into lymphoid parenchyma. Alternate staining of adjacent sections revealed that SP/CGRP-ir fibers were different from NPY/DBH-ir fibers. The distribution of VIP-ir fibers was identical to that of PHI-ir fibers and partially overlapped with that of ir-NPY/DBH or ir-SP/CGRP fibers. We conclude that the NPY innervation of lymph nodes is sympathetic noradrenergic while nerves coding for co-existing SP and CGRP are most likely of sensory origin. The nerves containing co-existing VIP and PHI may be of heterogenous origin (sensory, cholinergic sympathetic, and/or parasympathetic). We suggest that these distinct sensory and autonomic peptidergic pathways linking the nervous system with the lymph nodes may play a differential role in bidirectional neuroimmunomodulation.

Adrenergic Fibers↗
PubMed1994

Noxious distention of viscera results in differential c-Fos expression in second order sensory neurons receiving 'sympathetic' or 'parasympathetic' input.

Visceral organs receive dual innervation from primary afferents commonly referred to as 'sympathetic' and 'parasympathetic' afferents. We have previously reported a significantly greater induction of immediate-early genes in the viscerotopically appropriate spinal cord segments receiving 'parasympathetic' afferent innervation (pelvic nerve) compared with those receiving 'sympathetic' afferent innervation (hypogastric nerve) following noxious colorectal distention. In this study, the nucleus of the solitary tract (NTS) and viscerotopically appropriate spinal cord segments were labeled immunocytochemically for c-Fos following noxious gastric or esophageal distention to determine if the differential labeling following 'sympathetic' (spinal) and 'parasympathetic' (vagal) visceral afferent input is a general phenomenon of the gastrointestinal tract. Gastric distention and esophageal distention induced considerable c-Fos in the NTS and virtually none in the thoracic spinal segments. These data suggest that 'parasympathetic' visceral afferents may be different than 'sympathetic' visceral afferents with respect to their ability to induce c-Fos following noxious visceral distention.

Animals↗
PubMed1996

Hypothalamic neuron projection to autonomic preganglionic levels related with glucose metabolism: a fluorescent labelling study in the rat.

The location of hypothalamic paraventricular neurons projecting to sympathetic preganglionic levels and related to the autonomic regulation of various organs involved in glucose metabolism (OGM) was determined by ipsilateral injections of two fluorescent tracers, Diamidino Yellow into the left dorsal motor nucleus of the vagus and Fast Blue into the left intermediolateral cell column of the T8-T9 spinal cord. Hypothalamospinal neurons were mainly located in the dorsal part of the paraventricular hypothalamic nucleus (PVH) and the hypothalamobulbar neurons were most abundant in the ventral, medial and extreme lateral parts of the PVH. No double-labelled neurons were found in the hypothalamus. These results can help the knowledge of the neural hypothalamic network related with the autonomic hypothalamic control.

Animals↗
PubMed1996

Functional properties of postganglionic sympathetic neurones supplying the submandibular gland in the anaesthetized rat.

Sympathetic neurones supplying the submandibular salivary gland innervate blood vessels, secretory and myoepithelial cells. Here we examined whether these functionally different sympathetic neurones show distinct reflex response patterns. In anaesthetized rats, single unit activity was recorded from postganglionic axons projecting to the gland. Neurones were tested for their responses to stimulation of baroreceptors, cutaneous nociceptors and cold receptors and to gustatory stimuli applied to the tongue. Respiratory modulation was also analysed. Only a few postganglionic neurones identified electrically (5-10%) were spontaneously active. They were excited by noxious and cold stimuli, inhibited by baroreceptor stimulation and exhibited respiratory modulation. None of the units responded to gustatory stimuli. Thus, in anaesthetized rats spontaneously active sympathetic neurones supplying the submandibular gland behave like vasoconstrictor neurones. Sympathetic neurones with other functions are probably silent.

Anesthesia, General↗
PubMed1985

Spatial summation of pre-pain and pain in human teeth.

The purpose of this work was to investigate the relation between the sensations of pain and 'pre-pain' evoked by stimulation of teeth in human subjects. Electrical pulses of progressively increasing amplitude, generated by a computer-controlled stimulator, were applied to 1 or 2 teeth, and the subjects responded by indicating the nature of the resulting sensation. Pre-pain and pain could be readily and rapidly distinguished by all 11 subjects (response latency about 0.4 sec). Both sensations had stable thresholds with relatively small variance (S.D. 10-15% of threshold value) for a given subject. Subjects characterized the stimuli as indifferent or unpleasant, localized, and brief. By using special stimulation strategies (termed 'optimal trajectories') for exciting 2 teeth simultaneously, spatial summation for pre-pain was demonstrated in most subjects and for pain in almost all subjects. Spatial summation of pre-pain resulted in pain rather than in more intense pre-pain. These results are consistent with both the dual modality (separate afferent fibers for pre-pain and pain) and the single modality hypotheses (single type of afferent fibers) of tooth pulp sensibility, but favor single modality innervation.

Adult↗
PubMed1982

Neuropharmacology of adrenergic neurons in teleost fish.

Although this brief review is based on relatively few types of experiments in few species of teleosts, it is possible to summarize some points of interest regarding the similarities and differences in the mechanisms of adrenergic neurotransmission in fish compared to the higher vertebrates. 1. There is a substantial mixing of cranial autonomic ("parasympathetic") and spinal autonomic ("sympathetic") pathways in the cranial nerves. This close relationship between the two systems and the differences in the nature of the neurons of cranial origin (cholinergic, and non-adrenergic, non-cholinergic) and spinal origin (adrenergic, cholinergic and mixed "polynergic") gives a basis in fish also for a complex pattern of innervation of the various organs. 2. Adrenaline is the major transmitter substance in the adrenergic neurons of most teleosts studied, but there are exceptions within the same species. For instance, in the swimbladder mucosa of the cod, noradrenaline dominates, while adrenaline is the major catecholamine in most other organs innervated by adrenergic neurons. The reasons for the regional differences are not known and further studies of the rate of catecholamine turn-over in the adrenergic neurons of fish are clearly indicated. 3. Adrenoceptors of both the alpha- and the beta-type show great similarities with those of mammals. Some differences in the potencies of certain compounds (e.g., clonidine and methoxamine) exist and receptor binding studies should add valuable information about the adrenoceptors of teleosts. The existence of a subtype of beta-adrenoceptor (beta 2) has been proposed and further work is needed to confirm or deny the applicability of the beta 1/beta 2 adrenoceptor terminology in fish. 4. There appears to be some differences in the mode of action of the so called "indirectly acting amines", such as tyramine, between teleosts and mammals. While the uptake of tyramine into the nerve terminals in mammals appears to take place via the cocaine-sensitive neuronal uptake system which is also responsible for catecholamine uptake (uptake 1), tyramine uptake in cod neurons appears to be via a separate pathway. 5. Presynaptic supersensitivity of the type seen in mammals has also been demonstrated in teleost adrenergic neurons. Both denervation (chemical or surgical) and blockade of the neuronal uptake mechanism by cocaine or desipramine produce this type of supersensitivity, while post-synaptic supersensitivity has so far not been described in teleosts. The effects of removal of the uptake system shows that the uptake process may be as important in teleosts as in mammals in the removal of adrenergic transmitter from the synaptic cleft. 6. In the total picture of adrenergic functions in fish, the circulating catecholamines take a special role...

Adrenergic Fibers↗
PubMed1994

Anatomical and physiological relationships between the anterior cerebellar vermis and the pontine parabrachial nucleus in the rabbit.

The anatomical connections between the midline cerebellum and the pontine parabrachial nucleus (PBN) were investigated in the rabbit using anterograde and retrograde axonal transport techniques. Small injections (20-50 nl) of cholera toxin conjugated to horseradish peroxidase (CT-HRP) or wheat germ agglutinin conjugated HRP (WGA-HRP) into the cortex of the anterior cerebellar vermis resulted in retrograde and anterograde-like label in the PBN. Focal injections of tracer into the PBN resulted in anterogradely labeled processes in the ACV and retrogradely labeled a small, but distinct group of Purkinje cells within the anterior vermis. Focal injections into the rostral fastigial nuclei (FN) resulted in anterograde-like label in the PBN, and PBN injections labeled FN neurons. Furthermore, the projection from the PBN to ACV is effective in driving cerebellar neurons as electrical microstimulation of the PBN evoked short-latency, phasic responses in ACV Purkinje cells. These experiments generated anatomical and physiological evidence for the existence of a neuroanatomical circuit connecting the midline cerebellum (ACV, FN) with the PBN, that may serve as a functional interface between the midline cerebellum and other brain stem nuclei with cardiovascular function, particularly with respect to the midline cerebellar role in classically conditioned cardiovascular responses.

Animals↗