Origins and neurochemical complexity of preganglionic neurons supplying the superior cervical ganglion in the domestic pig

TIGAR deficiency enhances skeletal muscle thermogenesis by increasing neuromuscular junction cholinergic signaling

Cholinergic and sympathetic counter-regulatory networks control numerous physiological functions, including learning/memory/cognition, stress responsiveness, blood pressure, heart rate, and energy balance. As neurons primarily utilize glucose as their primary metabolic energy source, we generated mice with increased glycolysis in cholinergic neurons by specific deletion of the fructose-2,6-phosphatase protein TIGAR. Steady-state and stable isotope flux analyses demonstrated increased rates of glycolysis, acetyl-CoA production, acetylcholine levels, and density of neuromuscular synaptic junction clusters with enhanced acetylcholine release. The increase in cholinergic signaling reduced blood pressure and heart rate with a remarkable resistance to cold-induced hypothermia. These data directly demonstrate that increased cholinergic signaling through the modulation of glycolysis has several metabolic benefits particularly to increase energy expenditure and heat production upon cold exposure.

Identification of neuropeptide y in superior cervical ganglion neurons that project to the oesophagus - A combined immunohistochemical labelling and retrograde tracing study in pigs

Neuropeptide Y (NPY) is a neuronal active substance taking part in the regulation of gastrointestinal (GI) tract activity. This study used retrograde neuronal tracing and immunofluorescence methods to analyse NPY-positive neurons located in superior cervical ganglion and supplying the cervical oesophagus in the pig. The presence of NPY was observed in 30% of all neurons supplying the part of oesophagus studied. Probably the number of Fast Blue (FB) positive cells depends on the area of the wall injected with FB and the fragment of oesophagus studied. Therefore, the obtained results indicate that the described peptide is an important factor in the extrinsic innervation of this part of the GI tract.

A study on preganglionic connections and possible viscerofugal projections from urinary bladder intramural ganglia to the caudal mesenteric ganglion in the pig

The present study was designed to (1) ascertain the distribution and immunohistochemical characteristics of sympathetic preganglionic neurons supplying the caudal mesenteric ganglion (CaMG) and (2) verify the existence of viscerofugal projections from the urinary bladder trigone intramural ganglia (UBT-IG) to the CaMG in female pigs (n = 6). Combined retrograde tracing and immunofluorescence methods were used. Injections of the neuronal tracer Fast Blue (FB) into the right CaMG revealed no retrogradely labelled (FB-positive; FB⁺ ) nerve cells in the intramural ganglia; however, many FB⁺ neurons were found in the spinal cord sympathetic nuclei. Double-labelling immunohistochemistry revealed that nearly all (99.4 ± 0.6%) retrogradely labelled neurons were cholinergic (choline acetyltransferase-positive; ChAT⁺ ) in nature. Many FB⁺ /ChAT⁺ perikarya stained positive for vesicular acetylcholine transporter (63.11 ± 5.34%), neuronal nitric oxide synthase (53.48 ± 9.62%) or cocaine- and amphetamine-regulated transcript peptide (41.13 ± 4.77%). A small number of the retrogradely labelled cells revealed immunoreactivity for calcitonin gene-related peptide (7.60 ± 1.34%) or pituitary adenylate cyclase-activating polypeptide (4.57 ± 1.43%). The present study provides the first detailed information on the arrangement and chemical features of preganglionic neurons projecting to the porcine CaMG and, importantly, strong evidence suggesting the absence of viscerofugal projections from the UBT-IG.

The production of nitric oxide in the coeliac ganglion modulates the effect of cholinergic neurotransmission on the rat ovary during the preovulatory period

The aim of the present work was to investigate whether the nitric oxide produced by the nitric oxide/nitric oxide synthase (NO/NOS) system present in the coeliac ganglion modulates the effects of cholinergic innervation on oxidative status, steroidogenesis and apoptotic mechanisms that take place in the rat ovary during the first proestrous. An ex vivo Coeliac Ganglion- Superior Ovarian Nerve- Ovary (CG-SON-O) system was used. Cholinergic stimulation of the CG was achieved by 10^-6 M Acetylcholine (Ach). Furthermore, 400 μM Aminoguanidine (AG) - an inhibitor of inducible-NOS was added in the CG compartment in absence and presence of Ach. It was found that Ach in the CG compartment promotes apoptosis in ovarian tissue, probably due to the oxidative stress generated. AG in the CG compartment decreases the release of NO and progesterone, and increases the release of estradiol from the ovary. The CG co-treatment with Ach and AG counteracts the effects of the ganglionic cholinergic agonist on ovarian oxidative stress, increases hormone production and decreases Fas mRNA expression. These results suggest that NO is an endogenous modulator of cholinergic neurotransmission in CG, with implication in ovarian steroidogenesis and the apoptotic mechanisms that take place in the ovary during the preovulatory period in rats.

Overview of the Anatomy, Physiology, and Pharmacology of the Autonomic Nervous System

Comprised of the sympathetic nervous system, parasympathetic nervous system, and enteric nervous system, the autonomic nervous system (ANS) provides the neural control of all parts of the body except for skeletal muscles. The ANS has the major responsibility to ensure that the physiological integrity of cells, tissues, and organs throughout the entire body is maintained (homeostasis) in the face of perturbations exerted by both the external and internal environments. Many commonly prescribed drugs, over-the-counter drugs, toxins, and toxicants function by altering transmission within the ANS. Autonomic dysfunction is a signature of many neurological diseases or disorders. Despite the physiological relevance of the ANS, most neuroscience textbooks offer very limited coverage of this portion of the nervous system. This review article provides both historical and current information about the anatomy, physiology, and pharmacology of the sympathetic and parasympathetic divisions of the ANS. The ultimate aim is for this article to be a valuable resource for those interested in learning the basics of these two components of the ANS and to appreciate its importance in both health and disease. Other resources should be consulted for a thorough understanding of the third division of the ANS, the enteric nervous system. © 2016 American Physiological Society. Compr Physiol 6:1239-1278, 2016.