Catecholamines in the sympathetic nervous system of the domestic fowl

The Role of Biogenic Amines in Nutrition Toxicology: Review

Biogenic amines, which are responsible for the realization of many physiological conditions of our body, are compounds that can be produced by microorganisms especially in fermented foods with high protein content. They can have harmful effects on human health only when taken in high amounts with food. However, in individuals with impaired anti-toxic metabolism, which is responsible for detoxification, even lower amounts may cause toxic effects. The most common health effects are nausea, vomiting, severe headaches, hypotension, hypertension, tachycardia, various allergic reactions, abdominal pain and death in more severe cases. For these reasons, legislations on biogenic amines in foods have been established with some restrictions. Food producers have been asked to comply with these legislations. However, despite all precautions, biogenic amines in foods have not been completely removed. Further research is still needed to find effective solutions to prevent biogenic amine formation. In addition, consumers need to be made aware of this issue.

Autonomic control of the urogenital tract

The urogenital tract houses many of the organs that play a major role in homeostasis, in particular those that control water and salt balance, and reproductive function. This review focuses on the anatomical and functional innervation of the kidneys, urinary ducts and bladders of the urinary system, and the gonads, gonadal ducts, and intromittent organs of the reproductive tract. The literature, especially in recent years, is overwhelmingly skewed toward the situation in mammals. Nevertheless, where specific neurochemical markers have been investigated, common patterns of innervation can be found in representatives from most vertebrate classes. Not surprisingly the vasculature, epithelia and smooth muscle of all urogenital organs receives adrenergic innervation. These nerves may contain non-adrenergic non-cholinergic (NANC) neurotransmitters such as ATP and NPY. Cholinergic nerves increase motility in most urogenital organs with the exception of the kidney. The major NANC nerves found to influence urogenital organs include those containing VIP/PACAP, galanin and neuronal nitric oxide synthase. These can be found associated with both smooth muscle and epithelia. The role these nerves play, and the circumstances where they are activated are for the most part unknown.

Social stress differentially regulates neuroendocrine responses in laying hens: I. Genetic basis of dopamine responses under three different social conditions

Effects of genetic-environmental interactions on plasma dopamine (DA) concentrations were studied in White Leghorn chickens selected for both high (HGPS) or low (LGPS) group productivity and survivability resulting from cannibalism and flightiness. Plasma DA levels were measured from chickens in three social treatments: single-, two-, or ten-hen cages. The two-hen treatment consisted of paired chickens from three genetic lines: HGPS, LGPS and a commercial strain, Dekalb XL (DXL). In HGPS/DXL and LGPS/DXL pairs, the DXL hen was used as a standardized genetic competitor. The ten-hen treatment contained only hens from the same line, which is similar to the original selection condition. After 7 weeks housing in the social environments, LGPS hens in the ten-hen treatment had greater plasma DA concentrations than HGPS hens (P<0.05). Compared to levels in the ten-hen treatment from the same line, plasma DA concentrations in both HGPS and LGPS hens were significantly lower in the two-hen treatment (average mean, 0.09 vs. 0.15 ng/ml and 0.22 vs. 0.44 ng/ml, P<0.05, respectively), but significantly higher in the single-hen treatment (average mean, 0.44 vs. 0.15 ng/ml and 1.78 vs. 0.44 ng/ml, P<0.05 and P<0.01, respectively). In the single-hen treatment, LGPS hens had greater plasma DA levels than HGPS hens (P<0.05). The results provide evidence of genetically related differences in the regulation of chickens' plasma DA concentrations in response to social stress. These differences may magnify the behavioral and physiological differences observed in the lines under basal and challenged conditions. These results suggest that these chicken lines may provide a new model for investigating effects of DA on the control of behavioral, neural and endocrine responses to stress.

In vivo neurotoxin administration alters immune responses in chickens (Gallus domesticus)

1. 6-Hydroxydopamine (6-OHDA) administered in ovo enhanced in primary immune response to sheep red blood cells (SRBC) in chicks 2. Splenic norepinephrine levels increased during the peak anti-SRBC response. 3. Cell-mediated immunity as measured by delayed-type hypersensitivity to phytohemagglutinin-P (PHA-P) was not affected by treatment with 6-OHDA.

Sympathetic innervation-mediating protein

The present study was performed to elucidate the mechanisms and molecular basis of specific innervation of the peripheral tissues. Chick sympathetic nerve fibers densely innervate expansor secundariorum muscle, but not skeletal muscle. When a sympathetic ganglion was cultured in collagen gel with muscle explants, the ganglion extended neurites towards two types of muscles to the same extent. Dissociated sympathetic ganglion neurons adhered firmly to the dish precoated with materials from expansor secundariorum but not to the dish precoated with those from skeletal muscle. Sympathetic nerve fibers were found densely distributed on the substrate from expansor secundariorum but not on the substrate from skeletal muscle. These results suggest that neuronal recognition mechanisms are involved in the process of selective sympathetic innervation of the expansor secundariorum muscle of the chick. The protein which caused the dense distribution of sympathetic fibers as the substrate has been purified from heart-cell-conditioned medium. The most purified fraction showed a single band with an apparent molecular weight of 370,000 daltons on SDS-PAGE under non-reducing and reducing conditions. The biological activity of the protein was over 100 times higher than that of laminin. Antiserum was raised against the factor in heart-cell-conditioned medium that induced the dense distribution of sympathetic fibers in culture. Addition of the antiserum to the culture medium inhibited the dense distribution of sympathetic fibers on the purified protein-substrate without affecting the general growth of the fibers. Subcutaneous injection of the antiserum into the chicks inhibited the regeneration of adrenergic fibers following 6-hydroxydopamine-induced axotomy in peripheral tissues (heart, spleen, kidney and blood vessel).(ABSTRACT TRUNCATED AT 250 WORDS)

Influence of corticosterone infusion on plasma levels of catecholamines, thyroid hormones, and certain metabolites in laying hens

Corticosterone was infused continuously through subcutaneously implanted mini-osmotic pumps into laying White Leghorn hens at the rate of 30 micrograms/hr for 14 or 28 days. In both groups receiving corticosterone, plasma levels of glucose and triglycerides were not altered significantly. Circulating levels of cholesterol and free fatty acids increased significantly following both 14 and 28-day infusions of the hormone. Corticosterone treatment for 28 days produced significant increases in plasma levels of thyroxine (T4) and triiodothyronine (T3). However, following the 14-day corticosterone infusion, only T3 showed significant increase. The T3:T4 ratio in both groups of corticosterone-infused hens was significantly higher than in control hens. The concentration of plasma epinephrine showed no significant response to corticosterone treatment, while norepinephrine increased significantly following both periods of treatment.

Effects of vagotomy on circulating levels of catecholamines and corticosterone in the pigeon

The effects of bilateral cervical vagotomy on the blood levels of corticosterone, and catecholamines, adrenaline (A) and noradrenaline (NA), in pigeons, were studied. Plasma levels of corticosterone and NA were found to be significantly higher and of A lower, in the vagotomized (VgX) pigeons as compared to their sham-operated (VgS) controls. These changes in VgX pigeons are explained as caused mainly by the lack of the vagal tone.

Effect of vagotomy on plasma levels of growth hormone, free fatty acids and glucose in the pigeon

Plasma levels of growth hormone (GH), free fatty acids (FFA) and glucose were measured in vagotomized (VgX) and sham-operated (VgS) control pigeons. In VgX pigeons, GH level was significantly lower whereas FFA and glucose levels were higher than in VgS pigeons. The depression in GH level in VgX pigeons has been attributed to the significantly high levels of norepinephrine (NE) and corticosterone in these Birds. The higher plasma FFA concentration in VgX pigeons was therefore due to adipokinetic hormonal action other than of GH. It has been suggested that the adrenocorticotrophic hormone (ACTH) and/or NE could have produced the increase in plasma FFA in VgX pigeons. The pronounced hyperglycemia seen in VgX pigeons has been attributed to catecholamine action in the absence of the vagal tone.

Characterization of chromaffin-like cells in the canine sympathetic chain by enzyme immunohistochemistry and quantitation of their distribution

Some of the paravertebral sympathetic ganglia of the dog contain relatively large amounts of dopamine, which we have suggested previously is localized in dopaminergic neurones. However, the possibility exists that intraganglionic chromaffin-like cells may also be a source of dopamine. In order to resolve this question, we have examined the distribution of chromaffin-like cells in dog paravertebral ganglia (T7-S2) using formaldehyde-induced fluorescence of catecholamines and immunohistochemical localization of dopa decarboxylase, dopamine beta-hydroxylase and phenylethanolamine N-methyltransferase. The results have been compared with levels of the different endogenous catecholamines in equivalent ganglia. Clusters of between 20 and several thousand chromaffin-like cells were randomly present in ganglia at all levels of the chain, and were most common in the more caudal segments (L4 or below); but many ganglia contained no cells. About 24,000 chromaffin-like cells were found in 18 ganglia from six animals which were stained for dopa decarboxylase and dopamine beta-hydroxylase. In 16 of these ganglia, all of the 17,000 cells present contained both enzymes, indicating that they could synthesize noradrenaline. In the remaining two ganglia, 500 out of 7000 cells contained dopa decarboxylase, and therefore were capable of synthesizing dopamine, but appeared to lack the dopamine beta-hydroxylase necessary to convert this to noradrenaline. Five ganglia from three other dogs were stained for dopamine beta-hydroxylase and phenylethanolamine N-methyltransferase. A further 2600 cells were found in these ganglia and both enzymes were present in all of the cells, indicating that they could all synthesize adrenaline. Biochemical estimates of the various catecholamines showed that ganglia containing appreciable amounts of adrenaline had similar distributions to those containing chromaffin-like cells in the same animals. High concentrations of adrenaline were often correlated with high concentrations of noradrenaline but were not correlated with high concentrations of dopamine. It is concluded that paravertebral chromaffin-like cells in the dog store adrenaline, and also perhaps noradrenaline, but not dopamine. The high concentrations of dopamine found in certain ganglia cannot therefore be attributed to the presence of these cells. The erratic distribution of chromaffin-like cells suggests that they are unlikely to fulfil any general role in modulation of ganglionic transmission.